INVESTIGATION OF BACTERIAL PATHOGENS AND ASSOCIATED RISK FACTORS FOR SUBCLINICAL MASTITIS IN GOATS AT CHITTAGONG IN BANGLADESH

Abstract

Goat plays a considerable role in economy and major part of subsidiary income of the rural people in Bangladesh. Interest in dairy goats and goat milk products is increasing with the demand for healthy food, as goat milk has similar nutritional qualities to human milk and is less allergenic for human consumption than cow milk. This importance is also reflected by increase in goat’s population during the last 20 years in Bangladesh. Therefore, any factor that adversely affects the quantity and quality of milk from the goat is of great financial interest. Milk quality is mainly affected by bacterial infection of the mammary gland which causes mastitis. Dairy animals including lactating goats are prone to the intramammary infection and associated with a lot of economic impact on the farmers but the scientific reports on caprine subclinical mastitis are limited in Bangladesh.

The present study was undertaken to determine the proportionate prevalence of subclinical mastitis at farm and goat level along with the potential risk factors associated with subclinical mastitis and mastitis related organisms during the period from October 2015 to December 2016 at Chittagong metropolitan city. The teat and udder of a lactating population of 106 goats from 88 goat farms were physically examined.

Most of the goats were reared under intensive as well as semi-intensive rearing system and rests were at free range system. Wooden floor was more common floor type among the studied farm and others were constructed with concrete and brick and some were found only plastic and jute bag over mud. Goat farmers had got predominantly the secondary level of education.

In this study the proportionate prevalence of subclinical mastitis at goat level was 50% whereas; the quarter level proportionate prevalence was 46.2%. The major bacterial pathogens isolated were coagulase-negative staphylococci (35.4%); (95% CI: 28.9-42.2%) followed by Pseudumonas spp (23.1%); (95% CI: 17.6-29.4%), Staphylococcus aureus (11.3%); (95% CI: 7.4-16.4%), and other organisms (8.9%).

Fisher’s exact test followed by Generalized Estimating Equation was applied to identify potential risk factors associated with SCM in goat. Source of goat (OR=2.2: Own stock versus external), Floor materials (OR=3.7: Concrete and brick; Wood versus Plastic and jute bag), Parity (OR=2.0: First and second versus Third to fifteenth), Teat shape (OR=3.6: Bottle and collapsed; Pencil and short versus Conical and cylindrical) and Lactation period (OR=5.3: Up to 60 versus 61 to 180) were identified as the risk factors for SCM in goat. Knowledge obtained from the study could help in practicing hygienic management system for goat farming to reduce SCM in goat.