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document
Effects of supplementation of whole corn germ on reproductive performance , calf performance , and leptin concentration in primiparous and mature beef cows . A 2-yr study using primiparous and multiparous , spring-calving , crossbred beef cows was conducted to evaluate the effects of supplemental whole corn germ on reproductive performance , calf performance , and serum leptin concentrations . Each year , cows were blocked by age and BCS and assigned randomly to one of three treatments : PRE ( n = 115 ) cows received 1.14 kg/d ( DM basis ) of whole corn germ for approximately 45 d before calving ; POST ( n = 109 ) cows were fed 1.14 kg/d of whole corn germ for approximately 45 d after calving ; and control cows ( n = 118 ) were fed similar energy and protein from dry-rolled corn ( 1.82 kg of DM/d ) for 45 d before and after calving . Additionally , PRE cows were grouped with controls after calving , and POST cows were grouped with control cows before calving , so that corn germ-supplemented cows received the control supplement in the alternate feeding period . Cow BW ( 538 +/- 13 kg ) and BCS ( 5.4 +/- 0.13 ) did not differ among treatments at any time during the experiment . Calf birth weight ( 39 +/- 2 kg ) , weaning weight ( 225 +/- 7 kg ) , and age-adjusted weaning weight ( 234 +/- 8 kg ) did not differ because of dam supplementation regimen . Treatment did not affect the proportion of cows exhibiting ovarian luteal activity before the start of the breeding season ( 67 % ) or pregnancy rate ( 91 % ) . The interval from exposure to bulls until subsequent calving did not differ ( P = 0.16 ) among PRE ( 298 +/- 2.3 d ) , POST ( 303 +/- 2.6 d ) , and control ( 304 +/- 2.3 d ) cows . Leptin concentrations did not differ among treatments and were 2.15 +/- 0.75 , 1.88 +/- 0.76 , and 1.91 +/- 0.75 ng/mL for control , POST , and PRE cows , respectively . Age and week relative to calving influenced leptin concentration . Primiparous cows had similar leptin concentrations to 3-yr-old and mature cows for wk -7 and -6 relative to calving , but lower ( P < 0.10 ) concentrations than mature cows for wk -5 , and lower ( P < 0.05 ) concentrations than either 3-yr-old or mature cows for wk -4 to +7 relative to calving . Serum leptin was correlated with BCS ( P < 0.0001 ; r = 0.35 ) at initiation of the feeding period and was correlated with BCS ( P = 0.02 ; r = 0.12 ) and weight ( P < 0.01 ; r = 0.14 ) at the completion of the supplement period , but it was not correlated with initial BW or interim BCS . Calving interval was not correlated ( P > 0.12 ) with weekly measures of serum leptin concentration . Supplementing beef cows with whole corn germ had no effect on cow performance , calf performance , or serum leptin concentrations of cows .
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Intervention_Pharmacological
supplemental whole corn germ
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Intervention_Physical
blocked by age and BCS and assigned randomly to one of three treatments : PRE ( n = 115 ) cows received 1.14 kg/d ( DM basis ) of whole corn germ for approximately 45 d before calving ; POST ( n = 109 ) cows were fed 1.14 kg/d of whole corn germ for approximately 45 d after calving ; and control cows ( n = 118 ) were fed similar energy and protein from dry-rolled corn ( 1.82 kg of DM/d ) for 45 d before and after calving
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Intervention_Physical
grouped with controls after calving , and POST cows were grouped with control cows before calving , so that corn germ-supplemented cows received the control supplement in the alternate feeding period
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Intervention_Pharmacological
.
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Outcome_Physical
reproductive performance
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Outcome_Physical
calf performance
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Outcome_Physical
leptin concentration
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Outcome_Physical
reproductive performance
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Outcome_Physical
calf performance
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Outcome_Physical
serum leptin concentrations
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Outcome_Physical
Cow BW
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Outcome_Physical
Calf birth weight
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Outcome_Physical
weaning weight
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Outcome_Physical
age-adjusted weaning weight
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Outcome_Physical
ovarian luteal activity
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Outcome_Physical
Leptin concentrations
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Outcome_Physical
leptin concentrations
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Outcome_Physical
serum leptin concentration