Identification of Pseudocowpox Virus in Angus Bull with Failure to Breed

Research Article

Austin Virol and Retrovirology. 2014;1(1): 5.

Identification of Pseudocowpox Virus in Angus Bull with Failure to Breed

Wendy Black1, Michael T Walburger3, Rocky Baker1, Claire Ostertag-Hill1, Aimee Reed2, Margo Whipple1 and Ling Jin1,2*

1Department of Biomedical Sciences, Oregon State University, US

2Department of Microbiology, Oregon State University, US

3Rocky Mountain Large Animal Clinic, US

*Corresponding author: Ling Jin, Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA

Received: July 25, 2014; Accepted: August 19, 2014; Published: August 21, 2014


Pseudocowpox, a Parapoxvirus, causes a common mild infection of the udder and teats of cows. Infection of genital organs has not been reported before in bulls. In this report, pseudocowpox virus (PCPV) was identified from one of two 1-year-old Angus bulls (Bos taurus) with red rashes and papule lesions on the surface of the penis. Inoculation of bovine turbinate cells or primary bovine testicular cells with the swab of the papule lesions produced CPE characteristic of pox virus infection. Parapoxvirus like particles were observed by EM in viral pellets of the tissue culture isolate. To confirm the virus, designated 14V10296 isolate, was a Parapoxvirus, viral DNA of the 14V10296 isolate was examined by PCR with pan Parapoxvirus primer sets that could amplify B2L gene of all four Parapoxviruses. The expected B2L amplicons of the 14V10296 isolate showed 99% homology to B2L of PCPV strain F00.120R. To further confirm the isolated virus is PCPV, PCR primers specific for Orf vascular endothelial growth factor gene and IL-10 and PCPV uracil DNA glycosidase (UDG) and IL-10, respectively, were used to amplify the viral DNA of the 14V10296 isolate. Only when PCR primers specific to PCPV UDG and IL-10 were used, expected products were amplified from viral DNA of the 14V10296 isolate, respectively. Phylogenetic analysis suggests the 14V10296 isolate is closely related to PCPV strain F00.120R, an isolate from reindeer. These results from tissue culture, EM, PCR amplification and DNA sequence analysis suggest that the bulls were infected by a PCPV which is closely related to PCPV strain F00.120R.

Keywords: Pseudocowpox; Parapoxvirus; Angus bull


Pseudocowpox virus causes a common, mild infection of the udder and teats of cows. This virus is widespread worldwide. Pseudocowpox virus (PCPV) is a member of genus Parapoxvirus in the family Poxviridae, which includes bovine popular stomatitis virus (BPSV), contagious ecthyma virus (Orf) in sheep and goats, and Parapoxvirus of red deer [1]. These Parapoxviruses differ morphologically from other poxviruses of other genera. Lesions from Parapoxvirus infections normally begin as small, red papules on the teats or udder and are followed rapidly by scabbing or by the formation of small vesicles [2,3]. Infection of PCPV is self-limiting and normally resolves in about 2 weeks; however, some lesions may persist for several months, giving the affected teats a rough feel and appearance and more scabs may form. The infection spreads slowly throughout milking herds and a variable percentage of cows show lesions at any one time. Cattle may become re-infected in subsequent lactations. Infection of PCPV is mostly associated with the udder and teats [4]. Infection of genital tissue has not been reported in cattle. This study describes a PCPV, 14V10296 isolate that was isolated from a bull with failure to breed.

Materials and Methods

Case presentation

Two 1-year old Angus bulls were purchased from a pure bred breeder in Idaho. They were ranch raised, weaned and finished in allotments of 100-400 individuals. When exposed to cows, both bulls exhibited difficulty with intromission. They failed to breed in the spring of 2014 and were examined at Rocky Mountain Large Animal Clinic in Spanish Fork, UT. Poxvirus like lesions were seen on the prepuce and penis of bulls as red rashes (Figure 1C), papules, and vesicles (Figure 1A,1B). A preputial swab from one bull and preputial scraping from another bull were collected and sent to the Oregon State University Veterinary Diagnostic Lab for virus isolation.