Bovine Mastitis and Its Therapeutic Strategy Doing Antibiotic Sensitivity Test

Review Article

Austin J Vet Sci & Anim Husb. 2017; 4(1): 1030.

Bovine Mastitis and Its Therapeutic Strategy Doing Antibiotic Sensitivity Test

Hossain MK¹*, Paul S², Hossain MM³, Islam MR³ and Alam MGS4

¹Department of Surgery and Theriogenology, Sylhet Agricultural University, Bangladesh

²Department of Public Health and Epidemiology, Sylhet Agricultural University, Bangladesh

³Department of Medicine, Sylhet Agricultural University, Bangladesh

4Department of Surgery and Obstetrics, Bangladesh Agricultural University, Bangladesh

*Corresponding author: Hossain MK. Department of Surgery and Theriogenology, Faculty of Veterinary and Animal Science, Sylhet Agricultural University, Tilagor, Sylhet-3100 Bangladesh

Received: November 23, 2016; Accepted: March 02, 2017; Published: March 10, 2017

Abstract

Mastitis is one of the most costly devastating diseases in the dairy industry. Bovine mastitis can be classified as clinical or subclinical based on clinical features of the disease. Subclinical mastitis occurrence is more prominent compared to clinical form and its prevalence is more than 20 to 50% of cows in given herds. Both forms cause substantial financial losses due to reduced milk yield, degraded milk quality, drug costs and veterinary expenses, early culling of cows and increased labour costs for the farmers. The chief causal organisms of mastitis are cell-walled bacteria, even though mycoplasma, algae and yeast have also been identified to cause mastitis. Numerous influencing factors like physiological, pathological, environmental or genetic factors may contribute to the occurrence of mastitis in dairy cattle. Presently, different types of antibiotics are prescribed for the treatment of mastitis. However, therapeutic success rate of mastitis is generally poor because of pathological changes in the udder parenchyma, mastitogenic bacterial and related factors, indiscriminate use of antibiotics and poor animal husbandry practices. These evidences focus the necessity for discovering completely newer strategies for treatment of mastitis. This review will highlight the key etiological agents and factors affecting the manifestation of mastitis, and the recent advancement of therapeutic strategies including application of antibiotic-based therapies by doing antibiotic sensitivity test as a prospective approach to prevent and control mastitis in dairy herds.

Keywords: Mastitis; Causal agents; Factors; Antibiotics; Sensitivity test

Abbreviations

MIC: Minimum Inhibitory Concentration; SCC: Somatic Cell Count; CMT: California Mastitis Test; kPa: Kilo Pascal; NAGase: N-acetyl-β-D-glucosaminidase; LDH: Lactate Dehydrogenase Activity; EC: Electric Conductivity; MBC: Minimum Bactericidal Concentration, IL: Interleukins; TNF-a: Tumor Necrosis Factor alpha

Introduction

Mastitis is one of the important devastating diseases in cattle striking the greatest challenge to the dairy industry [1,2]. Mastitis remains the most economically destructive and zoonotic imminent disease for consumers irrespective of many years of research worldwide with different levels of economic losses identified by different countries [2-6]. Milk production is reduced considerably in the affected animals and estimated loss of milk yield may range from 100 to 500 kg per cow per lactation [7]. The predictable loss causing clinical mastitis in cows is nearly 700kg in first lactation and 1,200kg in the second lactation [8]. In United States, expenses related to mastitis on dairy farms are around U$ 200 per cow per year and an estimated annual loss of 2 billion dollars for dairy industry [9]. Australian dairy industry is losing more than $130 million every year because of poor udder health causing reduced milk production that is mainly associated with mastitis [10]. In India, annual economic loss suffered by dairy industry owing to udder infections is estimated to be more than $120 million [2,11]. Economic consequences of mastitis, clinical or sub-clinical, include reduced milk yield, poorer quality milk, increased culling rate, increased cost of veterinary services and medicine and increase labor cost for the farmers [12-15]. Bacterial contaminated milk from mastitis infected cows can impede with food manufacturing process or can cause food poisoning; may render unsuited for human consumption, and in some circumstances may have the possibility to transmit disease to humans [16].

Medical therapy involving antibiotics is a key tool in the scheme of mastitis treatment and control. For successful antibacterial mastitis therapy, the active medicine must achieve and conserve concentrations above the minimum inhibitory concentration (MIC) at the center of infection for long enough to breakdown the production and toxin-producing phase of the causal pathogen [17-18]. This may be prohibited by several factors that include pathological changes in the udder parenchyma, mastitogenic bacterial and related factors, poor selection and indiscriminate use of antibiotics, and is also influenced by the route of administration [16]. Enormous economic losses by mastitis are also experienced due to unmarketable milk or milk-products adulterated with antibiotic residues originating from treatment in the developing nations along with usage of antibiotics as growth promoters predominantly in dairy feedlots in the advanced world [20-21]. The long time use of antibiotics in the treatment of mastitis has directed further problem of occurrence of antibiotic resistant strains, therefore there is continual worry about treatment failure and the resistant strains entering the food chain [22-24]. Treatment failures also lead to longer periods of infectivity, which increase the numbers of infected cows moving in the farm and thus expose the whole herd to the risk of contracting a resistant strain of infection. Continual attention has given by the researchers to discover the proper antibiotic to treat and control mastitis doing antibiotic sensitivity test. Therefore, this review will summarize the key etiological agents and factors affecting the manifestation of mastitis, and the recent status of therapeutic strategy including antibioticbased therapies by doing antibiotic sensitivity test as a prospective approach to prevent and control mastitis in dairy herds.

Mastitis Pathogens

Huge quantities of microorganisms have been known to cause bovine mastitis. The major causal microorganisms are bacteria, but mycoplasma, fungi and algae have also been reported to cause mastitis problems in some herds or regions [25-28]. It is very much interesting, about 137 species and subspecies of possible pathogens can be accompanying with infection of the mammary gland [29]. The proportionate importance of the pathogens has varied between countries, regions and farms, mostly owing to differences in management and housing systems [30]. Conversely, mastitis in dairy herds is commonly of two types, these are environmental mastitis and contagious mastitis (Table 1).