Preliminary effects of microseaweed addition in the diet on goat immune status.

Abstract

10 Majorera dairy goats were randomly assigned into two experimental groups according to the diet. Control group (CG) received corn, soy 66, dehydrated Lucerne, and dehydrated beetroot, wheat straw and a vitamin–mineral corrector according to the guidelines of L’Institute National de la Recherche Agronomique. The microseaweed group (MG) was fed with the same diet than CG plus 5 g/day of Chlorella pyrenoidosa. This procedure was used from 15 days before the expected parturition date to 40 days after partum. A blood sample of each goat was obtained immediately before the first treatment and onwards, 1 week after, at partum, 5, 10, 20, 30 and 40 days of lactation. After centrifuged, blood plasma was storage at -80°C until analysis was performed. Milk samples were obtained at partum, 1, 2, 3, 4, 5, 10, 20, 30 and 40 days of lactation and frozen at -80°C until analysis. IgG concentration and the Chitotriosidase activity (ChT) were measured in blood and milk samples by using a commercial ELISA goat kit and fluorimetric assay. No significant differences for blood plasma IgG concentration and ChT activity were observed between groups during the experiment. Blood plasma IgG concentration peaked at day 20 in both groups (17.4 and 17.0 mg/mL, CG and MG respectively) but showed a slightly increase earlier (5 d postpartum) in MG than in CG (10 d). Blood plasma ChT activity ranged from 4896.1 to 5673.5 nmol/mL/hour in CG and from 4362.6 and 5456.4 nmol/mL/hour in MS group. At day 40 after microseaweed inclusion ChT activity was significantly higher than before treatment. A time effect on colostrum IgG concentration was observed in both groups; the highest values were observed at partum (39.3 and 30.1 mg /mL in CG and MG respectively) decreasing along the time. Milk ChT activity peaked at partum in both groups (9253.2 and 10392.0 nmol/mL/hour for CG and MG respectively). These preliminary results suggest that the addition of 5 g of Chlorella pyrenoidosa to the diet could have an effect on the goat immune status; however the concentration of microseaweed added should be revised.