Environmental influences on age at first lambing and lambing interval in Yankasa sheep
نویسندگان
چکیده
منابع مشابه
Effects of ewe age and season of lambing on prolificacy in US Targhee, Suffolk, and Polypay sheep.
Factors affecting ewe prolificacy (number of lambs born per ewe lambing) were evaluated using records on 9705 Targhee, 12,721 Suffolk, and 7231 Polypay lambings from flocks participating in the US National Sheep Improvement Program. Factors considered were ewe age and season of lambing. Prolificacy was affected by age of the ewe (P<0.001) and was highest for ewes lambing between 4 and either 7 ...
متن کاملEffect of weaning age on hair sheep lamb and ewe production traits in an accelerated lambing system in the tropics.
This study was designed to evaluate the impact of weaning age on lamb and ewe productivity in an accelerated lambing system. St. Croix White (STX) and Dorper × St. Croix White (DRPX) lambs were assigned at birth based on breed, gender, and litter size to be weaned at 63 (Early-1; 106 lambs and 68 ewes) or 90 d of age (Late-1; 99 lambs and 60 ewes) in Exp.1 or at 63 (Early-2; 77 lambs and 57 ewe...
متن کاملEffect of early weaning and hormone treatments on induction of estrus, conception and lambing of fall-lambing Karakul ewes.
The effects of early weaning and exogenous hormones on postpartum estrus, conception and lambing performance were evaluated with 124 fall-lambed Karakul ewes. The broad outline of the experiment consisted of two lactation periods (nursing for 48 hr or 60 days postpartum) and four hormone treatment groups as follows: (1) a single injection of 2 mg estradiol-17/3 on day 4 postpartum and on the sa...
متن کاملLambing performance of Morlam and Dorset ewes under accelerated lambing systems.
Two accelerated lambing systems, Morlam using Morlam sheep (USDA, Beltsville 1966 to 1975) and Camal using Dorset ewes (Cornell 1978 to 1981), were evaluated for first lambing ages, interlambing intervals and conception probabilities. Morlam ewes were continuously exposed to rams over the year, while Camal Dorset ewes were exposed every other month. Morlam lambs were mated as early as 367 d of ...
متن کاملNocturnal melatonin and prolactin plasma concentrations in sheep selected for fertility in autumn lambing'.
Ewes selected for fertility in autumn lambing were used to evaluate correlated responses in nocturnal hormone levels. Four jugular blood samples were obtained during nighttime in August from each of 113 selected and 69 control ewes. Melatonin levels were lower for selected ewes (143 +/- 14 pg/mL) than for control ewes (184 +/- 13 pg/mL), and melatonin levels decreased with increases in estimate...
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ژورنال
عنوان ژورنال: Agro-Science
سال: 2000
ISSN: 1119-7455
DOI: 10.4314/as.v1i1.1468