Serological evidence of bovine herpesvirus-1 (BoHV-1) infection in yaks (Peophagus grunniens) from the National Research Centre on Yak, India Sukdeb Nandi & Manoj Kumar Accepted: 18 January 2010 / Published online: 10 February 2010 # Springer Science+Business Media B.V. 2010 Abstract Bovine herpesvirus-1 (BoHV-1) causes a variety of disease syndromes including, respiratory, nervous and repro- ductive disorders both in domestic as well as wild bovines and the disease is prevalent throughout the world including India. In this study, serum samples of yaks were screened for serological evidence of BoHV-1 in a yak farm with history of abortion and kerato-conjuctivitis by competition-ELISA. The result of seroprevalence of BoHV-1 infections in yaks (Poephagus grunniens) revealed that the overall seropreva- lence was 60.1%. The sero-prevalence of BoHV-1 infections was highest in male calf (67.7%) followed by yak cows (62.6%), yak bulls (56.8%), and yak heifers (50.0%). Keywords Bovine Herpesvirus-1 . c-ELISA . Yak . Seroprevalence . India Introduction Yaks, large ruminant herbivores inhabiting in the high altitudes, provide milk, meat, wool, and can be used as pack animals. It belongs to the subfamily Bovinae and family Bovidae. Their natural habitat is in and around Himalayas, Northern states like Jammu and Kashmir, Himachal Pradesh, Uttarakhand, and North-Eastern states like Arunanchal Pradesh and Sikkim of India at an altitude of 2,500-5,000 m. The total yak population in India is about 38,000. The recent drastic decline in yak population all over the world including India has become a cause of concern to the development authorities and animal scientists. Further, yaks have been threatened by a large number of disease conditions responsible for reduced productivity, work ability, and reproductive performances and the bovine herpesvirus-1 (BoHV-1) infection being the notable one needs to be addressed (Sarkar et al. 2006). In India, the disease has high dimensions throughout the country and many reports of serological evidence of disease were made from cattle, buffalo, and small ruminants (Kiran et al. 2005; Nandi et al. 2007). Although BoHV-1 infection in yaks was first reported from China by Qu and Li (1988), a number of reports on BoHV-1 infections in cattle and buffaloes, very few reports are available on yak (Rahman et al. 2007), Mithun (Rajkhowa et al. 2004) and other wild animals such as wild buffaloes, elephant, and European bison (Rahman et al. 2007) from India. Materials and methods Location of the study area and serum samples Serum samples of all the yaks (188) from National Research Centre on Yak (NRCY), Dhirang, Arunanchal Pradesh were collected. It included 113 yak females and 75 yak males aged from 4 months to 11 years that were apparently healthy except the history of abortion in 20 animals and conjunctivitis in few animals. Vaccination against the disease is not practiced in India and no animal in this farm was vaccinated against BoHV-1. All the animals under study were reared under semi- intensive management and were allowed to graze and mix freely with other livestock. Besides providing sufficient green fodder, concentrate mixture (high energy and protein) was included in their daily ration and both natural mating as well as artificial insemination was practiced. The state Arunachal Pradesh is a thinly populated hilly tract on the easternmost part of India, surrounded on three sides by the international border with Bhutan to the west, China to the north, and Myanmar to the east. The mean temperature varies from -4 to +20°C with a S. Nandi (*) : M. Kumar Centre for Animal Disease Research and Diagnosis (CADRAD), Indian Veterinary Research Institute, Bareilly, Uttar Pradesh, India e-mail: snandi1901@yahoo.com Trop Anim Health Prod (2010) 42:1041–1042 DOI 10.1007/s11250-010-9526-1