Browsing by Author "Bakir, G."

Now showing 1 - 4 of 4

Classification Tree for Low Birth Weight Rate of Calves
(2009) Mirtagioglu, H.; Keskin, S.; Bakir, G.
The aim of study was to determine effects and interactions of age of first insemination, first calving age, calving age, calving interval, lactation order, dry period, calving month and sex of calf variables on low birth weight rate in calves by using of Classification tree (CT) method. For this the observations obtained from 596 animal materials were used. As a result, calving interval, calving age and calving month were found as significant predictor variables for low birth weight rate of female calves. On the other hand, none of these (calving interval, calving age and calving month) variables was found as significant for male calves.
Determination of the Effective Factors for 305 Days Milk Yield by Regression Tree (Rt) Method
(2010) Bakir, G.; Keskin, S.; Mirtagioglu, H.
The purpose of this study was to determine the effects of dry period, lactation parity, farm, calving season and age on 305 days milk yield using Regression Tree (RT) method. For this purpose 3315 data of 735 Holstein-Friesian raised in Ceylanpinar, Reyhanli and Tahirova State Farms were analyzed. Dry period-lactation parity and farm-calving season and calving age were determined to affect 305 days milk yield at the first, second and third degree factors, respectively. The 305 days milk yield was affected by dry period, calving age and season and being of the dry period around ideal period (60 days) affected milk yield positively. It was suggested that dry period should be around 60 days and some precautions to decrease the adverse effects of heat on milk yield are required to be taken. © Medwell Journals, 2010.
Genetic Parameters for Direct and Maternal Effects and an Estimation of Breeding Values for Birth Weight of Holstein Friesian Calves
(Scientific Issues Natl Centre Agrarian Sciences, 2012) Kaygisiz, A.; Bakir, G.; Yilmaz, I.
KAYGISIZ, A., G. BAKIR and I. YILMAZ, 2012. Genetic parameters for direct and maternal effects and an estimation of breeding values for birth weight of Holstein Friesian calves. Bulg. J. Agric. Sci., 18: 117-124 In this study, genetic and phenotypic parameters for birth weight in Holstein calves raised at Tahirova and Polatli State Farms were estimated. Analysis of the results showed that the least squares means of birth weight were 38.71 +/- 3.56 and 37.53 +/- 2.09 kg for the calves raised at state farms at Tahirova and Polatli, respectively. The effects of birth year, season and sex on birth weight were significant (P < 0.05) or highly significant (P < 0.01). The effect of calving parity on birth weight was highly significant (P < 0.01) for state farm at Tahirova, but insignificant for state farm at Polatli. Direct heritability (h(d)(2)), maternal heritability (h(m)(2)), total heritability (h(T)(2)) and the fraction of variance due to maternal permanent environmental effects (c(2)) were 0.15, 0.56, 0.12 and 0.0004, respectively for calves raised at state farm at Tahirova. Direct heritability (h(d)(2)), maternal heritability (h(m)(2)), total heritability (h(T)(2)) and the fraction of variance due to maternal permanent environmental effects (c(2)) were 0.04, 0.002, 0.039 and 0.002, respectively for calves raised at state farm at Polatli. It was concluded that the effects of environmental factors should be eliminated for the implementation of effective selection program to be conducted on birth weight in Holstein calves.
Regression Tree Analysis for 305 Day Milk Yield in Holstein Cows
(indian veterinary Journal, 2008) Mirtagioglu, H.; Keskin, S.; Bakir, G.
305 - day milk yield in cows is one of the most important traits in breeding studies. Therefore, it is important to determine and investigate the relationships between the 305-days milk yield and other related traits. In the present study, relationships between 305-day milk yield and related traits as well as their interactions were analyzed by using regression tree analysis (RT).