نوع مقاله : مقاله پژوهشی
نویسندگان
بخش تحقیقات علوم دامی، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی گلستان، سازمان تحقیقات، آموزش و ترویج کشاورزی، گرگان، ایران،
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Background and objectives:
Selecting a breed with appropriate economic performance is one of the most challenging decisions that cattle farmers have to make. The Holstein breed has been imported to the country in the past few decades to increase milk production. This breed is scattered in different climates of Iran, including Golestan province, almost without previous study. Holstein is a breed with high milk production and sensitivity to heat stress. This breed in Golestan province did not have suitable reproductive and economic indicators. On the other hand, dual-purpose breeds, such as Montbéliarde, experience less thermal stress with less feed consumption. Therefore, the research was conducted to evaluate the performance of some reproductive traits and milk production of the Holstein breed, Montbéliarde breed, and hybrids to recommend a suitable breed in the region.
Materials and methods:
This study was carried out to evaluate the economic characteristics of some reproductive traits and milk production of Holstein cows with Montbéliarde cows and their crossbreeds in Golestan province in northern Iran. In this study, 395 cows were evaluated in the form of a completely randomized design. Indicators such as the age of first insemination and calving, open days, calving interval and the number of inseminations leading to fertility, length of pregnancy period, calf birth weight, and milk production Holstein, Montbéliarde, and 50:50 and 25 crosses: 75 Holstein x Montbéliarde were studied for 5 years in the same geographical point and same management. Meteorological data from 1390 to 1399 was analyzed with the approach of drawing the conditions of livestock breeding environment.
Results:
Investigating the results of long-term meteorological data showed that the temperature-humidity index has been above 68 for almost six months, and high-yielding dairy cows in this region are probably experiencing heat stress conditions. Based on the data of this research, Holstein cows showed more open days, so the number of inseminations leading to fertility in this breed increased, and the cost of maintenance, feed, as well as cost artificial insemination, and delay in pregnancy on the farm increased. The calving interval in the Montbéliarde breed, Holstein mixed with 75% Montbéliarde x 25% Holstein, 50% Holstein x 50% Montbéliarde was 398.31, 392.42, 387.59, and 421.72 days, respectively.
Conclusion
The results of this research showed that the reproduction efficiency of Montbeliarde breeds cows in Golestan province was better than Holstein breed, moreover, heavier calves were produced. It seems that heat stress conditions in the region were more effective in Holstein cows with higher milk production. In an economic evaluation of milk production and herd longevity without considering meat production, the Montbéliarde breed was better than Holstein. It seems that breeding the Montbéliarde breed in the warm and semi-tropical conditions of the north of Golestan province is a more suitable option than the Holstein breed.
کلیدواژهها [English]
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