Relationship between body condition score, metabolic profile, milk yield and milk composition in goats browsing a Mediterranean shrubland

A study has been carried out in the centre-east area of Corsica (altitude 850 m a. s. l.) in three goat herds (Corsican local breed) browsing a Mediterranean shrubland without any additional feed supply. The practical usefulness of BCS and metabolic profile in order to assess the nutritional conditions of goats during the milking period (80 to 120 days of lactation) was investigated on a sample of 18 goats selected in each herd. BCS, metabolic profile, and milk yield/quality were individually measured. A negative overall correlation was found between the mean BCS and milk yield (r = -0.24, P < 0.05), due to the opposite trend of milk production and fat deposition. In the herd with highest average milk yield, lower blood urea (P < 0.05), in early and mid lactation, and higher milk protein content (NS, P > 0.05) were found. Blood P and Mg values indicate a sufficient intake of these minerals. Our results indicate that, under the specific conditions of this study, goats browsing a Mediterranean shrubland can produce a fairly good quantity of milk with good composition, without a significant depletion of fat reserves or marked metabolic imbalances. Under extensive husbandry conditions, BCS and to a lesser extent blood parameters, can help in explaining the differences in milk yield between goat herds. (C) 1999 Elsevier Science B.V. All rights reserved.