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document
Effect of thermal stress , restricted feeding and combined stresses ( thermal stress and restricted feeding ) on growth and plasma reproductive hormone levels of Malpura ewes under semi-arid tropical environment . A study was conducted to assess the effect of thermal , nutritional and combined stresses ( thermal and nutritional ) on the growth , oestradiol and progesterone levels during oestrus cycles in Malpura ewes . Twenty-eight adult Malpura ewes were used in the present study . The ewes were randomly allocated into four groups , viz. , GI ( n=7 ; control ) , GII ( n=7 ; thermal stress ) , GIII ( n=7 ; restricted feeding ) and GIV ( n=7 ; combined stress ) . The animals were stall fed with a diet consisting of 60 % roughage and 40 % concentrate . GI and GII ewes were provided with ad libitum feeding while GIII and GIV ewes were provided with restricted feed ( 30 % intake of GI and GII ewes ) to induce nutritional insufficiency . GII and GIV ewes were kept in climatic chamber at 40°C and 55 % RH for 6 h a day between 10:00 and 16:00 hours to induce thermal stress for a period of two oestrous cycles . Parameters studied were body weight , oestrus incidences , plasma oestradiol 17-β , plasma progesterone , conception rate , gestation period , lambing rate , and birth weight of lambs . The results indicate that combined stress significantly ( p < 0.05 ) reduced body weight , oestrus duration , birth weight of lambs , and oestradiol 17-β whereas significantly ( p < 0.05 ) increased oestrus cycle length and progesterone . Furthermore , the results reveal that on comparative basis , ewes were able to better adapt in terms of growth and reproduction to restricted feeding than thermal stress . However , when restricted feeding was coupled with thermal stress it had significant ( p < 0.05 ) influence on body weight , average daily gain , oestradiol 17-β and progesterone concentrations . This showed that combined stress were more detrimental for these reproductive hormones in Malpura ewes under a hot semi-arid environment .
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Intervention_Other
restricted feeding
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Intervention_Other
combined stresses ( thermal stress and restricted feeding )
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Intervention_Control
control )
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Intervention_Other
thermal stress )
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Intervention_Other
restricted feeding )
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Intervention_Other
combined stress )
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Intervention_Other
stall fed with a diet consisting of 60 % roughage and 40 % concentrate .
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Outcome_Physical
body weight , oestrus incidences , plasma oestradiol 17-β , plasma progesterone , conception rate , gestation period , lambing rate , and birth weight of lambs
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Outcome_Physical
body weight , oestrus duration , birth weight of lambs , and oestradiol
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Participant_Sample-size
Twenty-eight
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Participant_Age
adult