Adherence to treatment guidelines for uncomplicated malaria at two public health facilities in Nigeria; Implications for the 'test and treat' policy of malaria case management
2014

Charles C Ezenduka firstname.lastname@example.com
Department of Clinical Pharmacy & Pharmacy Management
Faculty of Pharmaceutical Sciences
Nnamdi Azikiwe University Awka Agulu campus
AguluNigeria

Mathew J Okonta
Department of Clinical Pharmacy & Pharmacy Management
Faculty of Pharmaceutical Sciences
Nnamdi Azikiwe University Awka Agulu campus
AguluNigeria

Charles O Esimone
Department of Clinical Pharmacy & Pharmacy Management
Faculty of Pharmaceutical Sciences
Nnamdi Azikiwe University Awka Agulu campus
AguluNigeria

Adherence to treatment guidelines for uncomplicated malaria at two public health facilities in Nigeria; Implications for the 'test and treat' policy of malaria case management

Journal of Pharmaceutical Policy and Practice
7152014R E S E A R C H Open Access * Correspondence: Full list of author information is available at the end of the article Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Uncomplicated malariaTreatment guidelinesPolicy adherenceAntimalarial drugsPrescription practicesHealth facilityNigeria
Objectives: Adherence to treatment guidelines for uncomplicated malaria is critical to the success of malaria case management. Poor adherence has implications for increased malaria burden, in view of the risk of widespread parasite resistance and treatment failures. This study analyzed the diagnostic and prescription pattern for uncomplicated malaria at two public health facilities, south east Nigeria, to assess the current state of compliance to policy guidelines on the use of artemisinin-based combination therapy (ACT). Methods: Retrospective audit of patients' records, treated for uncomplicated malaria, between the months of January and March 2013, was undertaken at two public health facilities. Demographics, diagnostic information, medication and cost data were extracted. Questionnaires were distributed to providers to assess their malaria treatment intent. Data from the facilities were analyzed and compared for similarities and systematic differences, and conformity to malaria treatment policy, in terms of laboratory diagnosis, use of ACT, co-medication and cost of medication.Results: A total of 2,171 records of patients who had been treated for uncomplicated malaria were analyzed. Of these, 1066 (49%) were sent for laboratory confirmation of malaria using mostly microscopy, out of which 480 (45%) tested positive. 51% (1105) of the prescriptions was on the basis of presumptive treatment. 58% of slide negative results received antimalarial drugs. 93% of patients received ACT, with artemether-lumefantrin, AL (50.5%) as the most prescribed antimalarial drug. Monotherapy accounted for 7% of prescriptions, comprising mostly sulphadoxine + pyrimethamine, SP (46.5%) and monotherapy artemisinin, AS (29.2%). 97% of the prescriptions received at least one co-medication. Antibiotics were prescribed to 50% of patients. Overall, median cost of medication was N1160.00 ) per case, higher in tertiary than the secondary facility. There were significant variations in treatment practices between the two facilities.Conclusion: Evidence suggests good compliance to policy on the use of ACT as first line treatment for uncomplicated malaria. However, there exists significant scope for improved diagnosis and rational drug use, to enhance accuracy of treatment, reduced wastages and risks of adverse drug reactions, in line with the goals of 'test and treat' policy of malaria case management.

Introduction

Case management remains a major strategy for effective control of malaria, comprising diagnosis and prompt treatment with effective antimalarial drugs. In recognition of its high efficacy and potential for preventing development of parasite, ACT was recommended for the first line treatment for uncomplicated malaria in 2001 [1]. However, in view of the need to achieve efficiency in malaria treatment and enhance the goals of case management, the World Health Organisation (WHO) recommended the test, treat and track (TTT) policy, which emphasises improved diagnosis of malaria infection, prompt treatment with effective antimalarial drugs and regular monitoring through routine information system to ensure effective implementation [2,3]. Subsequently many malaria endemic countries in Africa adopted the policy, highlighting the importance of parasitological diagnosis using either microscopy or rapid diagnostic tests (RDTs) for malaria treatment, in all age groups and in all epidemiological settings [3,4]. This led to an increased supply of RDT. However, major challenge to implementation of policy guidelines has remained that change in policy recommendations does not always translate to immediate and effective change at health care provider levels and hence, inadequate quality case management at the point of care [5]. Consequently, inappropriate practices in the provision of malaria treatment have been reported among healthcare providers, from facilities in many malaria settings [5][6][7][8]. This constitutes non-adherence to treatment guidelines, contributing to undermining the goals of malaria treatment policy.

Adherence to policy guidelines by healthcare providers and patients is essential for achieving the success of this policy [3,9]. Studies in developing countries suggest that many years after the introduction of ACT, inappropriate prescription and use of antimalarial drugs persist, at both public and private health facilities [6][7][8][9]. With better exposure to information, it is expected that health workers in public facilities would have better access to malaria treatment guidelines, and be more likely to adhere to recommended strategy for uncomplicated malaria [7]. Although the public health facilities, more than the private sector, are known to largely conform to policy on the use of antimalarial drugs [10,11], reports indicate substantial inappropriate treatment practices, such as presumptive treatment, treatment of slide -negative results, co-medication (poly-pharmacy), use of low quality and expensive ACT and monotherapy [7][8][9]. These lead to wastages and inefficiency in the implementation of malaria case management, thereby increasing the risk of widespread resistance and treatment failures.

A study in Kenya [12] demonstrated how lack of adherence to treatment guidelines was associated with inappropriate prescription practices. The use of sub-therapeutic doses of drugs contributes to the risk of developing parasite resistance [13]. Drug regimens with long duration of treatment, such as monotherapy artesunate also contribute to poor adherence [8,14]. Concomitant medications further contribute to inappropriate prescription through polypharmacy, which increases risks of drug interactions, adverse drug reactions, non-adherence and treatment failures, in addition to high cost of care [11]. Presumptive treatment in health facilities have been shown to be widespread even with the availability of diagnostic instruments. Evidence also suggests frequent use of antimalarial drugs by health workers on slide-negative results [3,5,7,15]. Given the substantial misdiagnosis of febrile patients for malaria cases, using presumptive diagnosis, the use of antimalarial drugs under the current policy involving the use of more expensive ACT, represents substantial economic losses.

Several factors have been identified to be responsible for the non-adherence of prescribers to recommended guidelines. Inadequate supply of recommended drugs, unnecessary use of more expensive recommended drugs, continuous availability of monotherapy, staff shortages and high work load, as well as contradicting training messages that confuse workers [9,16], have been reported. These represent supply-side factors which limit effective implementation of malaria treatment policy. In Nigeria, although change in policy to the use of ACT was introduced in 2005 [17], inappropriate practices have been reported by many studies [7,10]. Understanding these issues is essential for generating information for implementing strategies to improve effective malaria treatment. This study was aimed to describe and assess the diagnostic and treatment patterns for uncomplicated malaria at two public health facilities in Nigeria, and determine current conformity to policy guidelines.

Methods

Study population

The study was undertaken in Anambra state, south-east Nigeria, with a total population of 4.18 million inhabitants by 2006 Nigerian census, considered as the second most densely populated state in the country (1,500 -2000 persons per km 2 ). Divided into three senatorial zones, the state has 21Local government Areas (LGAs). The people, who are predominantly ethnic Ibos, are involved in farming as the main occupation, while a significant number is into trading and commerce. Malaria transmission in the state is perennial with incidence rate of between 10 -35% and peak season coinciding with the rainy season, running between March and October every year. Children and pregnant women are the most affected by malaria. There are about 382 primary health centres (PHCs), managed by the LGAs, 32 secondary health facilities run by state government and two tertiary health facilities owned by the state and federal governments respectively. As in most of the Nigerian population, Plasmodium falciparum is the dominant malaria specie in the state, and artemetherlumefantrine (AL) is first-line drug for the treatment of uncomplicated malaria since 2005, followed by Artesunateamodiaquine (AA) as alternative first line drug. Presently, a wide range of ACT is registered in Nigeria for the first line treatment of uncomplicated malaria, such as dihydroartemisinin-piperaquine (DHAPQ) and artesunatemefloquine (ASMQ) [11]. The state is one of the most important sources of drugs supply in Africa, due to the presence of the popular 'Bridge-Head' market, a known center of drug trade, located in Onitsha, the largest commercial city in the state.

Study sites and setting

The study was carried out in two sites of a federal institution, the Nnamdi Azikiwe University (NAU). These include, NAU Medical Center (NAUMC) located at Awka, the state capital and NAU Teaching Hospital (NAUTH), Nnewi, the second largest commercial city in the state. The sites represent primary/secondary and tertiary healthcare facilities involved in malaria treatment, and were selected because of the opportunities they present for collecting quality and reliable data.

The NAU Medical Center is a healthcare facility which primarily provides outpatient services in a university community of about 50,000 people, as the catchment population. Significant number of the Awka community also accesses care at the facility. It has about 10 medical officers who provide clinical services to patients in addition to nurses, pharmacists, laboratory officers and other health workers. The center has a functional laboratory which provides microscopy and RDT services. There are 10 inpatient beds, which are used to provide brief admissions for emergency cases. Over 10,000 outpatient cases are treated annually at the facility. The supply of anti-malarial drugs is carried out through a process that is based on a procurement guideline. Donors also provide support through donations of drugs, such as the Affordable Medicine Facility-malaria (AMFm) drugs, though quantities of supply are relatively small. Availability of antimalarial drugs in the facility is said to be regular although, in many occasions there is a limited range of the products at any one point in time, due to purchasing procedures. Payments are made by all patients including staff, students and community members, who access services at the center. Payment by the students is deducted from fees paid in advance.

NAUTH is a 500-bed tertiary healthcare facility providing a variety of specialized clinical and teaching services. It is the main referral public health facility in the state run by the federal government. As at 2010, the hospital had total staff strength of about 2400 workers, spread across the various clinical and non-clinical departments; comprising over 300 doctors, 400 nurses and 62 pharmacists, including intern pharmacists. There are 15 wards with estimated 80% bed occupancy. The general outpatient department (GOPD) attends to over 12,000 outpatient visits annually. Patients pay for services and their drugs at the point of delivery.

Study design and data collection

A descriptive cross-sectional study was conducted, based on retrospective cohort event monitoring of patients treated for uncomplicated malaria in the course of medical practice. Facilities were selected to ensure availability of adequate patient load and coverage, and the need to recruit large enough patients in a short period. Hospital records of patients diagnosed or treated for uncomplicated malaria, within a three month period of between January and June 2013, were collected and audited. Cases of severe/complicated malaria and pregnant women were excluded. Two pharmacy graduates were trained to extract and record the data from the patients' records into a predesigned Excel data form. Individual patient-level records and prescription were collected for each outpatient treated at the facilities. Collected data included demographics, diagnosis, laboratory tests results, drugs prescribed, number of drugs, cost of drug prescription and co-prescribed medications, over the study period. Medication doses and route of administration were not documented, but the drugs were prescribed and dispensed in age-related doses. Pre-tested semi-structured questionnaires of 15 questions were distributed to the prescribing physicians in selected facilities, to assess their prescribing intent in the treatment of uncomplicated malaria, in terms of the use of laboratory services, antimalarial drug-use and prescription pattern.

Data management and analysis

Data was double entered, cleaned and managed with Excel spreadsheet. Analysis was carried out for diagnostic approaches, (use of microscopy and/or RDT), use of ACT, monotherapy, concomitant medication and cost of medication. Prescriptions were categorised into ACT and mono therapy. Analysis was carried out at whole facility level (facilities are located in the same state) and then separately for individual facility, to assess the differences in treatment pattern between the facilities in conforming to malaria treatment guidelines. Conformity to treatment guidelines was on the basis of laboratory diagnosis, use of ACT and rational use of drugs.

Data were collected using Excel spreadsheet and statistical analysis was performed using SPSS version 16 (SPSS Inc., Chicago, IL, USA) and GraphPad Prism 5 for Windows, (GraphPad Software, San Diego California USA). Association between variables of interest and the prescription of antimalarial drugs were estimated using logistic regression. Chi squared test of independence was used to determine association between categorical variables, independent student's t-test for continuous variables, and univariate analysis to predict the prescription of ACT and concomitant medications. Statistical significance was set at p = 0.05.

Ethical considerations

The study obtained approval from the NAUTH Ethical Committee as part of a larger study on the pharmacoeconomics of malaria treatment in Nigeria. Each doctor's consent was obtained to participate in the questionnaire survey. The study did not involve direct patient contact hence patient consent was not necessary.

Results

Study characteristics and malaria diagnosis

A total of 7949 outpatient visits were identified, out of which 2171(27.3%) cases were treated for uncomplicated malaria. Ninety-four (4%) records were excluded due to either severe malaria or incomplete/missing information on variables of interest. 49% (1066) of those treated for malaria was sent for laboratory examination while the rest, 51% (1105) was based on presumptive diagnosis. 48% of laboratory diagnosis tested slide positive while 52% tested negative. Only the tertiary health facility reported the use of RDT. Figure 1 shows the graphic presentation of selection process. The proportion of uncomplicated malaria cases was higher at the medical center, 47% (1261/2674) compared to the teaching hospital, 17% (910/5252).

Characteristics of cases finally analyzed (Table 1) shows that overall, females (56%) outnumbered males (43%). Gender disparity was higher at the teaching hospital than the medical center where females, 65% outnumbered males, 35%, (p <0.0001). Most cases (62%) fall between 19 years and above, at a median age of 23 years, ranging from one month to 98 years. Children under 5 years accounted for 10% of total cases. The proportion of children under five years was higher at the teaching hospital, 20% (181/910) compared to the medical center, 2.6% (33/1261). The proportion of ACT prescribed at the medical center (95%) was significantly higher than the teaching hospital, (91%, p < 0.003). Table 2 shows the distribution of antimalarial drugs (including co-medication) prescribed by facility. A total of 2,171 drug encounters were analyzed. Of these, 93% (2027) contained an ACT, while 7% (144/2171) was prescribed monotherapy. There were some variations in prescription pattern between the facilities. The proportion of patients who received ACT compared to monotherapy at the medical center, 95% (1198/1262) was significantly higher than the proportion prescribed at the teaching hospital at 91% (828/910, p = 0.003). Overall, the pattern of prescription shows that AL, at 51% (1024/2027) was the most prescribed ACT at both health facilities, followed by DHAPQ, 17% (339/2027) and ASAQ 12%. While this pattern was similar at the medical center, it differed from the teaching hospital where artesunate-   (7) 63 (5) 81 (9) --**= significant: ***= very significant: ****= highly significant. mefloquine (ASMF) and artesunate-sulphadoxine + pyrimethamine (ASSP) were the second and third most prescribed ACT respectively, after AL. Highest proportion of monotherapy was prescribed as SP, 47% (67/144), followed by artesunate monotherapy (AS), 29.2%. The pattern, however reversed at the teaching hospital where AS, 43% (35/81) was the most prescribed monotherapy, followed by SP, 22% (18/81). More monotherapy (9%) was prescribed at the teaching hospital compared to the medical center (5%). Prescription pattern also varied by age and gender. Higher proportion of SP, 49% compared to other monotherapy agents was prescribed to females than males, 44%. Similarly more females, 29% received monotherapy AS than males, 27%.

Antimalarial drugs prescription pattern

Co-prescribed medication

97% of the patients received at least one co-prescribed medication, at an average of 4 (±1.5) drugs per prescription. Analgesics were the most commonly prescribed co-medication given to 79% (1722/2171) of the cohort, followed by vitamin preparations (63%), and antibiotics (50%). The pattern varied significantly between the facilities and across categories (Tables 2 and 3). Proportion of coprescribed medications was higher at the medical center, 99% compared to the teaching hospital, (95%, p < 0.0001) ( Table 2). This was similar for the most commonly co-prescribed medications at the facilities. Majority, 57% of children under 5 years were more likely to be prescribed antibiotics compared to children between 5 and 12 years (37%, p <0.001) and adults, (53%; p < 0.05) ( Table 3).

Prescription pattern in children under 5 years

Of the 214 under 5-year old children in this study, 85% (182) received ACT. AL, 70% (128/182) was the most preferred antimalarial drug of choice, followed by artesunateamodiaquine (ASAQ), 16%. The use of monotherapy occurred most in this group compared to other age categories, and amodiaquine, 38% (12/32) was the most commonly prescribed monotherapy, followed by monotherapy artesunate (AS), 34%. Majority, 57% of the under-5 year old children were more likely to be co-prescribed antibiotics than children between 5 and 12 years (37%, p <0.001) and adults, (53%; p < 0.05) ( Table 3). In many cases, the antibiotics were prescribed in combination with cough medications. Co-prescription with analgesics and vitamin preparations was also common in children. Table 4 shows that overall, the median cost of medication (including co-medication) per patient at the two facilities was N1160 (US$7.48) . Medication cost of treatment per patient at the tertiary hospital, N1378 (US$8.89) is about 27% higher than at medical center N1083 (US$6.99). Between the groups, median cost of medication was lowest in children 5 -12 years, N776 (US$5.01), compared to adults 19 years and above, N1160 (US$7.83). The cost of treatment with ACT, N1176 (US$7.59) is about 1.6 times higher than the median cost of treatment with monotherapy, N750 (US$4.84). It was not possible separating the cost of malaria component of treatment from that of co-morbidity due to inadequate documentation on diagnosis. Hence, medication cost includes the cost of comorbidity. Questionnaire distribution recorded 100% response. While every respondent would often request for laboratory test for malaria before treatment, they would also sometimes treat by clinical diagnosis alone. Some of the reasons given for presumptive diagnosis include, confidence in their ability to diagnose malaria without laboratory test (100%), severity of symptom (80%), patient load and lack of waiting time (60%), and previous experience with particular symptom/s (60%). All prescribers (100%) would sometimes prescribe antimalarial drugs in slidenegative results for a variety of reasons; need to prevent malaria infection (40%), unreliable result (60%), and unaware of result (40%). All respondents were aware of availability of malaria treatment guidelines and all would use AL as the preferred ACT of choice for its efficacy and minimum side effects. All doctors use ACT based on recommended guidelines.

Costs of medication

Discussion

This study illustrates practical realities in the treatment of uncomplicated malaria in public health facilities in Nigeria, which has implications for the implementation of malaria treatment guidelines. Findings reflect practices as they relate to the test and treat policy of malaria control. The predominance of the female gender is consistent with many studies [7,8,18,19], where females outnumbered males in health facilities compared to the retail sector. This observation agrees with the suggestion that females make more use of public health facilities than males, who tend to prefer medicine outlets [11]. The finding also implies that women suffer more from malaria attack than males in the study area. The higher proportion of malaria cases at the medical center, (a primary/secondary health facility) is easily explained by the fact that primary health facilities are the main sources of treatment for uncomplicated malaria [9]. The 27% malaria incidence in this study would suggest a declining incidence compared to previous reports of 60% incidence for outpatients consultations in Nigeria [20].

The use of laboratory diagnosis for malaria treatment in the two facilities was limited to 49%, relying substantially on presumptive diagnosis, contrary to the test and treat recommendations of current guidelines. This indicates high incidence of over-diagnosis and over-use of antimalarial drugs, in view of the degree of inaccuracy associated with presumptive malaria treatment [15,21,22]. The finding corroborates previous studies in Nigeria and other African countries which have reported widespread limited use of laboratory diagnosis in malaria treatment, even with the presence of diagnostic tools [3,8,15,21]. It reflects the level of confidence and popularity to which prescribers attach to presumptive malaria treatment, as was confirmed by doctors' responses. This is consistent with findings by Onwujekwe et al. in 2009 andUzochukwu et al., in 2010, in which over 80% of providers at both hospital and nonhospital alike, are confident in clinical diagnosis of malaria [10,21]. The study by Meremikwu et al. in 2007, reported laboratory test rate of 45% [8], while Uzochukwu et al. reported a rate of 51.1% in Enugu [21], suggesting no significant improvement since 2010. The level of confidence in clinical diagnosis should be considered unrealistic in view of the evidence to the contrary and the high incidence of inaccuracy and wastages associated with presumptive malaria treatment [22]. Consequences include missed diagnosis of other illnesses and increased risk of morbidity [23]. This underscores the need for intensified efforts at promoting the use of diagnostic approach to malaria treatment at the facilities, through regular education programmes for health workers [3]. In addition, findings also suggest that low utilisation of diagnostic test was due to high patient load and hence, lack of waiting time for receiving the result of the test, which should be noted for improvement. The benefit of RDT in terms of rapid delivery of results addresses this problem. Patients were treated presumptively even with the availability of laboratory tools in the facilities. The proportion of patients who received antimalarial drugs with slide negative results was quite substantial, considering the enormous wastages that accompany this. This was justified by the prescribers for a number of reasons; (1) unreliability of laboratory results due to poor laboratory reagents, (2) RDT insensitivity (further studies may be required to explore this), and 3) unaware of laboratory results. Previous studies in the area have similarly reported unreliability of laboratory results as a major cause of treatment of slide negative results, especially with RDT [10,21]. Hence, the study showed limited use of RDT compared to microscopy, even when it was available in both facilities, confirming the lack of trust of providers on RDT test results. This should worry policy considering the international focus on the use of RDT and implication for the goal of TTT policy [2,3]. Further investigation on the supply of quality RDT products for intervention is required, to ensure reliability of its results and the success of the test and treat policy. There is clear need for improved laboratory standards for malaria diagnosis, which can be achieved through a simple system of quality control. Continuous education of providers through regular seminars and workshops, on the benefits of confirmatory diagnosis cannot be over-emphasized. The extent of treatment of slide negative results and doctors responses to the issue calls for strategies to enhance their respect for negative results. There is need to enforce quality control to enhance reliability of diagnostic results. Benefits of confirmatory diagnosis and consequences of poor laboratory practices should be part of the regular updates to boost the confidence of prescribers in adhering to laboratory diagnosis. Pattern of prescription in the study shows a clear preference for ACT, as the drug of choice for uncomplicated malaria at the two health facilities. This indicates high conformity to policy recommendation. The preference for AL, the policy first line drug at both facilities indicates providers' confidence in the efficiency of the regimen, as was confirmed by questionnaire responses. The pattern appears similar to what obtained in the retail sector in the area, where DHAPQ was also found to be the second most prescribed antimalarial drug/ACT [11]. However, the greater dominance of ACT in this study, 95% compared to the retail sector 73%, is consistent with findings that public health facilities conform more to policy guidelines than the retail sector [11]. The retail sector is dominated by self-medication, which is characterised by high incidence of monotherapy use. The fact that the medical center uses more ACT than the tertiary health facility can be explained by the predominance of children and female cases at the later in which monotherapy was most prescribed for prophylaxis. Preference for AL is consistent with many study findings in both Nigeria and other African countries [3,11,18]. Similar to the retail sector [11], the use of AA which was the policy's alternative policy drug, was limited in this study. This was also explained by the reported safety concerns associated with the use of AA, especially in adults known to present with varying degrees of side effects [11]. The prescription of SP, mostly for prophylaxis in the study conforms to guidelines for its use in Intermittent Preventive Treatment in pregnancy and children (IPTp and IPTc). However, the use of AS and quinine is not in line with policy and therefore should be of concern.

The use of an average of four drugs per prescription in this study suggests high incidence of co-medication, going by the WHO recommendation of two to three drugs for developing countries. This gives an indication of poly-pharmacy in the studied facilities, increasing the risks of drug interactions, adverse drug reactions and high cost of treatment for the patients. Co-medication was higher at the medical center with five drugs per prescription. While poly-pharmacy may be justified in some cases by the significant number of co-morbidity, proportion of co-medication with vitamin preparations and antibiotics has implications for the safety and efficacy of antimalarial drugs. The fact that many of the prescriptions were on the basis of presumptive diagnosis, made this situation more critical, contributing to further wastages. There are concerns with co-administration of vitamin preparations with ACT in view of the antioxidant effects of vitamin compounds such as zinc, iron, vitamins C and E, on artemisinin compounds [24,25]. This may lead to reduced availability and hence reduced efficacy of the agents, and in consequence, contribute to treatment failures and increasing resistance of the Plasmodium. It has been advised that if needed, vitamins preparations could be used after completing the ACT dose. The use of antibiotics in absence of co-morbidity also has implications for safety, in view of their known side effects, which may be wrongly attributed to the antimalarial drugs. Coprescription with antibiotics occurs usually as 'a cover' for potential co-infection which would suggest that the prescriber is less confident of actual diagnosis, or prevent subclinical infection becoming manifest [26]. Hence, many prescriptions were secondary to diagnosed infections. Similar findings were reported from a study in Tanzania, for patients with a history of cough in the last 48 hours, for which antimalarials were prescribed even with negative results [15].

Although this study did not assess the appropriateness of antibiotics use, the likelihood of overtreatment with antibiotics, similarly reported in many other studies [26,27] had led to the call for better diagnostic approach to nonmalarial fevers and development of guidelines for management of such illnesses, which should be incorporated into malaria case-management trainings for health workers [3]. This recommendation should be treated as priority to enhance the rational use of both antimalarial drugs and antibiotics.

The total cost of medication per prescription (including co-medication) in this study, which showed a median of US$7.48, is about 2.6 times higher than similar cost obtained for retail outlets, (US$2.90) in a study undertaken at about the same period in a neighbouring city [11]. This is consistent with reported higher cost of care in public health facilities, due to the cost of more professional services [9]. This relatively higher cost of medication in public health facilities has remained as one of the major factors that inform the preference for the retail sector by a significant proportion of patients' population for malaria treatment [9]. The higher cost of medication at the tertiary health facility may be explained by the higher cost of expert care at a tertiary/referral center.

Treatment practices varied notably between the two facilities, in terms of patients' characteristics. The pvalue shows significance in many of the variables, indicating differences in prescribing practices of doctors between the facilities. These differences highlight the variation in prescribing cultures between similar facilities across the country, suggesting differences in dissemination of anti-malaria training information. The differences may also point to the levels of exposure to malaria treatment practices. Regular updates therefore provide opportunity for promoting appropriate malaria treatment practices in these health facilities [18]. Indicators suggest better performances at the teaching hospital compared to the medical center, which is consistent with reports that prescribers in tertiary institutions tend to adhere more to national treatment guidelines [28]. The presence of more specialized doctors at the tertiary center, who are probably better exposed to information than those at the medical center, may explain this.

Limitations

A few limitations are reported in this study. The selected sample facilities may reflect a potential bias towards public health facilities with high patient load. However, considering the health-seeking pattern for malaria treatment in Nigeria, where majority of cases are treated in the public sector compared to the private sector [29], selected facilities may be a likely representative of study population. Comprehensive diagnostic information was not collected due to inadequate documentation of patient diagnosis, to better inform the use of antibiotics and other concomitant medications. The study did not assess the appropriateness of prescription dosages and weights. However, most of the ACTs were administered according to age-related dose packages and hence most likely to conform to patients' ages and weights. While the study may be limited in scope in terms of the number of facilities studied, findings reflect, to a greater extent the practice pattern in the sector, considering the similarity in many ways, of the findings of previous studies carried out in the area [7,8,10,21] and other settings [26]. However, the study needs to be scaled-up to strengthen the findings for enhanced policy interventions for improved malaria case management.

Conclusion

Eight years after the change in antimalarial treatment policy, there is substantial compliance to policy on the use of ACT, as the first line treatment for uncomplicated malaria at the two health facilities. However, treatment practices are substantially characterised by limited use of laboratory diagnosis, relying mostly on presumptive treatment, over-diagnosis, over-treatment, co-medication and lack of routine information on malaria treatment, to guide effective implementation of treatment guidelines. These create the risk of developing parasite resistance and treatment failures, undermining the goals of malaria treatment policy. There is therefore a wide scope for improved diagnostic and treatment practices at the two health facilities, to enhance the efficiency of malaria case management. Targeted intervention through promotion and regular education of providers on appropriate malaria treatment practices is imperative, based on recommended guidelines and the test and treat policy. This would surely improve confirmatory diagnosis and rational drug prescribing, to achieve the goals of malaria case management. There is also the need to ensure adequate supply of quality and sensitive diagnostic equipments, which is critical to the success of the 'test and treat' policy of malaria case management.

Figure 1
1Schematic summary of selected malaria cases included in the study.

Table 1
1Characteristics of study population by facilityVariable
Total facility
n (%)

NAUMC Awka
n (%)

NAUTH Nnewi
n (%)

Chi square difference
p-value

Total number of outpatients visits
7926
2674
5252
-
-

Proportion of malaria cases
2171 (27)
1261 (47)
910 (17)
729.8
0.0001***

Mode of diagnosis

Microscopy
939 (43)
650 (52)
288 (32)
9.95
0.0016**

RDT
128 (6)
-
128 (14)
-
-

Presumptive
1105 (51)
611 (48)
494 (54)
0.875
0.3497

Gender

Female
1207 (56)
635 (50.4)
573 (63.0)
42.09
0.0001***

Male
942 (43)
626 (49.6)
316 (34.7)
-
-

Unknown
22 (1.0)
-
21 (2.3)
-
-

Age category (yrs)
20.29
0.0001***

Under 5
214 (10)
33 (2.6)
181 (20)
-
-

5 -12
52 (2)
22 (1.7)
30 (3)
-
-

13 -18
104 (5)
78 (6.2)
36 (3)
-
-

19 and above
1354 (62)
1026 (81.4)
330 (36)
-
-

Unknown
447 (21)
102 (8.0)
343 (38)
-
-

Median age of cohort (range)
23 (0.1 -98)
23 (1 -82)
24 (0.1 -98)

Antimalarial drugs

ACT
2027 (93)
1198 (95)
828 (91)
13.02
0.0003***

Monotherapy
144

Table 2
2Distribution of antimalarial drugs and co-medication prescribed by facilityAntimalarial drugs
Total facility
n (%)

NAUMC Awka
n (%)

NAUTH Nnewi
n (%)

Chi square difference
P = value

Artemisinin-based combinations (ACTs)
2027 (93)
1198 (95)
829 (91)
13.02
0.0003***

Artemether-lumefantrin
1024 (50.5)
647 (54)
377 (45.5)
-
-

Artesunate-amodiaquine
244 (12)
206 (17.2)
38 (4.5)
-
-

Artesunate-mefloquine
232 (11.5)
-
232 (28)
-
-

Artesunate-pyridoxine + pyrimethamine
188 (9.3)
56 (4.7)
132 (16)
-
-

Dihydroartemisinin-piperaquine
339 (16.7)
289 (24.1)
50 (6)
-
-

Mono-therapy
144 (7)
63 (5)
81 (9)
13.02
0.0003***

Artesunate
42 (29.2)
7 (11.1)
35 (43.2)
-
-

Amodiaquine
14 (9.7)
-
14 (17.3)
-
-

Proguanil
15 (10.4)
1 (1.6)
14 (17.3)
-
-

Quinine
6 (4.2)
6 (9.5)
-
-
-

Sulphadoxine + pyrimethamine
67 (46.5)
49 (77.8)
18 (22.2)
-
-

Proportion of co-medication n (%)
1722 (97)
1248 (99)
864 (95)
32.37
0.0001***

Analgesics
1722 (79)
1124 (89)
598 (66)
176.8
0.0001***

Vitamin preparations
1364 (63)
993 (79)
371 (41)
324.8
0.0001***

Antibiotics
1084 (50)
721 (57)
363 (40)
63.18
0.0001***

***= very significant.

Table 3
3Utilisation of antimalarial drugs across demographic categories NAUMC = Nnamdi Azikiwe University Medical Center, NAUTH = Nnamdi Azikiwe University Teaching Hospital.Gender
Age category (years)

Table 4
4Medication cost of treatmentTreatment cost (Naira)

Variable
Median
Range
Mean
95% CI

Antimalarial drugs

ACT
1176
45 -41520
1587
1511 -1663

Mono-therapy
750
30 -8485
1158
927 -1389

Gender

Male
1158
72 -41520
1340
1220 -1460

Female
1110
30 -16010
1499
1403 -1594

Age group

Under 5
1062
45 -7760
1151
1024 -1277

5 -12 yrs
776
30 -3734
914
741-1087.2

13 -18
1118
150 -7900
1243
1067 -1418

19 and above
1160
85 41520
1503
1412 -2595

Facility
1160
30 -41520
1559
1486 -1632

NAUMC
1085
85 -8000
1171
1135 -1207

NAUTH
1378
30 -41520
2101
1940 -2262

http://www.joppp.org/content/7/1/15
AcknowledgementAuthors appreciate the support of various heads and staff of relevant departments in the study facilities, for their kind support in providing all necessary documents for the study, ensuring successful collection of data from their respective facilities. The support of pupil and student pharmacists Nwabugo and Jeniffer in data collection and documentation is well acknowledged and appreciated.Competing interestsThe authors declare that they have no competing interests.Authors' contributions CCE conceived and designed the study, collected and analyzed data, wrote the manuscript. MO and COE assisted in study design, data interpretation and manuscript review. All authors read and approved final manuscript.
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Submit your next manuscript to BioMed Central and take full advantage of: • Convenient online submission • Thorough peer review • No space constraints or color figure charges • Immediate publication on acceptance • Inclusion in PubMed, CAS, Scopus and Google Scholar • Research which is freely available for redistribution. Journal of Pharmaceutical Policy and Practice. 715Submit your manuscript at www.biomedcentral.com/submitImplications for the 'test and treat' policy of malaria case management. Journal of Pharmaceutical Policy and Practice 2014 7:15. Submit your next manuscript to BioMed Central and take full advantage of: • Convenient online submission • Thorough peer review • No space constraints or color figure charges • Immediate publication on acceptance • Inclusion in PubMed, CAS, Scopus and Google Scholar • Research which is freely available for redistribution Submit your manuscript at www.biomedcentral.com/submit


Cubicle Refusal and Rearing Accommodation as Possible Mastitis Risk Factors in Cubicle-Housed Dairy Heifers
2001. 2001

H P Kjaestad
The Norwegian School of Veterinary Science
Department of Large Animal Clinical Sciences
OsloNorway

E Simensen
The Norwegian School of Veterinary Science
Department of Large Animal Clinical Sciences
OsloNorway

Cubicle Refusal and Rearing Accommodation as Possible Mastitis Risk Factors in Cubicle-Housed Dairy Heifers

Acta vet. scand
4212001. 2001
Kjaestad HP, Simensen E: Cubicle refusal and rearing accommodation as possible mastitis risk factors in cubicle-housed dairy heifers. Acta vet. scand. 2001, 42, 123-130. -Fifty-nine of the 65 dairy farms with cubicle sheds in the Norwegian county of Oppland in 1990 were included in a study of rearing accommodation, cubicle refusal and mastitis incidence. The farmers recorded the favoured resting location of the individual cows and heifers throughout the final week of pregnancy as well as during calving. The observations were matched with individual records of mastitis cases during the first 30 days after calving. Mastitis incidence in the heifers was analysed by logistic regression using rearing accommodation and cubicle refusal as independent variables, controlling for herd as a clustering factor. Cubicle refusal was found in 29% of the heifers, but in only 3% of older cows. The results of the analysis indicated a tendency for cubicle refusal to be associated with an increased mastitis incidence among the heifers (OR=2.2, c.i. 95%OR =0.9-5.4, P=0.08). Cubicle refusal accounted for 21% (0-32%) of the mastitis cases in the study population (PAF=0.21). dairy cows; cubicle housing; cubicle refusal; mastitis.

Introduction

Cubicle housing systems for dairy cows have a number of advantages over a tie barn, such as better reproduction and health among the cows (Ekesbo 1966, Bakken et al. 1988, Østerås 1990, Valde et al. 1997, good opportunities for them to exhibit different types of behaviour, and improved working conditions for the herdsman. Increasing attention to these factors has contributed to the building of many cubicle houses also in countries with small dairy farms, such as Norway. In a study of 186 out of 273 dairy farms with cubicle housing in Norway in 1990, the median herd size was found to be 18 cows (range 7-118) (Kjaestad & Myren 2001). The cows' use of the cubicles obviously depends on an initiative by the individual animal, and it may be influenced by factors such as cubicle-cow ratio (Kaiser 1974, Friend et al. 1977, Wierenga & Hopster 1990, cubicle design (McFarland & Gamroth 1994, O'Connell et al. 1991, and the softness of the cubicle surface (e.g. Jensen et al. 1988, O'Connell et al. 1993. Results from a previous study of Norwegian dairy herds showed that 6% of the cows in cubicle sheds refused to use the cubicles for resting, a behaviour hereafter referred to as cubicle refusal. However, the refusal percentage varied considerably between herds, and in some herds, more than 50% of the animals refused to use the cubicles (Kjaestad & Myren 2001). Cubicle refusal leads to soiling of the cow's udder and belly with urine and faeces, and contamination of the udder with a number of potentially pathogenic faecal bacteria, for instance Escherichia coli. In addition to increasing the load of pathogenic bacteria on the udder, lying on the dirty slatted floor makes the udder wet, and evaporation, as well as contact with the cool floor and draft between the slats, leads to local chilling, which may result in decreased local resistance (Dyrendal & Ewbank 1968). It is known that the incidence of E. coli-associated mastitis is higher in wet and dirty dairy barns than in dry and clean ones (Bartlett et al. 1992). We therefore suggest that animals which choose to lie in the alley are at a higher risk of developing mastitis than cows which choose to rest in cubicles. It is also probable that persistent cubicle refusal leads to premature culling of an animal because it increases the labour associated with cleaning the udders before milking. An association has previously been found between rearing heifers in slatted floor pens and the occurrence of cubicle refusal in the dairy herd (Kjaestad & Myren 2001), but the rearing environment may of course influence udder health by other factors than predisposing heifers towards cubicle refusal. Studies of tie-stall herds suggest that rearing heifers in group pens is associated with an increased mastitis incidence (Pettersen 1981(Pettersen , Østerås et al.1994 The present work was undertaken to study the incidence of cubicle refusal by heifers and cows, and to study the relationship between rearing accommodation, cubicle refusal and the incidence of clinical mastitis.

Materials and methods

All farms in Oppland county with cubicle sheds in 1990 were identified with the help of regional agricultural authorities, other farmers, and practising veterinarians. The farmers were contacted and asked to participate in the study. Sixty-five farms with cubicle sheds were identified and the farmers contacted. Five herds were entirely excluded from the study, three because the farmers did not want to participate in the study, and the other 2 because of lack of data recording and stocking twice as many cows as the number of available cubicles, respectively. All the herds included were visited before the calving season started, the cowhouses inspected, and notes made of whether the heifer rearing facilities were slatted floor pens or other types of accommodation. During the visit, the farmers were instructed to record data for individual cases on specially designed forms. The information requested was:

-Calving date and calving number -favoured resting site of the cow or heifer during the week before calving (cubicle, alley, halfway inside cubicle, combinations, or unknown) -site of calving (cubicle, alley, other, or unknown) -rearing accommodation of heifer (slatted pen or other accommodation -also confirmed by farm visit).

One form containing the requested information was to be completed for each calving that took place. All farmers were contacted by telephone one to two months after the calving season had started. The data were collected by the end of the calving season and reviewed in collaboration with the farmer. The cases of mastitis in the herds were diagnosed and recorded by the local practising veterinarians. The general definition of mastitis used was "clinical mastitis with signs of chronic or acute inflammation" (The Royal Ministry of Agriculture 1988). The individual disease records or "health cards" were kept on the farm, and the data regularly transferred to a central computer data base according to the practice of the Norwegian Herd Recording System (NHRS), an extensive recording system for health and production data (Solbu 1983). For each animal, the corresponding data on the occurrence of clinical mastitis were matched with the data on cubicle use recorded by the farmers.

Data on a total of 1125 calvings in the 60 herds were collected. Median herd size was 18 cowyears (range 11-109), and the median number of forms returned from each herd was 17 (range 7-54 ). Most of the calvings took place from primo July throughout October, 1990.

Of the 1125 animals in the study, 36% were first-calving heifers, 25% were cows giving birth to their second calf, and the remainder were cows at their third calving or later. About 10% calved while out on pasture, while 78% of the remaining calvings took place in the cubicle-equipped section. Thirteen percent calved in a calving pen, the remaining animals were tethered at the time of calving. The rearing environment of 387 of the 404 heifers was known. Of these, 86% had been reared in slatted floor pens, while the remaining 14% had been reared in various other facilities, mainly involving individual tethering.

Statistics

The incidence of mastitis during the first 30 days after calving (abbreviated MAST) was analysed by logistic regression for distinguishable data with herd as a random effects variable (Statistics and Epidemiology Research Corporation 1991). One herd was excluded from the analyses of mastitis incidence because it was not a member of the NHRS, reducing the population at risk to 1116 animals in 59 herds.

Only the first calving heifers were subjected to analysis because of low total occurrence of cubicle refusal in the older cows as well as the fact that variation in age made that group very heterogeneous. The other variables used in the analyses were:

-Cubicle refusal throughout the final week of pregnancy (CUBREF), "1" denoting cubicle refusal, "0" denoting cubicle use -rearing accommodation (SLATS ), "1" denoting slatted pen, "0" other accommodation.

Rearing in slatted floor pens has previously been linked with cubicle refusal (Kjaestad & Myren 2001). Therefore, it would not have been appropriate to include both SLATS and CU-BREF in the same model. Instead the 2 independent variables were analysed one at a time using the models:

MAST = a + bSLATS MAST = a + bCUBREF a being the regression constant (general mean), and b the regression coefficient of the independent variable. Each of the models was also tested with the addition of an interaction term  consisting of the product of the independent variables (SLATS × CUBREF). The population attributable fraction (PAF) for the risk factors was determined using the calculated OR values in the following formula, described by Bruzzi et al. (1985):
PAF = 1 -∑(p(D i |D+)/OR i )

Results

Data on cubicle refusal and calving number were reported for 1045 cows and heifers. Cubicle refusal throughout the final week of pregnancy, either intermittent or constant, was shown by 12%. This pattern of behaviour was more frequently seen in heifers than in first lactation cows or older cows (Table 1). The total incidence rate of mastitis during the first 30 days after calving was 8.7%. Mastitis was reported in 6.8% of the first-calf heifers and in 9.6% of the cows (Cows' OR=1.5, c.i. 95%OR =0.9-2.4, p=0.08).The mean number of days from calving until an eventual mastitis diagnosis was 8 in both heifers and cows. The diagnosis was made on the calving date in 2 heifers and in 10 cows. The rearing environment variable (SLATS) did not contribute significantly as a single independent variable in analysis of mastitis incidence (OR=1.0, c.i. 95%OR = 0.3-3.7, p=0.97) ( Table 2). However, the cubicle refusal variable (CU-BREF) indicated a positive association, approaching statistical significance (OR=2.2, c.i. 95%OR =0.9-5.4, p=0.08) ( Table 2). Adding the interaction term to the analyses resulted in non-convergence and did not provide further information. The PAF value for the contribution of CUBREF to MAST was found to be 0.21 (-0.03 to 0.32 when employing respectively the lower and upper 95% confidence limits of the OR). A strong association was detected between rearing in slatted floor pens (n=328) and the occurrence of cubicle refusal (n=106) by the heifers (OR=5.1, c.i. 95%OR =1.8-20.2, p<0.01).

Discussion

Instead of sampling farms throughout the country, we included all cubicle-housed herds in a certain geographical area. Oppland county was chosen because of the area's accessibility in relation to the Norwegian School of Veterinary Science, and known to have many dairy farms with cubicle sheds of various sizes located in geographically diverse environments.

To ensure a fairly large number of observations, the farmers were employed as observers.  had no previous training for this task, and in order to achieve a certain degree of standardization, the behaviour-observation process was made as simple as possible, demanding little need for interpretation or special knowledge of behaviour. Each farmer was also given instructions verbally of how to record the requested data. Systematic associations between an actual observation and the probability of that value being missing in the data set, such as consistent under-reporting of e.g. cubicle refusal, were considered to be unlikely. The risk of data bias due to missing values was therefore regarded as acceptably low. The data set contained observations from many different herds. One must assume that there was a stronger degree of dependence between the observations within one herd than between observations from different herds. On this background the total set can be seen as consisting of a number of data subsets or clusters. Logisticbinomial regression with random effects is a procedure that allows for the possibility of taking clustering factors into account (Statistics and Epidemiology Research Corporation 1991) and it was therefore chosen for statistical analysis of the data. Cubicle refusal was higher than previously found by Kjaestad & Myren (2001). Using a similar classification method for cubicle use, they reported that 6% of the cows showed cubicle refusal. However, in the present study, cubicle use recording was by design associated with late pregnancy, while in the cited study there was no association between recording cubicle refusal and pregnancy status. The prevalence of cubicle refusal was higher in the heifers than in the cows. This is as expected because most of the heifers had been reared in facilities lacking cubicles and, in accordance with the traditional practice, transferred to the cubicle yard few weeks before expected calv-ing. The heifers were therefore in a phase of learning how to use the cubicles when their behaviour was recorded. Some of the difference in cubicle refusal between heifers and older cows may have been due to culling of animals showing the undesirable behaviour because their udders become dirty, resulting in more laborious preparation of the cow before milking. The practice of grazing has been shown to lower the risk of mastitis in heifers. Waage et al. (1998) found that the incidence is reduced during the grazing months in herds that are kept on pasture compared to herds practicing zero grazing. An association between grazing/keeping heifers outdoors and decreased mastitis risk is also reported by Bendixen et al. (1986) and Schukken et al. (1988). Some of the heifers in the present study had evidently been out on pasture for a shorter or longer time, as pasture was indeed the reported calving location in a few cases. However, because we did not know the duration of the pasture period of these heifers and, on the other hand, were unable to determine whether the remaining heifers also had been grazed, we could not include pasture as a reliable variable in our analysis. It is therefore difficult to speculate whether this may have influenced the results. Nevertheless, it is likely that grazing was practiced for either all or none of the heifers in the herd, so that some of the eventual variation due to this practice will have been addressed by including the herd clustering factor in the analyses. The result of the analysis using cubicle refusal instead of rearing accommodation indicates that the former variable is the most important as a possible risk factor. Interaction between the independent variables did not seem to be important, as the analyses did not improve after adding the interaction term. Concerning cubicle refusal per se, we know that a number of the bacteria species normally present in faeces are potential mastitis patho-gens, e.g. faecal streptococci and Escherichia coli (Bramley & Dodd 1984). The pathogenic bacteria can enter the udder when the cow is resting on a very contaminated surface like the alley of a cubicle house. Moreover, the moisture and draft from the slatted floor of a cubicle house cause chilling of the udder of cows refusing to rest in cubicles. Local chilling of the udder decreases resistance to infection, and is sufficient by itself to cause acute mastitis (Dyrendal & Ewbank 1968). The PAF value for cubicle refusal that was found in the present study is relatively large (0.21). We consider this to be an important result, because it means that perfect control of cubicle refusal may lead to a significant reduction of mastitis in first calved heifers during the first month post partum. In the present study, rearing accommodation did not contribute significantly to the mastitis incidence analysis when being the sole independent variable. The finding was unexpected, because we did find a tendency for cubicle refusal to be significant, and cubicle refusal was also significantly associated with rearing in slatted floor accommodation. The absence of a detectable contribution by rearing accommodation alone in the present material may be due to the uneven distribution between the 2 rearing environment categories, i.e. the number of heifers that were reared in other accommodation than slatted floor pens was relatively small. Previously, other studies have indicated that heifer rearing accommodation is indeed a mastitis risk factor. A study by Pettersen (1981) reports that heifers reared in group pens have a considerably higher risk of being diagnosed with mastitis at first milking than those reared in tie stalls. This is supported by the results of Østerås et al. (1994), who studied the differences in housing and management between herds with especially high or low mastitis-associated costs. Among other factors, they con-clude that herds in which heifers were kept in group pens have a higher tendency to be found in the high cost group compared to the herds in which other heifer accommodation is employed. Neither of the cited studies discloses the actual flooring type in the heifer pens, but it is probably safe to assume that the majority had slatted floors, as this is the most common flooring type found in such accommodation throughout this country. However, floor type is certainly not the only plausible risk factor common to group pens, and other factors such as sucking among heifers were indeed discussed in the cited studies. The discrepancy between the cited studies and the present one in respect to the effect of accommodation may be due to differences in material sizes and group sizes. In our study, the group reared in other accommodation than pens was very small. The material studied by Østerås et al. (1994) was considerably larger than that of the present study. Pettersen's (1981) material size is comparable to ours, but it has a higher mastitis incidence, making it more likely to detect effects of rearing environment. It also addresses mastitis at first milking, indicating that the disease may have been present before calving. In the present study, mastitis before calving was not monitored, and in the few instances when mastitis was found at first milking, the case was included in the analysis as another eligible case. Therefore, the aetiology of the mastitis cases may be different. We conclude from the present study that cubicle refusal around calving is primarily a problem of heifers, and that cubicle refusal behaviour constitutes a mastitis risk factor for dairy heifers.

Sammendrag

Gangligging og kvigebinge som mulige risikofaktorer for mastitt hos kviger i liggebåsfjøs.

Formålet med studien var å undersøke forekomsten av gangligging hos kviger og kyr i løpet av den siste uken før kalving, samt å analysere eventuelle sammenhenger mellom oppstalling på spaltegolvsbinge, gangligging og klinisk mastitt hos kvigene i de første 30 dager etter kalving. Femtini av de i alt 65 besetningene med løsdrift i Oppland fylke i 1990 ble inkludert i studien. Det ble utformet et spørreskjema hvor bonden noterte kyrnes/kvigenes foretrukne liggeplass den siste uka før kalving. Opplysninger om sjukdomsbehandlinger ble hentet fra helsekortordningens data i Kukontrollens database. Mastittforekomst hos kvigene i løpet av 30 dager etter kalving ble analysert ved logistisk regresjon med besetning som tilfeldig effekt-variabel, og type av oppstalling for kvigene før overføring til kuflokken og gangligging som uavhengige variable. Gangligging forekom hos 29% av kvigene, men bare 3% av kyrne, og det ble påvist en tendens til at gangligging hos kvigene hadde sammenheng med økt mastittfrekvens (c.i. 95%OR =0.9-5.4, p=0.08). Tjueen prosent (0-32%) av mastittene i denne populasjonen kunne tilskrives gangligging som årsaksfaktor (PAF=0.21).

Cubicle refusal and rearing accommodation 125Acta vet.scand. vol. 42 no. 1, 2001

Table 1 .
1Cubicle use by cows and heifers in cubicle sheds throughout the final week of pregnancy.Cubicle use throughout
Age group

the final week of
Heifers expecting first calf
Cows expecting second calf
Older cows
pregnancy
(n 1 =368)
(n 2 =261)
(n 3 =415)

Consistent or occasional
107 (29%)
8 (3%)
12 (3%)
cubicle refusal, total or
with hind quarters

Consistent cubicle use
261 (71%)
253 (97%)
403 (97%)

OR of cubicle refusal in heifers compared to cows: 13.29 (c.i. 95%OR =7.89-22.61, P<0.01)

Table 2 .
2Results of logistic regression analysis of cubicle refusal and rearing accommodation as risk factors for mastitis during the first 30 days after calving. (The total number of heifers in the population at risk was 399. Analysis not possible for 58 records due to missing values for at least one variable)Models:
MAST=a 1 + b 1 SLATS; MAST=a 2 + b 2 CUBREF
a n being the regression constant (general mean), and b n the regression coefficient of the independent variable.

Name of term Explanation
a
b
SE
P
OR
c.i. 95%(OR)

SLATS
Rearing accommodation of heifer
-2.72
-0.03
0.68
0.97
0.97
0.26-3.69
(1=group pen, 0=other)

CUBREF
Cubicle refusal throughout the final -3.01
0.80
0.46
0.08
2.23
0.92-5.44
week of pregnancy (1=yes, 0=no)

Acta vet. scand. vol. 42 no. 1, 2001
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