Mastitis represents one major constraint in dairy goat farms implicating adverse effects on milk yield and composition and, in some cases, public health constraints. Intramammary infection, the principal cause of mastitis, can reach high prevalence in dairy goat herds, commonly more than 30%. Coagulase-negative staphylococci and coagulase-positive staphylococci, with emphasis for Staphylococcus aureus, are the major bacterial species related with in intramammary infection. Milk pathogens overtake anatomical, physiological, and immunological local defenses of the mammary glands. However, some enzootic systemic disease, such as contagious agalaxia, among others, with systemic tropism for the mammary gland, can have a significant impact on the milk production and quality. At immune level, neutrophils play a major role in the healthy and infected mammary gland representing 45–75% of total leucocyte counts in milk. Apparently, the threshold for significant neutrophils increase is 700,000 cells/ml. Moreover, the continuous renewal of epithelial cells from apocrine glands, which have phagocytosis cytokine production properties, improves significantly the somatic cells in milk. All these topics are discussed in the present chapter providing key points to improve the udder health status in goats.
