Effect of Lippia alba hay as phytogenic feed additive on the lactation performance, milk composition, and rumen and blood parameters of Alpine goats

The objective of the study was to evaluate the intake, rumen and hematological parameters, milk composition and milk yield of dairy goats fed diets containing Lippia alba hay as phytogenic feed additive. Eight multiparous crossbred Alpine goats, at an average lactation stage of 50 +/- 4.5 days after kidding were used, distributed in a double Latin square design with four treatments [Lippia alba hay as phytogenic feed additive included at levels 0, 30, 60, and 90 g/kg of total dry matter (DM)]. Lippia alba inclusion linearly increased (P < 0.05) the daily intake of DM and acid detergent fiber, milk yield (MY), corrected MY3.5%, corrected-solids, and milk contents (g/d) of protein, fat, total solids, and defatted dry extract daily yield, feed efficiency (MY/DMI ratio) and MY/CP (crude protein) intake ratio of the dairy goats. In contrast, the intake of NFC, NDFap and total carbohydrates reduced (P < 0.001) due to Lippia alba hay as phytogenic feed additive in the goats' diet. The inclusion of Lippia alba as phytogenic feed additive in the diet of the dairy goats did not affect (P > 0.05) the CP, ether extract and crude ash intake, goat milk concentrations (%) of protein, fat, total solids and defatted dry extract, as well as cryoscopic index, pH, density and acidity of milk, red blood cells count, leukocytes count, packed cell volume, total plasmatic proteins, and rumen values of temperature (degrees C), pH, and methylene blue reduction, flotation/sedimentation time, color, and consistency of goat rumen fluid. However, the inclusion of Lippia alba hay as a microbial additive reduced moderate (++) and increased abundant (+++) protozoa motility and reduced the density of medium size protozoa, and increased large size protozoa count (P < 0.05). The addition of moderate amounts (up to the level of 90 g/kg total diet) of Lippia alba hay as a phytogenic feed additive in the diet of dairy goats is recommended because it has favorable effects on intake, milk yield, and solids content, with no negative effects on rumen and hematological parameters.