Determination of factors affecting pregnancy rate in Turkish Saanen goats

Abstract

Reproductive performance in goats is one of the important trait which has a major effect on commercial farm income. The objective of this study was to evaluate the factors effecting reproductive performance of Turkish Saanen goats with using Logistic Regression. The records of Turkish Saanen goats, aged 2 - 4 (2.05 ± 1.19), were used in this study. Data were analyzed with using stepwise multivariate logistic regression analyses. The response variable was pregnancy and the model included milk yield, insemination type and insemination day. As a result, milk yield at the insemination day (P<0.001) was one of the major factor with insemination type (P<0.05) and the increase in insemination day (P<0.05) was tend to be significant factor for the likelihood of pregnancy and were determined as the main factors. Milk yield at the insemination day 99.9% effects pregnancy and artificially inseminated goats were 2.4 times less likely to become pregnant than the naturally inseminated goats. The increase of insemination day also caused 30.0% increase in likelihood of pregnancy. As a conclusion, milk yield on the insemination day is the most significant factor affecting the pregnancy likelihood in Saanen goats. On the other hand, artificial insemination is not very effective to get higher pregnancy rates in Saanen goats

Keywords

• Insemination
• logistic regression
• milk yield
• pregnancy

Türk Saanen keçilerinde gebelik oranını etkileyen faktörlerin belirlenmesi

Abstract

Hayvanlarda üreme performansını etkileyeceği düşünülen birçok faktör farklı araştırmalarda incelenmiştir. Bu çalışmada, Saanen ırkı keçilerde gebeliği etkileyen faktörlerin Lojistik Regresyon yöntemi ile belirlenmesi amaçlanmıştır. Çalışmanın verileri, yaşları 2 ile 4 (2.05 ± 1.19) arası değişen 39 baş Saanen keçisine ait kayıtlardan oluşmaktadır. Tohumlama günündeki süt veriminin, tohumlama tipinin ve tohumlama gününün gebeliği etkilediği belirlenmiştir. Tohumlama günündeki süt veriminin gebeliği %99.9 olasılıkla etkilediği (P<0.001), suni tohumlanan keçilerde doğal tohumlananlara göre gebe kalma oranının 2.4 kat (P<0.05) azaldığı belirlenmiştir. Tohumlama yapılan gün sayısının artması da gebe kalmayı %30 oranında (P<0.05) arttırmaktadır. Sonuç olarak, tohumlama günündeki süt veriminin, Saanen keçilerde gebeliğin şekillenmesini etkileyen en önemli faktörlerden biri olduğu saptanmıştır. Ayrıca, Saanen keçilerde suni tohumlama uygulamasından etkin düzeyde gebelik elde edilemediği görülmektedir

Keywords

• Gebelik
• lojistik regresyon
• süt verimi
• tohumlama

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