Guar meal as an alternative protein source: effects on digestibility and growth performance of Nagavali ram lambs

This study evaluates the effect of varying levels of guar meal by substituting soybean meal on the digestibility and growth performance of Nagavali ram lambs. Twenty-four Nagavali ram lambs (average body weight 6-9 kg and 3-6 m age) were divided into four groups and assigned to four feeding regimens: (T1 to T4). The diets contained varying percentages of Guar meal viz., 50% (T2), 75% (T3) and 100% (T4). The effects of these diets on growth performance, were evaluated using a completely randomized design. The inclusion of Guar meal significantly (P < 0.05) improved total body weight gain and average daily gains in the T2, T3 and T4 groups along with non-significant(P > 0.05) improvement in dry mater intake in guar meal fed sheep. The observed dry matter intake of different treatments was 0.40 to 0.43 kg. Gross nutrients and cell wall digestibility parameters were not affected (P > 0.05). However, crude protein (CP) digestibility improved significantly (P < 0.05) with guar meal inclusion up to 75% (T3), after which a slight decline was noted at the 100% replacement level (T4). The invested cost per kg gain of body weight were $1.76, $1.69, $1.62 and $1.66 at T1 (0%), T2 (50%), T3 (75%) and T4 (100%) substitution levels, respectively, in line with FCR trends, demonstrating that T3 has the better results with comparatively low cost per kg gain. The study concludes that substituting soybean meal with 75% (T3) guar meal would enhance growth performance and aid in developing cost-effective rations.