A study on the milk yield and the content of milk of the sheep of the Pleven black head breed
2008
Panajotov, D., Thracian University, Stara Zagora (Bulgaria) | Simeonov, M., Institute of Forage Crops, Pleven (Bulgaria) | Iliev, T., Thracian University, Stara Zagora (Bulgaria) | Zheleva, N., Thracian University, Stara Zagora (Bulgaria)
The study was carried out with 1039 ewes from the two main breeding flocks of the Pleven Black head breed (PBH) – at the Institute of Forages – Pleven (IF) and in the village of Komarevo, Pleven district. The phenotypic characteristics of the flocks consisted of the traits lactation length, lactation yield, milk yield for 200 days. The content of milk was determined for 30 ewes (ram-producers) at II lactation. It was found, that the sheep of Komarevo were with a considerably longer lactation period at I and II lactation compared to their contemporaries in the flock of IF. The average lactation milk yield for I and II lactation of the ewes in IF was about 192 l, and that of the ewes in Komarevo – 199 l. The production year as a complex factor caused a very big influence on the phenotypic appearance of that trait, especially in the IF flock. The 200-days milk yield of the ewes in IF for most of the studied years was higher compared to that of the flock in Komarevo. For the 120-days lactation period the superiority (over 20 l in average) was in favour of the Komarevo flock. The studied ewes excelled with very good characterstics of the milk composition. The average fat content was in the range of 5.96 to 7.64%, of the protein – from 5.70 to 6.19%, and for the dry matter – from 17.19 to 18.76%, and the three traits followed an increasing tendency with the progress of the lactation. For the lactose and dry non-fat residue the average values were very close – respectively from 4.22 to 4.80% and from 10.89 to 11.30%. The total number of the somatic cells in the milk was relatively high – 687.7 thsnds./ml for the first test day, 836.2 thsnds./ml for the third and 424.6 thsnds./ml for the forth test day (at the end of the lactation).
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