INFLUENCE OF BETAINE ON GOAT MILK YIELD AND BLOOD METABOLITES

Abstract

Betaine is a natural occurring compound with methyl donor properties which is increasingly being used in animal feeding. Betaine, an oxidative product of choline is able to replace methionine in some physiologically important body processes. The subject of this work was to study the effect of betaine added to the diet on milk production and blood metabolites on Murciano-Granadina dairy goats.  Sixty lactating goats were selected from a commercial Murciano-Granadina goat herd (EXCAMUR S.L.) located in Murcia Region (Spain). Goats were selected from a 250 goats herd, taken  into account the age, stage of lactation (2.5 as average), live weight (36 kg as average) and type of birth (2 kids). Two homogenous groups of 30 goats were made and fed with 1.5 kg of compound feed and 1 kg of alfalfa hay per day and goat. Goats were fed twice a day and water was provided ad libitum. Both groups received the same diet but for the second group the diet was supplemented with 4 g∙kg-1 betaine (betaine anhydrous, Danisco Animal Nutrition). The feeds, presented in pellets, were formulated in based on recommendations of INRA (2007). The experimental period was 6 months and the experimental diets were provided 15 days before parturition. The herd was machine milked once at day. Chemical composition, milk production and blood metabolites of each goat were recorded and analyzed at the end of the trial. Variance analysis and means comparison were carried out using the general lineal model procedure and Tukey test for mean comparison. Goats fed with betaine diet had higher milk fat than goats fed control diet (4.8 vs. 5.2 % for control and betaine respectively; P<0.05). No significant differences were found for milk production (1.8 kg d-1 as average). Within blood metabolites, significant differences were found for the level of triglycerides, goats feeding with betaine were lower triglycerides level (0.76 vs. 0.48 mmol/l for control and betaine respectively; P<0.05). Further studies are necessary to understand the mechanism of action of betaine on physical-chemical characteristics of milk.