ABSTRACT
The external morphological traits of the mammary gland, and their relationships with somatic cell count (SCC) and the presence of intramammary infection (IMI), were studied in 30 Serrana goats, Transmontano ecotype. Globular-shaped udders were the most predominant, with slightly separated and symmetrical halves, presenting some degree of suspension. Funnel-shaped teats were the most prevalent shape with an opening of 120° to 160° degrees. Significant differences were observed between healthy group and the coagulase negative staphylococci (CNS)-infected group for udder cleft, teat perimeter and distance between teats parameters; and between healthy group and CNS or Staphylococcus aureus groups for degree of separation, teat shape and udder shape (p < 0.05). The udder shape, symmetry, degree of suspension and degree of separation parameters showed to be different depending on SCC (p < 0.05). The udder perimeter and udder depth traits showed differences between the lowest and the middle SCC group. We concluded that bifurcated pendular udders, with vertical loose teats and located close to each other, are more likely to have IMI, and have the highest SCC. The inclusion in breeding programs of certain mammary conformation traits would not only help to improve milk production, but would also decrease the susceptibility to IMI of the herd.
ABSTRACT
Several reproductive factors may affect milk yield in goats. The main aim of this study was to evaluate the influence of reproductive disorders, parity, and litter size, and their interactions on the 150-day standardized milk yield (SMY150) of low-producing dairy goats extensively raised. A total of 148,084 lactations between 1993 and 2015 were obtained from data of the Genpro pedigree records of the Transmontano ecotype of Serrana goat breed. The presence or absence of reproductive disorders (RD) from late (>half) pregnancy (abortions followed by lactation) or at kidding, number of fetuses (single vs. multiple), and parity (primiparous vs. multiparous) of the Transmontano ecotype of Serrana goat were used as fixed effects to fit a general linear model for a SMY150 output. A significant effect (p < 0.001) of all factors on SMY150, as well as three-way interactions, were observed. The SMY150 reduction subsequent to RD was 3.7% for multiparous and 9.6% for primiparous goats carrying singletons, and 14.1% for multiparous and 18.8% primiparous goats carrying multiple fetuses. It was concluded that a new lactation following abortion occurrence is viable for production purpose in low-producing dairy goats under pastoralism. Nevertheless, the impact of RD on SMY150 varied according to the number of fetuses and the parity of the Transmontano ecotype of Serrana goats. This information should be used in decision-making practices regarding reproductive and herd health management.
