İsmail Keskin

Application of the Support Vector Machine to Predict Subclinical Mastitis in Dairy Cattle

This study presented a potentially useful alternative approach to ascertain the presence of subclinical and clinical mastitis in dairy cows using support vector machine (SVM) techniques. The proposed method detected mastitis in a cross-sectional representative sample of Holstein dairy cattle milked using an automatic milking system. The study used such suspected indicators of mastitis as lactation rank, milk yield, electrical conductivity, average milking duration, and control season as input data. The output variable was somatic cell counts obtained from milk samples collected monthly throughout the 15 months of the control period. Cattle were judged to be healthy or infected based on those somatic cell counts. This study undertook a detailed scrutiny of the SVM methodology, constructing and examining a model which showed 89% sensitivity, 92% specificity, and 50% error in mastitis detection.

Lactation curve traits of Holstein cows raised at Polatlı State farm.

minin grafiksel gösterimi laktasyon eğrisi olarak tanımlanır. Doğumla başlayan süt verimi belirli bir süre (2-6 hafta) artarak maksimum düzeye erişir. Bu maksimum üretim düzeyi bir süre (ortalama 1 ay) devam eder ve daha sonra başlangıçtaki artıştan daha düşük bir hızla süt verimi azalarak, ineğin kuruya çıkması ile laktasyon sona erer. Genetik ve çevresel faktörlerin etkisiyle şekillenen ve buzağılama ile başlayıp kuruya çıkma ile son bulan süt verimindeki değişiklikler laktasyonun seyri, laktasyonun akışı veya laktasyon eğrisi olarak adlandırılır. Laktasyon eğrisinin inişe geçen kısmının Kafkas Univ Vet Fak Derg 15 (3): 437-442, 2009 DOI:10.9775/kvfd.2009.034-A RESEARCH ARTICLE

Fitness of four different mathematical models to the lactation curve of Brown Swiss cows in Konya Province of Turkey

The aim of this study was to investigate the fitness of Incomplete Gamma (WD), Exponential (WIL), Mixed Log (MIL) and Polynomial Regression (AS) models to the lactation curve of Brown Swiss Cows. Data were collected from 143 Brown Swiss cows raised on the Alt?nova State Farm in Konya Province, Turkey. Milk yield was recorded monthly, and milk records were started at the third week of lactation (mean = 16.9 day, SD = 0.7). Total milk yields estimated by the four models were very close to real total milk yield. The models were found to be adequate for estimation of milk yield. The MIL model underestimated the peak yield significantly. The differences between peak yields of the models and real peak yields were not significant and ranged from 27.70 to 29.01 L. All models forecasted peak time earlier than real peak time. The differences for the persistency values of the four models were significant. The AS models persistency value was nearly equal to the real persistency value (77.56 vs. 77.59%). R2 values of...

Relationship between Persistency Values Defined with Various Methods and Some Lactation Traits of Brown Swiss Cattle in Turkey

Abstract Zülkadir, U., Aytekin, I. and Keskin, 1. 2008. Relationship between persistency values defined with various methods and some lactation traits of Brown Swiss cattle in Turkey. J. App. Arum. Res., 34: 137–141. The study was conducted to compute the persistency values of the animals in different lactation periods with various methods drawing upon 3695 test day milk yield of 182 lactations of Brown Swiss cattle in Konya Konuklar Agricultural Enterprise. The computed persistency values of the animals in the first lactation were different (P<0.01) from the other lactations. Lactation number (P<0.05) and calving seasons (P<0.01) effected persistency values. The phenotypic correlation of the methods within the group and with lactation milk yield, lactation period, daily average milk yield and daily maximum milk yield were highly significant (P<0.01). The Sblkner and Fuchss model based on standard deviation of 305 d lactation period showed the highest phenotypic correlation for lactation milk yield (LMY), daily average milk yield (DAMY), daily maximum milk yield (DMMY), and the best fit to the data collected from Brown Swiss cattle and allowed a suitable description of the shape of the lactation curve.