The Effect of Replacing Wildrye Hay with Mulberry Leaves on the Growth Performance, Blood Metabolites, and Carcass Characteristics of Sheep

Abstract

The objective of this study was to evaluate the effects of partially substituting for conventional forage, Chinese wildrye (CW), with mulberry leaves (ML) on the growth, digestion, ruminal fermentation, blood metabolites, and meat quality of sheep in a 65-day feedlot study. Thirty-two four-month-old male small-tailed Han sheep (25.15 ± 1.03 kg) were randomly assigned to one of four treatments. The dietary treatments consisted of four proportions of ML (0, 8, 24, and 32%) as a substitute for CW (designated as ML0, ML8, ML24, and ML32, respectively). Rumen digesta and blood samples were collected at day 63 of the trial. Carcass traits were assessed after slaughter at the end of performance period. The results from this study revealed no differences in average daily bodyweight gain (ADG), feed conversion ratio (FCR), and final body weight (FBW) among treatments. The apparent digestibility of dry matter (DM), organic matter (OM), and acid detergent fiber (ADF) was higher in the sheep fed with ML than in those fed CW. The ML24 treatment had a higher digestibility of crude protein (CP) and ether extract (EE). There were no differences (p = 0.13) in ruminal pH values among the treatments. However, there was more microbial protein (p < 0.01) in ML24 and ML32 treatments than the ML0 treatment. Ruminal concentrations of acetate and butyrate were significantly different among treatments, although no difference in concentrations of total volatile fatty acid were found. Additionally, no differences were detected for serum parameters except blood urea nitrogen (BUN). No differences were observed for carcass weight (p = 0.62), dressing percentage (p = 0.31) or longissimus dorsi muscle (LM) area (p = 0.94) among treatments. However, intramuscular fat was higher in the ML24 treatment than in the ML0 treatment. (p < 0.01). There were higher pH values of the 24-h longissimus dorsi in the ML24 treatment than in the ML0 treatment. In addition, the saturated fatty acid (SFA) content was lower (p < 0.01) and the monounsaturated fatty acid (MUFA) content higher (p < 0.01) in the ML24 treatment than in the ML0 treatment. In conclusion, the partially substitution of mulberry leaves for Chinese wildrye in the diet of sheep had a beneficial influence on the growth performance, blood metabolites and carcass characteristics. The inclusion of 24% (air dry basis) mulberry leaf hay in the ration of sheep is recommended based on these findings.

Impact of dietary Lactobacillus supplementation on intramuscular fat deposition and meat quality of Sunit sheep

“…Therefore, IMF was not only one of the nutrients but also a high content of IMF was beneficial to improve the edible quality of meat. There were some ways to increase IMF content, for example, Sun et al (2020) suggested that the IMF deposition of sheep was promoted by mulberry leaves diets which may be related to the fact that mulberry leaf flavonoids can increase insulin levels in animals. Yang et al (2019) indicated a higher dosage of nicotinic acid dietary increased the IMF deposition by upregulating the expression of genes related to adipocyte differentiation, adipogenesis, and lipid and glucose metabolism based on transcriptomics.…”

Potential of feeding fresh and conserved mulberry leaf in ruminants and its impact on dry matter intake, digestibility, milk production, milk composition and meat quality: A review

“…Therefore, ensiling of mulberry leaves and utilization in the ruminant's diet could be possible without affecting the DMI. However, a recent study of Sun et al (2020) reported that DMI increase numerically in treatments that included dry mulberry leaves in the diet. That could be due to the low NDF and high CP contents in mulberry leaves, making this forage a palatable feed for ruminants.…”

“…As it has been reported in many studies that mulberry leaves could be used in livestock and poultry feeding (Sánchez, 1999;Al-Kirshi et al, 2012;Margareta et al, 2015;Wang et al, 2017a;Hao et al, 2020;Li et al, 2020;Ouyang et al, 2020;Sun et al, 2020;Wang et al, 2020a;Wang et al, 2020b;Hao et al, 2021). However, a good feedstuff should be conveniently conserved and utilized.…”

Physicochemical Properties and Elimination of the Activity of Anti-Nutritional Serine Protease Inhibitors from Mulberry Leaves

“…Recently, mulberry leaves have become high-quality animal feed due to their high yield, low cost, good palatability and abundant protein content. As the feed of pigs, sheep, chicken broilers and other livestock, mulberry leaves can improve the conversion efficiency of feed nutrition in animals and enhance the quality of livestock and poultry products [ 7 , 8 , 9 ]. This not only alleviates the shortage of high-quality forage resources to a certain extent but also avoids the waste of mulberry-leaf resources and increases the comprehensive economic benefits of the sericulture industry.…”

“…However, mulberry leaves may contain protease inhibitors, tannic acid, lectins and other anti-nutritional factors [ 10 , 11 ]. Large additions would seriously interfere with the metabolism and absorption of feed nutrients in animals, consequently affecting animal health and the yield and quality of livestock and poultry products, which would greatly limit the development and large-scale application of mulberry leaves resources in animal feed [ 8 , 12 , 13 ].…”