A Study on the Epidemiology of Bovine Brucellosis in Punjab (India) Using Milk-ELISA

Aulakh H. K., P. K. Patil, S. Sharma, H. Kumar, V. Mahajan, K. S. Sandhu: A Study on the Epidemiology of Bovine Brucellosis in Punjab (India) Using Milk-ELISA. Acta Vet. Brno 2008, 77:393-399. Bovine brucellosis, caused by Brucella abortus, is a serious zoonotic disease manifested by reproductive disorders resulting in huge economic losses to dairy farmers. A random survey was conducted to study the epidemiology of brucellosis in Punjab (India) using sampling software Survey Toolbox. Two-stage sampling procedure was adopted; in the first step, villages were selected randomly from sampling frame of all the villages of Punjab followed by selection of owners, and animals in individual farms were identified using random sampling. In all, 32 villages were selected and then 345 animals (approximately 5%) were sampled from these villages. The milk samples collected were screened for brucella antibodies employing ELISA test. The overall apparent prevalence of brucellosis was found to be 18.26% (true prevalence 17.68%). The prevalence in the central zone of the state was significantly higher, viz. 23.2% (chi square = 11.34, p < 0.01) compared to 14.2% in the sub-mountainous zone and 5.8% in the arid irrigated zone. The disease prevalence was found to be non-significantly higher (chi square 1.029, p = 0.310) in cattle (20.67%) compared to buffaloes (16.41%) and increased with age (chi square = 8.572, p < 0.05) in both species. There was significant association between disease and abortion (chi square = 22.322, p < 0.01) and maximum abortion cases due to brucellosis were found in > 6 month of gestation (95.7%). The disease was significantly associated with the retention of placenta (chi square = 8.477, p < 0.01), however there was no significant relationship of the disease with repeat breeding (chi square = 0.044, p = 0.834). The results of the study suggested that the accurate epidemiological scenario of the disease may be obtained by employing multistage sampling procedures using milk-based ELISA. Cattle, buffaloes, brucellosis, epidemiology, milk ELISA Bovine brucellosis, caused by Brucella abortus, is a serious zoonotic disease manifested by reproductive disorders such as abortions, infertility, retention of placenta, stillbirth and calf loss in animals, and results in huge economic losses to dairy farmers (Radostits et al. 2000; Singh et al. 2002). Various studies have been conducted in India to establish the prevalence of the disease in bovines (Sandhu et al. 2001; Singh et al. 2004ab; Sharma et al. 2007) but these studies were based mainly on non-random sampling techniques. Hence the information gathered from such surveys cannot be extrapolated to apply to state or national bovine populations. Moreover, these studies were based on detection of antibodies in serum using conventional serological tests. The milk ring test is probably the most widely used test for the screening and monitoring of brucellosis in dairy cattle (Alton et al. 1988), but its sensitivity and specificity is questionable (Huber and Nicoletti 1986). In the last decade, several indirect enzymelinked immunosorbent assays (ELISA) have been developed and successfully tested on milk samples (Romero et al. 1995; Vanzini et al. 2001). The present study was designed to assess the epidemiology of the disease in the bovines of Punjab (India) using milk ELISA employing a multistage sampling procedure. Address for correspondence: P. K. Patil Department of Epidemiology and Preventive Veterinary Medicine College of Veterinary Science, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana 141004 India Tel: 91-161-2414030 (work) Fax: 91-161-2400822 E-mail: [email protected] http://www.vfu.cz/acta-vet/actavet.htm ACTA VET. BRNO 2008, 77: 393–399; doi:10.2754/avb200877030393