12.07.2015 Views

AGRONOMIJAS VĒSTIS - Latvijas Lauksaimniecības universitāte

AGRONOMIJAS VĒSTIS - Latvijas Lauksaimniecības universitāte

AGRONOMIJAS VĒSTIS - Latvijas Lauksaimniecības universitāte

SHOW MORE
SHOW LESS
  • No tags were found...

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

<strong>AGRONOMIJAS</strong> VĒSTIS (Latvian Journal of Agronomy), No.10, LLU, 2008The TDM with the fixed DTD effect merged more cows in one subgroup. It gives an EBVwith more variations. The results showed that there are not significant differences between therankings of animals of EBV using TDM. The use of TD model produced EBV with higherreliability rates in the shortest time versus LM. Individual yields on test day can be the basis of agenetic evaluation system instead of estimates of yield during the first 305 days of lactation.ConclusionsEBV showed a large variation for all traits. EBV obtained in range from -1013.9 kg to1965.7 kg for milk yield. The lowest and highest values was obtained by the model with the fixedDTD effect. The results of these groups also showed largest variation of EBV (2968.8 kg). Thereare 6 bulls on all lists. There are bulls that showed similar ranking. Two bulls of HS breed haverespectively the 1 st and 2 nd position (HB No. 31352) and the 2 nd and 3 rd (HB No. 31415) position inall groups.The highest average EBV of fat yield are obtained in the II and IV group where the fixedDTD effect was included in the model, respectively 2.14 and 2.37 kg. Also the results of thesegroups showed the larger variation of EBV, respectively 132.43 and 131.30 kg. There were 8 bullson all lists when only the first 10 bulls are considered for the top list. The 1 st position of ranking ofall groups has a bull of DS breed (EBV from 69.3 to 93.6 kg). The bull of the HS breed has 2 nd and3 rd position of ranking in all groups (EBV from 46.1 to 85.3 kg).Using the model with fixed DTD effect results showed the highest variation of EBV ofprotein yield (respectively 91.74 and 93.56 kg) and the average EBV (respectively 1.86 and 1.99kg). In total 7 bulls included in the top list in all groups. The 1 st position has 2 bulls. The bull of ZSbreed showed EBV results from 35.5 kg to 37.3 kg when the fixed HTD effect was included in themodel. The bull of HS breed showed EBV results from 58.4 to 59.9 kg when the fixed DTD effectwas included in the model.The Spearman rank correlations (≥ 0.97) obtained by Kaya et al. (2003) indicated that theranking of animals for EBV for TD and 305-day milk yields closely correlated with each other andare in agreement with the results from this study.There are not significant differences between EBV of milk, protein yield in groups wherethe same HTD or DTD effect was included in the model and between all groups of fat yield(p

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!