Cashew (Anacardium occidentale L.) nut meal could be a promising alternative protein feedstuff for lambs

Abstract

In today’s livestock landscape, amid shortages and fluctuating feed commodity prices, quest for exploring under-utilised and possibly economical agro-industrial by-products remains key for sustainable farming. In this backdrop, notwithstanding the moderate energy and protein values of cashew nut meal (CNM)—a by-product of the cashew nut processing industry—there appears limited research exploration on it as a prospective feedstuff for lambs. Therefore, the present study was conducted to delineate the effect of inclusion of graded levels of CNM on intake, nutrient digestibility, growth performance, rumen fermentation, and economics in lambs fed Napier Pakchong-1 grass hay-based diet. For this, 24 Mandya ram lambs were divided into four similar experimental groups of six animals each in a completely randomised design based on a comparable body weight (7.9 ± 0.65 kg) and age (3–4 months). The treatments involved four isonitrogenous concentrate feed mixtures (CFM) with CNM included at 0 (T0), 100 (T1), 200 (T2), and 300 g/kg (T3), proportionally replacing soya bean meal and wheat bran. The results of the feeding trial spanning 120 days indicated that CNM had no effect on intake (except ether extract) and digestibility of nutrients, nutritive value of diets, and nutrient selection index among the four groups. The same trend was true for final body weight, average daily gain, and feed conversion (feed-to-gain) ratio. Furthermore, there were no significant (P > 0.05) differences in rumen fermentation pattern, including rumen pH, various nitrogen fractions as well as total- and individual volatile fatty acids among the experimental groups. Similarly, blood biochemistry was also unaffected by the inclusion of CNM in the diet. Beneficially, the use of CNM reduced the overall feed cost for growth to the extent of 5.1 % in group T3 than T0, indicating a modest economic advantage. Overall, CNM presents a promising alternative to conventional protein sources like SBM when included up to 300 g/kg CFM, offering comparable nutrient values without causing any discernible negative influence on key performance metrics and health.