Abstract

ZUMBO, A. et al. Quantitative and qualitative milk characteristics of Nebrodi goats. S. Afr. j. anim. sci. [online]. 2004, vol.34, n.5, pp.155-157. ISSN 2221-4062.

Milk quantity and quality characteristics were investigated in 40 lactating Nebrodi goats of different ages and order of kidding. Every month from the start of the first lactation individual daily yields were recorded and individual milk samples were taken to determine the concentrations of fat, protein and lactose, the somatic cell count (SCC), pH, titration acidity (°SH) and clotting properties, using the parameters r (clotting time), k₂₀ (curd firming time) and a₃₀ (curd firmness). Results show that the daily milk yield was higher for the goats in the third and higher parity, while the protein and fat levels were higher in the primiparous goats. Goats with multiple kids showed significant higher daily milk yield (942 g vs. 761g), lactose percentage (4.63 vs. 4.73) and SCC (log₁₀ 5.86 vs. log₁₀ 5.63) than does with single kids. The elastometric parameters of the milk from primiparous goats showed higher "r" and " a₃₀" values than older goats. The clotting time and curd firmness of the milk from goats that had multiple kids were higher than from goats with single kids. Pearson's analysis showed a negative correlation between daily milk production and fat and protein percentages (r = -0.235 and r = -0.179, respectively). A negative correlation between curd firmness (a30) and somatic cell content was observed, but the latter was correlated positively with clotting time, confirming the negative role of these cells on the milk clotting properties.

Keywords : Autochthonous populations; goat; milk quality.

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