Milk productivity, reproductive performance, hematological and clinical indicators of holstein, brown swiss, simmental, and jersey breeds of cows under Armenian agro-climatic conditions

L.M. Minasyan¹, H.R. Vardanyan¹, Zh.T. Chitchyan², M.H. Zadayan³*, J.T. Simonyan⁴, N.A. Shahazizyan¹, M.S. Mirzoyan¹ and L.L Simonyan¹

¹Scientific Centre for Risk Assessment and Analysis in Food Safety Area of the Ministry of Economy of the Republic of Armenia, 107/2 Masis Highway, Shengavit, AM0071 Yerevan, Republic of Armenia
²Armenian National Agrarian University, Yerevan, Teryan 74, AM0009 Yerevan, Republic of Armenia
³Center for Agricultural Research and Certification, State Non-Commercial Organization at the Ministry of Economy, Yerevanyan highway 2nd block, building 4, AM1139 Merdzavan, Republic of Armenia
⁴Ministry of Economy of the Republic of Armenia, Mher Mkrtchyan 5, AM0010 Yerevan, Republic of Armenia
*Correspondence: mhzadayan@gmail.com

Abstract:

The research was conducted on the farms of ‘Himnatavush’ Foundation and ‘Agroholding Armenia’ LLC in the Tavush and Lori regions of the Republic of Armenia. This study aims to fill a research gap regarding the adaptability of elite dairy breeds in the South Caucasus under variable agro-climatic conditions. The scientific and practical goal of the work is to conduct, for the first time, a comparative study of the milk productivity, reproductive capacity, and hematological and clinical indicators of Holstein, Brown Swiss (Schwyz), Simmental, and Jersey cattle breeds imported into the Republic of Armenia from various European countries in recent years, as well as cows born and raised locally (local reproduction). The study is being carried out in two farms located in different agro-climatic zones of the Republic. At the farms of ‘Agroholding Armenia’ LLC and the ‘Himnatavush’ Foundation, the age at first calving of both imported full-grown cows of Holstein, Brown Swiss, Simmental, and Jersey breeds and their locally born and raised first-calf heifers corresponded to breed-specific norms. The service period for cows of all breeds exceeded the desirable range (80–90 days), ranging from 93.8 to 115.6 days. However, the reproductive capacity coefficient ranged between 92.9–97.3, which is considered a good indicator. Hematological and clinical parameters of all cows remained within physiological norms. Jersey cows exhibited slightly better adaptation markers. The study confirms the successful acclimatization of these breeds to Armenia’s diverse agro-climatic zones and supports the continued use of these high-yielding breeds for sustainable dairy development.

Key words:

adaptation traits, age at first calving, breed comparison, milk productivity, physiological indicators, reproductive traits

Relation between first lactation milk yield and functional traits in dairy cows

Iv. Marinov¹, V. Valchev¹, D. Dimov² and T. Penev²*

¹Trakia university, Faculty of agriculture, Department of Animal Husbandry -Ruminants and Dairy Farming, BG6000 Stara Zagora, Bulgaria
²Trakia University, Faculty of Agriculture, Department of Applied Ecology and Animal Hygiene, BG6000 Stara Zagora, Bulgaria
*Correspondence: tonchopenev@abv.bg

Abstract:

The aim of the study was to analyze the relationship between first lactation milk yield (FLMY) and age at first calving (AFC), longevity and productive life in dairy cows. The study covered 944 Holstein cows housed in 5 dairy cattle farms in Bulgaria. All cows from the five farms culled in the period 2012–2018 with FLMY data were included. The average AFC for all culled cows included in the study was relatively high for the Holstein-Friesian breed – 29.75 months. The average FLMY of the herds included in the study was 7,660.94 kg with significant herd variation from 5,899.09 kg to 8,646.0 kg. Significant effect of the herd (P < 0.001), AFC and the associated effect of the herd and AFC (P < 0.05) on the average FLMY were found. The highest FLMY was reported in primiparous with AFC of 28–30 months – 7,860.8 kg, and the lowest in those with AFC ≤ 24 months – 7322.8 kg. In the herd with the lowest average FLMY – 5,899.09 kg 27.5% of the heifers had calved at age over 34 months. A statistically significant effect of AFC (P < 0.001) was found on longevity, whereas the productive life was significantly influenced by FLMY (P < 0.05). A tendency for higher longevity for cows with higher AFC of 34–37 months and over 37 months – 5.9 and 5.8 years, respectively was observed. The lowest were the longevity values for cows calved at age up to 24 months – 4.9 years. The cows with the lowest average FLMY (up to 4,000 kg) had the shortest productive. Both very low and high AFC were associated with lower first lactation cow productivity and shorter productive life. The losses for farmers were greater when keeping a high AFC in heifers, which increases the cost for housing them, and the lower productivity and longer productive life reduce the probability.

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