Effects of Feeding Rumen-Protected Sunflower Seed and Meal Protein on Feed Intake, Diet Digestibility, Ruminal, Cecal Fermentation, and Growth Performance of Lambs

Abstract

The objective of this study was to analyze the efficacy of a treatment (MAH) of sunflower seed (SS) and meal (SM) with a malic acid solution (1 M; 400 mL/kg) and heating (150 °C, 2 h) to protect protein against rumen degradation and to improve the growth of lambs. Two homogeneous groups of 12 Lacaune lambs each (14.2 ± 0.35 kg body weight) were fed either a concentrate including untreated SS and SM or a concentrate with MAH-treated SS and SM. Lambs were fed concentrate and barley straw ad libitum for 40 days (about 26 kg body weight); feed intake and growth of lambs were recorded; blood samples were taken on days 0, 20, and the slaughter day for analysis of urea-N and amino acid-N; diet digestibility was determined; and ruminal and cecal samples were collected after slaughter. The in vitro incubation of both concentrates with sheep ruminal fluid for 12 h showed that the MAH-treatment tended to reduce NH3-N concentrations and increased propionate production. However, there were no differences (p > 0.05) between groups in any of the tested variables in the in vivo trial.

Effect of a Diet Supplemented with Malic Acid–Heat (MAH) Treated Sunflower on Carcass Characteristics, Meat Composition and Fatty Acids Profile in Growing Lambs

“…As reported by [7], the MAH treatment did not affect feed intake, average daily gain and hot and cold carcass weights, which reached 12.7 and 12.4 kg for control and 13.7 and 12.8 kg for MAH-fed group, respectively. There were no effects (p ≥ 0.134) of MAH concentrate on cooling losses, carcass conformation measurements and metacarpus weight and length (Table 1), which is in agreement with the lack of differences between groups observed in the carcass weights.…”

“…Diets, animals, and experimental procedures were detailed described by Haro et al [7], and are briefly summarized below. Animals were cared for and managed in accordance with the Spanish guidelines for experimental animal protection, and the experimental procedures were approved by the General Direction of Livestock and Agriculture of the Community of Madrid (Approval number PROEX 035/17).…”

“…Because both carcass characteristics and meat quality in ruminants are strongly affected by the diet of the animals, the objective of the study was to evaluate the effects of feeding MAH-treated SM and SS on carcass characteristics and meat composition and FA profile of light lambs. This is a companion paper to Haro et al [7], which reported the effects of the MAH treatment on growth performance, diet digestibility, blood parameters, and ruminal fermentation of growing lambs.…”

“…In the MAH concentrate, both SM and SS were included after being treated for protecting sunflower protein against ruminal degradation. The MAH treatment has been detailed by Haro et al [7] and consisted in spraying both feeds with a 1 M malic acid solution at a rate of 400 mL per kg of feed and drying the mixture at 150 • C for 2 h. Chemical composition was similar in both concentrates, which contained as average 941, 155, 188, and 69.9 g of organic matter, crude protein, neutral detergent fiber and acid detergent fiber per kg, respectively [6].…”

“…All chemical analyses were performed in duplicate unless otherwise stated. Chemical composition of feeds was analyzed according the Association of Official Analytical Chemists [15] procedures as described by [7].…”