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This study aimed to analyze the growth performance, antioxidant activity, serum lipid profile, meat quality, and lipid metabolism of broiler chickens fed mixtures containing Enteromorpha polysaccharide (EP) and yeast glycoprotein (YG). A total of 400 one-day-old broiler chickens were randomly divided into 4 treatment groups of 10 replicates with 10 birds each replicate. The dietary treatments consisted of the control group (fed basal diet), and diets supplemented with Enteromorpha polysaccharide (EP; 400 mg/kg), yeast glycoprotein (YG;400 mg/kg), and EP+YG (200 mg/kg EP + 200 mg/kg YG). Compared with the control group, EP+YG supplementation enhanced growth performance and significantly reduced (P < 0.05) serum total triglyceride (TG), cholesterol (CHOL), and low-density lipoprotein LDL levels, and increased high-density lipoprotein (HDL) levels. Besides, birds fed EP+YG supplemented diet exhibited higher (P < 0.05) serum catalase (CAT), total antioxidant capacity, superoxide dismutase (SOD), and lower malonaldehyde (MDA) activities, and upregulated expressions of related genes, such as nuclear factor-erythroid factor 2-related factor 2 (NRF2), SOD1, and glutathione peroxidase 4 (GPX4) in the liver and intestinal tissues than the control group. Interestingly, higher (P < 0.05) serum SOD and lower MDA contents were observed in the EP+YG group than in either EP or YG group, suggesting a synergetic effect. Breast meat from EP+YG supplemented group had significantly higher redness value (a*), and lower pH24, total saturated fatty acid profiles, C14:0, C16:0, C18:0 fatty acid, atherogenic index, and thrombogenicity index than meat from the control group (P < 0.05). Furthermore, the mRNA expressions of fatty acid synthesis genes were downregulated (P < 0.05), whereas lipid β-oxidation-related genes were upregulated (P < 0.05) in the liver of the EP+YG supplemented group than in the control group. Overall, our data suggest that dietary EP+YG inclusion may have a synergistic effect, and therefore improve growth performance, regulate serum biochemical indexes, enhance antioxidant activity, and modulate lipid metabolism in broilers, indicating that it is a potential feed additive for chickens., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

This study aimed to evaluate the effects of kisspeptin-54 immunocastration vaccine on performance, carcass characteristics, meat quality, and safety of Yiling goats. Thirty buck goats were randomly assigned into three groups: PVAX-B2L-Kisspeptin-54-asd immunized (PBK-asd), control, and surgically castrated. PBK-asd immunization significantly stimulated serum anti-kisspeptin antibody production and reduced testosterone hormone compared with the control group (p < .05). Interestingly, PBK-asd plasmid did not integrate into the host genome and had no significant effect on growth hormone, body weight, and average daily gain (ADG). Conversely, surgical castration significantly reduced ADG and carcass weight compared to the control group. Furthermore, PBK-asd immunization did not affect carcass characteristics (dressing percentage, loin area, and fat thickness) and meat quality traits (pH, color, cooking loss, drip loss, and shearing force). These results indicate that the Kisspeptin-54 DNA vaccine is safe and has potential to be used as an alternative to surgical castration for goats without negatively affecting carcass and meat quality., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Kisspeptin, a peptide product of KISS1 gene, recently identified as essential upstream gatekeeper in hypothalamic-pituitary-gonadal (HPG) axis. This study was designed to investigate the effect of immunization against kisspeptin-54 on hypothalamic-pituitary-testicular signaling pathway. A total of ten intact 56-days-old ram lambs were used and randomized into the treatment and control groups, which were, respectively immunized by kisspeptin-54 based vaccine and the empty plasmid via intramuscular route. We employed indirect enzyme-linked immunosorbent assay and quantitative real-time PCR to characterize the difference in serum kisspeptin, luteinizing hormone, testosterone hormone concentration and mRNA expression of reproductive-related genes in HPG axis across kisspeptin-54 immunized and control ram lambs. Serum kisspeptin, luteinizing hormone and testosterone concentration in the treatment group was lower (p < 0.05) than that of the control group. Compared with the control group, the mRNA expression of the hypothalamic androgen receptor (AR), KISS1, G protein-coupled receptor (GPR54) and gonadotropin-releasing hormone (GnRH) was altered in the immunized group (p < 0.05). Moreover, mRNA expression of pituitary luteinizing hormone beta (LHβ), follicle stimulating hormone beta (FSHβ), and GnRH receptor as well as, testicular LH receptor and FSH receptor, were remarkably lower (P < 0.05) in the treatment group. We concluded that immunization against kisspeptin-54 reduced serum kisspeptin levels thereby, the normal hypothalamic-pituitary-testicular signaling pathway disrupted. This data provides a great insight for the use of kisspeptin to regulate reproduction., (Copyright © 2018 Elsevier Inc. All rights reserved.)