%0 Journal Article
%T The Immunology of Mammary Gland of Dairy Ruminants between Healthy and Inflammatory Conditions
%A Mohamed Ezzat Alnakip
%A Marcos Quintela-Baluja
%A Karola B£¿hme
%A Inmaculada Fern¨¢ndez-No
%A Sonia Caama£¿o-Antelo
%A Pillar Calo-Mata
%A Jorge Barros-Vel¨¢zquez
%J Journal of Veterinary Medicine
%D 2014
%R 10.1155/2014/659801
%X The health of dairy animals, particularly the milk-producing mammary glands, is essential to the dairy industry because of the crucial hygienic and economic aspects of ensuring production of high quality milk. Due to its high prevalence, mastitis is considered the most important threat to dairy industry, due to its impacts on animal health and milk production and thus on economic benefits. The MG is protected by several defence mechanisms that prevent microbial penetration and surveillance. However, several factors can attenuate the host immune response (IR), and the possession of various virulence and resistance factors by different mastitis-causing microorganisms greatly limits immune defences and promotes establishment of intramammary infections (IMIs). A comprehensive understanding of MG immunity in both healthy and inflammatory conditions will be an important key to understand the nature of IMIs caused by specific pathogens and greatly contributes to the development of effective control methods and appropriate detection techniques. Consequently, this review aims to provide a detailed overview of antimicrobial defences in the MG under healthy and inflammatory conditions. In this sense, we will focus on pathogen-dependent variations in IRs mounted by the host during IMI and discuss the potential ramifications of these variations. 1. Introduction The udder is the milk-producing organ of dairy animals; hence, for optimal production, it should be healthy. Mastitis is the inflammatory response of the mammary gland (MG) tissue to physiological and metabolic changes, traumas, and allergies and, most frequently, to injuries caused by various microorganisms. Mastitis is considered the utmost threat to the dairy industry from three perspectives: economic, hygienic, and legal (EU Directive 46/92, modified by Directive 71/94). The intramammary inflammation (IMI), accompanied by immunological and pathological changes in the MG tissue, occurs at different degrees of intensities and results in a wide range of consequences regarding physical, chemical, and often microbiological alterations of secreted milk. A wide spectrum of microorganisms, including fungi, yeast, algae, Chlamydia, and viruses, have been incriminated in causing mastitis, but bacteria remain the principle causative agents of such complex [1, 2]. The major bacterial mastitis pathogens (Staphylococcus aureus, Streptococcus agalactiae, S. uberis, S. dysgalactiae, and coliforms) are most often responsible for clinical mastitis (CM). Meanwhile, minor pathogens (coagulase-negative staphylococci ¡°CNS¡±;
%U http://www.hindawi.com/journals/jvm/2014/659801/