Mousavi Shalaleh, Haghparast Alireza, Mohammadi Gholamreza, Tabatabaeizadeh Seyed-Elias
Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran;
Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran; ; Veterinary Medicine, Cell and Molecular Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran;
Vet Res Forum. 2014 Spring;5(2):135-9.
The purpose of this study was to determine the prevalence of bovine leukemia virus (BLV) in Khorasan Razavi and Khorasan Shomali provinces which are the main provinces located in the northeast of Iran. Total number of 429 blood samples were collected from industrial dairy herds. The samples were categorized based on province, age (2-3, 4-6, and 7-10 years old), calving (≤ 2, 3-5, and > 5) and herd size (≤ 100, 101-250, and > 250) and examined by indirect ELISA. The results of this study showed that 109 (25.4%) out of 429 serum samples were BLV seropositive. The BLV prevalence among cattle of dairy herds of Khorasan Razavi and Khorasan Shomali provinces were 29.8% and 1.5%, respectively. The results showed that the number of seropositive animals was increased significantly with the age (p < 0.05). The infection rate in animals 2-3, 4-6 and 7-10 years old were 12.1%, 26.7% and 45.6%, respectively. It was shown that BLV prevalence according to calving ≤ 2, 3-5 and > 5 was 15.5%, 33.0% and 42.9%, respectively, with a significant difference between calving ≤ 2 and > 5 (p < 0.001). The prevalence of BLV among herd size of ≤ 100, 101-250 and > 250 was 19.7%, 14.3% and 42.1%, respectively, which was significantly higher in herds with more than 250 cattle (p < 0.05). This study revealed that BLV infection in dairy herds of northeast of Iran was influenced by geographical location (province), age, calving and herd size.
本研究的目的是确定位于伊朗东北部的主要省份呼罗珊拉扎维省和呼罗珊绍马利省牛白血病病毒（BLV）的流行情况。从工业化奶牛场收集了429份血样。这些样本根据省份、年龄（2至3岁、4至6岁和7至10岁）、产犊情况（≤2次、3至5次和>5次）以及牛群规模（≤100头、101至250头和>250头）进行分类，并通过间接ELISA法进行检测。本研究结果显示，429份血清样本中有109份（25.4%）为BLV血清阳性。呼罗珊拉扎维省和呼罗珊绍马利省奶牛场牛群中BLV的流行率分别为29.8%和1.5%。结果表明，血清阳性动物的数量随年龄显著增加（p<0.05）。2至3岁、4至6岁和7至10岁动物的感染率分别为12.1%、26.7%和45.6%。结果表明，根据产犊情况≤2次、3至5次和>5次，BLV的流行率分别为15.5%、33.0%和42.9%，产犊≤2次和>5次之间存在显著差异（p<0.001）。牛群规模≤100头、101至250头和>250头的牛群中BLV的流行率分别为19.7%、14.3%和42.1%，在牛数超过250头的牛群中显著更高（p<0.05）。本研究表明，伊朗东北部奶牛场的BLV感染受地理位置（省份）、年龄、产犊情况和牛群规模的影响。
