Akademik Veri Yönetim Sistemi
Ankara Universitesi Veteriner Fakultesi Dergisi, cilt.63, sa.2, ss.179-186, 2016 (SCI-Expanded)
Fertility, milk yield and quality and health status of Holstein cattle reared at organic and conventional conditions were investigated. The research was conducted in two private farms, organic and conventional, in Aydın province where Mediterranean climate prevails. Data were collected from farm records and visiting fortnightly. The milk samples from bulk tank were used for milk quality a fortnightly basis, and for metals and aflatoxin M1 a monthly basis. The means in organic and conventional herds were 608.4±4.25 and 584.0±7.56 days (p<0.01) for first conception age; 104.1±0.37 and 111.1±0.46 days (p<0.001) for service period; 381.3±0.49 and 386.9±0.55 days (p<0.001) for calving interval; 5711.4±10.50 and 6382.8±15.32 kg (p<0.001) for corrected milk yield, respectively. The means in milk samples from organic and conventional herds were 12.38±0.07 and 12.52±0.07% for dry matter; 3.28±0.08 and 3.31±0.08% for fat; 352382±47888 and 316413±47679 cell/ml for somatic cell count; 0.0425±0.009 and 0.1375±0.094 ppb for aflatoxin M1 (p>0.05), respectively. Pb was not determined in both herd samples. The mean incidences in organic and conventional herds were 5.49 and 16.6% (p<0.01) for mastitis; 1.09 and 29.1% (p<0.001) for pneumonia; 6.59 and 23.6% (p<0.001) for chronic metritis, respectively. The results indicated that organic Holstein herd had longer age for first conception, but shorter service period and calving interval and lower milk yield than conventional Holstein herd. In addition, quality properties and levels of some metals and aflatoxin M1 of milk were similar in both herds. Besides, organic herd had lower incidences in terms of some diseases.