Document Type : Research Paper
Authors
1
Department of Animal Science, Faculty of Agriculture, University of Zabol, Zabol, Iran
2
Department of Animal Science, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran
3
Deputy of Animal Breeding and Improvement Center, Ministry of Jihad Agriculture, Karaj, Iran
4
Department of Animal Breeding and Genetic, Animal Science Research Institute, Karaj, Iran
5
Department of ostrich. Special domestic animals institute research institute of Zabol, Zabol, Iran
Abstract
One of the factors affecting milk production is climatic conditions. While, in this research, the effect of different climates of the country on the productive traits of Holstein dairy cattle herds throughout the country has been investigated. The productive traits included the average production of milk, fat and protein between 2007 and 2021 for the number of 325.040 heifers from 270 herds. The regions of the country were divided into five climates with different temperature and humidity. Based on the obtained results, BWk climate had the highest production despite unfavorable climatic conditions. However, Dsa climate, which has the third place in milk production, has performed best in the amount and percentage of fat and protein, however, considering that this climate had the lowest number of herds among the climates, it generally performs better in production traits than other climates. Moreover, in the period from 2007 to 2021, when increasing economic problems, such as the increase in inflation and currency rates, as well as the removal of livestock input subsidies, made it difficult for livestock farmers to cover the costs of providing animal feed, all regions except Dsa region experienced a decrease in the number of herds. From the findings of this research, it can be concluded that the climatic effect in terms of heat stress for livestock and in terms of the suitability of weather conditions for planting fodder and providing livestock feed can have a decisive effect on the productive traits of livestock.
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