Milk production of dairy goats fed diets with different legume seeds: Effects of amino acid composition of the rumen undegradable protein fraction

Abstract

BACKGROUND: To establish the effect of the nature of four different legume seeds, lupins (L), faba beans (FB), bitter vetch (BV) and vetch (V) on the production and composition of goat milk, we studied the ruminal degradation of these legumes, and the amino acid (AA) composition of the seeds and that of the undegradable fractions of the protein sources. Four isonitrogenous and isoenergetic diets were designed, and in each case 30% of the protein was supplied by one of the different legume seeds. A group of eight Granadina goats was used to study the utilisation of these diets for milk production. The goats were allocated to a replicated 4 × 4 Latin square.

Legume grain-based supplements in dairy sheep diet: effects on milk yield, composition and fatty acid profile

“…In general, the use of various legume seeds to replace soybean protein of the concentrate does not affect milk production of small ruminants, as demonstrated with chickpea (Christodoulou et al 2005), faba bean (Liponi et al 2007;Ramos Morales et al 2008), and pea (Bonomi et al 2003;Liponi et al 2007;Renna et al 2012). In particular, there have been a very limited number of studies on the impact of legume seeds on the milk FA profile.…”

ORIGINAL ARTICLE: Nitrogen and energy utilization in lactating dairy goats fed diets with different legume seeds

“…However, it should be taken into account that corn presents a level of protein (7.44%) that is considerably lower than that of barley (11.25%). In consequence, the effective degradability values of the protein in all four diets were fairly similar, although that corresponding to the lupin diet was a little lower (ED dietary protein: L = 76%, FB = 81%, BV = 82% and V = 80%) (Ramos Morales et al., 2008a). With respect to the values obtained for N utilization, the first noteworthy aspect is that these were similar to those discussed in a review by Lindberg and Gonda (1996).…”

“…These authors reported that in lactating goats, the largest loss of N intake is via urinary excretion (43%), followed by faecal excretion (29%) and the N in the milk produced (24%). No differences were observed between the legume seeds concerning the quantities of N in milk or in the ratios between the latter and the consumption of N. The total tannin contents (g/kg DM) were 2.0, 26.2, 38.5 and 19.1 for L, FB, BV and V, respectively (Ramos Morales et al., 2008a). Therefore, this parameter did not determine the N utilization of the diets provided, with respect to milk production.…”

“…If Lys and Met, or both, appear to be the most limiting amino acids in milk protein production, in a majority of feeding situations, the responses obtained on using different protein sources may, in principle, be considered to be due to the Lys and Met content of ruminally non‐degraded protein intake (Schwab et al., 1992). In a previous study, the amino acid composition of the ruminally non‐degraded protein of each legume seed was determined (Ramos Morales et al., 2008a). The levels of Lys plus Met for this protein fraction, in the case of L, FB, BV and V were (g/100 g total amino acids): 12.3, 10.2, 12.1 and 10.8, respectively, and the milk N/N balance ratio of the corresponding diets were: 0.543, 0.467, 0.538 and 0.527.…”

“…Earlier studies dealing with the legume seeds in our group fundamentally consisted of the characterization of four legume seeds of local varieties: lupins ( Lupinus albus , moltolupa variety), faba beans ( Vicia faba , alameda variety), bitter vetch ( Vicia ervilia , moro variety) and vetch ( Vicia sativa , filon variety). In these studies, the chemical composition, the ruminal degradability of their dry matter and crude protein, the possible correction of these values for particle loss, the intestinal digestibility of the non‐degradable protein fraction, the amino acid profile of their protein and the proportion of the latter that is non‐degradable was determined (Ramos Morales et al., 2008a,b). The present study focused on the utilization of N and energy of diets in which 30% of the protein was derived from one of the legume seeds studied.…”