takma, çiğdem university of ege - faculty of agriculture - department of animal science, Izmir, Turkey , işçi güneri, öznur university of muğla sıtkı koçman - faculty of science - department of statistics, Turkey , gevrekçi, yakut university of ege - faculty of agriculture - department of animal science, Izmir, Turkey

Investigation of Stillbirth Rate Using Logistic Regression Analysis in Holstein Friesian Calves

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logistic regression analysis is a method to determine the reason-result relationship of independent variable(s) with dependent variable, which has binary or multiple categorical structures. In this study, sex of calf, parity and calving year-season effects on stillbirth were analyzed with binary logistic regression analysis. Study material was obtained from the USA National Association of Animal Breeders collected among 2003-2005 with a total of 404460 birth records of single born calves. According to the results, sex of calf, parity and calving year-season effects on stillbirth were found statistically significant (P 0.05). The model showed good fit, based on Hosmer-Lemeshow goodness of fit statistics (P 0.12). When all variables were analyzed together in the same model, stillbirth rate of female calves compared to male calves was found to be more than 1.03 times higher. In addition, risk of stillbirth was decreased by increasing parity. On the other hand, the risk of stillbirth in summer calves was found to be higher than winter calves. In our country, data sets on stillbirth rates should be collected and risk factors that have an effect on stillbirth must be detected and then calf deaths could be controlled here, too.

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Holstein Friesian , stillbirth , logistic regression , calf

The Journal Of Ege University Faculty Of Agriculture

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