Mastitis is a common disease of cattle, buffaloes, dairy and non-dairy goats associated
with the inflammation of mammary parenchyma, protracted production loss, risks of premature
culling from the herd and the release of injurious toxins in the udder. IMIs in dairy goats can
cause economic losses due to decreased milk production as well as risks to public health and
discarded milk.
A total of one hundred goats affected with mastitis were included in this study. Samples
were collected from the abattoirs of Lahore. Mastitis was diagnosed on the basis of visible and
palpable changes in udder and milk. Pre-slaughter and post slaughter examination of udder was
performed and gross lesions were observed. Samples included udder parenchyma and
supramammary lymph nodes from mastitis affected goats. Each sample was divided into two
parts, one part was placed in small polyethene bag in an ice box under aseptic conditions for
bacteriological examination and second part was fixed in 10% neutral buffered formalin solution
for histopathological evaluation. Samples were cultured for identification of staphylococci,
streptococci and E.coli on Staph 110, Blood agar and MacConkey’s agar respectively.
Biochemical tests were also performed for confirmation of these bacteria. Confirmation was
made on the pattern of reactivity of bacterial cultures to biochemical tests.
Bacteriological investigation demonstrated the different species of bacteria involved
commonly in caprine mastitis. Staphylococcus aureus was isolated from 21 cases, CNS from 10
cases, Streptococcus spp. from 7 cases and E.coli from 3 cases as single infection and 25 cases of
mixed infection were observed in different combination of these bacteria. Results of the study
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revealed that Staphylococcus aureus is associated with statistically significant changes in udder
parenchyma as well as in supramammary lymph nodes. Marked changes have been observed in
case of tissue necrosis, exudation and gangrene. Moreover, tissue responses to mononuclear cell
infiltration have also been observed significant in Staphylococcus aureus infection. CNS,
Streptococci and E. coli revealed relatively comparable changes in tissue with slight variability.
However, mixed infection of these bacteria in a single tissue led to relatively much pronounced
histopathological changes as compared to the solitary infections. This could be attributed to the
synergistic effects of various bacterial activities, enzymes, toxins and host responses to more
than one type to bacteria.