Bovine mastitis, an inflammation of the mammary gland, is the most common disease of dairy cattle causing economic losses due to reduced yield and poor quality of milk. The etiological agents include a variety of gram-positive and gram-negative bacteria, and can be either contagious (e.g., Staphylococcus aureus, Streptococcus agalactiae, Mycoplasma spp.) or environmental (e.g., Escherichia coli, Enterococcus spp., coagulase-negative Staphylococcus, Streptococcus uberis). Improving sanitation such as enhanced milking hygiene, implementation of post-milking teat disinfection, maintenance of milking machines are general measures to prevent new cases of mastitis, but treatment of active mastitis infection is dependant mainly on antibiotics. However, the extensive use of antibiotics increased concerns about emergence of antibiotic-resistant pathogens and that led the dairy industries to reduce the use of antibiotics. Therefore, alternative therapies for prevention and treatment of bovine mastitis, particularly natural products from plants and animals, have been sought. This review provides an overview of bovine mastitis in the aspects of risk factors, control and treatments, and emerging therapeutic alternatives in the control of bovine mastitis.

Bovine mastitis: risk factors, therapeutic strategies, and alternative treatments - A review.

Farmers should focus on milk quality over quantity because milk that contains unsuitable components and/or antibiotic residues, or has a high somatic cell count, cannot be used in food production and thereby results in reduced milk yield. One of the main problems affecting the ultimate milk yield of dairy cows is mastitis. This disease is the most serious economic and health problem associated with dairy cow herds and is a major reason for excessive culling. Therefore, many studies have addressed this problem to further our understanding of the agents causing mastitis and their classification and virulence factors. This review summarizes the current knowledge regarding mastitis prevalence, the characteristics of its main causative agents, and the effects of mastitis on dairy production. The review also intends to provide guidance for future studies by examining external effects influencing dairy production in cows under field conditions.

https://www.mdpi.com/2076-2615/10/12/2212/pdf

Epidemiology and Classification of Mastitis

Stevens DL, Kaplan EL, eds. 449 pages. New York: Oxford Univ Pr; 2000. $98.50. ISBN 0195099214. Order phone 800-451-7556. Field of medicine: Infectious diseases, public health, microbiology, and epidemiology. Format: Hardcover book. Audience: Physicians in adult and pediatric infectious disease, public health officials, epidemiologists, and microbiologists. Purpose: To review the spectrum of clinical problems caused by streptococci and to define current understanding of the epidemiology, physiology, and pathophysiology of these microorganisms. Content: The book concentrates on the major clinically significant and pathogenic streptococci. Pathophysiologic concepts are reviewed from a molecular perspective. Forty percent of the book is devoted to group A streptococci, focusing on genetic and virulence factors and on the clinical features and pathogenesis of suppurative and nonsuppurative manifestations of infection. Chapters on groups B, C, and G and nonhemolytic streptococci highlight new understanding of the mechanisms of the diverse infections caused by these important pathogens. Enterococcal and pneumococcal infections are reviewed in the context of increasing antimicrobial resistance. Oral streptococci and the pathogenesis of local and extraoral disease caused by these organisms is discussed. Prevention of streptococcal infections with antibiotics and vaccines is addressed comprehensively, and current research in the development of group A and B streptococcal vaccines is reviewed. The many challenges that remain in the prevention of pneumococcal disease are discussed. Highlights: The distinguished group of international contributors make the book come alive with historical vignettes and first-hand experience. The introductory chapter, History of Hemolytic Streptococci, provides an outstanding perspective. Each chapter is copiously referenced with classic and new important articles. The chapter on oral streptococci and human disease highlights the fascinating oral microenvironment and its impact on human health. Limitations: Some chapters include relatively few illustrations, and only one page of color photographs is included. The chapters overlap somewhat, but generally this adds depth and interest to topic coverage. Related reading: No other current texts address streptococci and the diseases that they cause in comparable depth. Comprehensive infectious disease textbooks, such as Mandell and colleagues' Principles and Practice of Infectious Diseases (Churchill Livingstone, 2000), provide an excellent overview of streptococcal syndromes and pathogens. Reviewer: Nicholas J. Lekas, MD, Oakwood Hospital and Medical Center, Dearborn, Michigan.

Streptococcal Infections: Clinical Aspects, Microbiology, and Molecular Pathogenesis

Global and countrywide prevalence of subclinical and clinical mastitis in dairy cattle and buffaloes by systematic review and meta-analysis.

Brucellosis in Africa is caused by Brucella species transmitted through contaminated or contacts with infected animals or their carcasses. The disease reduces livestock production and reproduction performance evident by frequent episodes of abortion, still births, swollen testes, weak calves/lambs and swollen joints. However, the socio-economic impacts of these brucellosis-associated symptoms on milk, fat, meat and blood production, infertility, sale value, dowry and costs of treatment has not been evaluated extensively in developing countries. In Baringo County, Kenya, there is a continuous movement of cattle as a result of trade and grazing, which predisposes many herds to brucellosis infection. The objective of this study was to investigate the socio-economic impacts of Brucella infection on production systems for sheep, goats, cattle and camels and explore the impact of brucellosis on livestock production and reproduction performance among livestock keeping communities in Baringo County, Kenya. The study adopted a cross-sectional survey using quantitative data collection methods. Results demonstrated an impact on milk production in suspected brucellosis cases resulting from abortions (OR = 0.151, P < 0.0001) and swollen joints (OR = 2.881, P < 0.0001). In terms of infertility, abortion as a symptom of brucellosis (OR = 0.440, P = 0.002), still birth (OR = 0.628, P = 0.042), and weak calf or lamb (OR = 0.525, P = 0.005) had an impact on infertility. In terms of sale value, abortion (OR = 0.385, P = 0.008), weak calf/lamb (OR = 2.963, P = 0.013) had an impact on sale value. Other analyses demonstrated that for dowry, swollen testes (OR = 5.351, P = 0.032), weak calf and lambs (OR = 0.364, P = 0.019) had a likelihood of reduction of dowry value. Finally, in terms of cost of treatment, abortion (OR = 0.449, P = 0.001), still births (OR = 0.208, P = 0.015), swollen testes (OR = 0.78, P = 0.014), weak calf/lambs (OR = 0.178, P = 0.007) and swollen joints (OR = 0.217, P = 0.003) significantly increased the costs of treatments. There was no impact on fat and meat and blood production. Even though there was a huge socio-economic impact on milk production, infertility, sale value, and dowry, it was the costs of treatment that was significantly impacted on all symptoms associated with brucellosis on this community. A ‘One Health’ approach in tackling the brucellosis menace as a holistic approach is recommended for both humans and their livestock.

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Socio-economic impacts of brucellosis on livestock production and reproduction performance in Koibatek and Marigat regions, Baringo County, Kenya

A cross-sectional study was carried out to determine the prevalence and risk factors of bovine mastitis caused by Streptococcus agalactiae from farms in and around Haramaya district, eastern Ethiopia. A total of 384 lactating cows were selected from small-, medium-, and large-scale production systems. California mastitis test (CMT) was used for screening subclinical mastitis. Out of the total animals examined, 63.02% (n = 242) had mastitis, where 6.77% (n = 26) and 56.25% (n = 216) were clinical and subclinical mastitis respectively. The quarter-level prevalence was 29.04% (n = 446), from which the clinical form was 6.38% (n = 98) and the subclinical was 22.66% (n = 348), and the rest quarters were blind 3.32% (n = 51). Milk samples from clinical as well as CMT positive quarters were cultured for isolation of S. agalactiae, where 10.3% (n = 46) resulted in growth of the bacterium. The prevalence of mastitis was found to be statistically significant among the age groups (p = 0.002), breed (p = 0.000), and parity (p = 0.000). Similar findings were found to the extrinsic risk factors considered; as production type (p = 0.010), teat injury (p = 0.02), and type of floor (p = 0.000). The study confirmed the importance of S. agalactiae as the cause of contagious mastitis and also identified the associated risk factors in the study farms and hence warrants serious attention.

/pdf/risk-factors-for-bovine-mastitis-with-the-isolation-and-2u67j34r4p.pdf

Risk factors for bovine mastitis with the isolation and identification of Streptococcus agalactiae from farms in and around Haramaya district, eastern Ethiopia.

Mastitis is the inflammation of mammary gland which has economic importance all over the world. A cross sectional study was carried out from November 2014 to March 2015 to estimate the prevalence of mastitis caused by Streptococcus agalactiae and also assesses the associated risk factors in and around Haramaya District, Eastern Hararghe, Ethiopia. A total of 384 lactating cows from selected semi-intensive and intensively reared cows were included in the study. California mastitis test (CMT) was used for screening of the subclinical mastitis while the clinical type was identified by clinical examination of udder. Out of the total examined animals, 63.02% (n= 242) animals had mastitis, from which 6.77% (n=26) and 56.25% (n=216) were clinical and subclinical mastitis respectively. The quarter level prevalence was 29.04% (n=446); from which the clinical form was 6.38% (n=98) and the subclinical was 22.66% (n=348) where 3.32% (n=51) quarters were blind. Milk samples from clinical as well as CMT positive quarters were subjected to bacteriological culture for isolation of S. agalactiae of which 19.01% (n=46) resulted in growth of the bacterium. The prevalence of mastitis was found to be statistically significant among different age groups (p=0.002), breed (p=0.000) and parity (p=0.000) from intrinsic risk factors considered which was similar to the extrinsic risk factors considered; as production type (p=0.010), teat injury (p=0.02) and type of floor (p=0.000). In conclusion, this study confirms the importance of S. agalactiae as the cause of contagious mastitis and also identified the associated risk factors in the study farms and hence warrants serious attention.

Isolation and Identification of Streptococcus Agalactiae and Associated Risk Factors in Bovine Mastitis in and Around Haramaya District, Eastern Ethiopia (Dvm Thesis)

Taresa Fayera

Papers

Risk factors for bovine mastitis with the isolation and identification of Streptococcus agalactiae from farms in and around Haramaya district, eastern Ethiopia.

Isolation and Identification of Streptococcus Agalactiae and Associated Risk Factors in Bovine Mastitis in and Around Haramaya District, Eastern Ethiopia (Dvm Thesis)