Effect of the year on the biological fertility in ewes from a synthetic population of Bulgarian milk with with two consecutive pregnancies in two consecutive calendar years
Nikola Metodiev
, Tanya Ivanova
Abstract: The aim of the study is to evaluate the influence of the year on the biological fecundity of sheep from the Synthetic population Bulgarian milk with two consecutive pregnancies, in two consecutive calendar years. The study was conducted with 171 ewes, raised in the experimental base of the IAS-Kostinbrod, in the period 2010 - 2021. The first fertilization was between 18 and 20 months of age. Breeding campaigns were conducted in the period July - September. All animals have had two consecutive lambings, in two consecutive calendar years. Biological fecundity is determined as a percentage based on the ratio of the number of live births and stillbirths to the number of lambed ewes. The reffect of the influence of year on fecundity was determined by one-way ANOVA. The effect of factor influence was determined by Fisher's F-test values. SPSS 21.0 computer program was used for statistical data analysis. The year had a significant effect on the variation of fecundity in first lambing ewes from the Sythetic population Bulgarian milk, (F=2.727, P<0.01). The average fecundity of all studied sheep at the first lambing was 126.90%, and at the second lambing - 122.81%. Ewes that at the first lambing realize a significant higher fecundity at the second lambing also realize a higher fecundity.
Keywords: effect of the year; fecundity; sheep; Synthetic population Bulgarian milk
Citation: Metodiev, N. & Ivanova, T. (2024). Effect of the year on the biological fertility in ewes from a synthetic population of Bulgarian milk with with two consecutive pregnancies in two consecutive calendar years. Bulgarian Journal of Animal Husbandry, 61(6), 8-13 (Bg).
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| Date published: 2024-12-16
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