Relationships Between Fat and Cholesterol Contents and Fatty Acid Composition in Different Meat-Producing Animal Species

Probiotics Increase Intramuscular Fat and Improve the Composition of Fatty Acids in Sunit Sheep through the Adenosine 5'-Monophosphate-Activated Protein Kinase (AMPK) Signaling Pathway

This experiment aims to investigate the impact of probiotic feed on growth performance, carcass traits, plasma lipid biochemical parameters, intramuscular fat and triglyceride content, fatty acid composition, mRNA expression levels of genes related to lipid metabolism, and the activity of the enzyme in Sunit sheep. In this experiment, 12 of 96 randomly selected Sunit sheep were assigned to receive the basic diet or the basic diet supplemented with probiotics. The results showed that supplementation with probiotics significantly increased the loin eye area, and decreased plasma triglycerides and free fatty acids, increasing the content of intramuscular fat and triglycerides in the muscle and improving the composition of the fatty acids. The inclusion of probiotics in the diet reduced the expression of adenosine 5'-monophosphate-activated protein kinase alpha 2 (AMPKα2) mRNA and carnitine palmitoyltransferase 1B (CPT1B) mRNA, while increasing the expression of acetyl-CoA carboxylase alpha (ACCα) mRNA, sterol regulatory element-binding protein-1c (SREBP-1c) mRNA, fatty acid synthase mRNA, and stearoyl-CoA desaturase 1 mRNA. The results of this study indicate that supplementation with probiotics can regulate fat deposition and improves the composition of fatty acids in Sunit sheep through the signaling pathways AMPK-ACC-CPT1B and AMPK-SREBP-1c. This regulatory mechanism leads to an increase in intramuscular fat content, a restructuring of muscle composition of the fatty acids, and an enhancement of the nutritional value of meat. These findings contribute to a better understanding of the food science of animal resources and provide valuable references for the production of meat of higher nutritional value.

Effects of Sex and Hunting Season on Carcass and Meat Quality Characteristics of the Brown Hare (Lepus europaeus)

The objective of the study was to determine the effects of sex and hunting season on the carcass, meat and fat quality of hunted brown hares (Lepus europaeus). Twenty-two hares of both sexes hunted in winter (December) during two hunting seasons in accordance with the law on hunting in Lithuania were evaluated using reference methods The data were subjected to two-factor analysis of variance in the general linear (GLM) procedure. No significant differences in carcass measurements and muscularity or internal organs between the sexes of brown hares were found; however, the hunting season appeared to affect the size of hares. The biceps femoris (BF) thigh muscle of males had lower (p < 0.05) dry matter content and higher (p < 0.05) drip loss compared with females. The hunting season demonstrated an effect (p < 0.001) on protein and hydroxyproline contents in the longissimus thoracis et lumborum (LTL) and affected dry matter, protein and hydroxyproline contents (p < 0.05, p < 0.001 and p < 0.01, respectively) in BF muscles, and differences in the colour of muscles were also observed. The shear force in the Warner-Bratzler (WB) test was higher (p < 0.001 and p < 0.01, respectively) for LTL and BF muscles during the first hunting season. The hunting season did not affect the total SFA in the intramuscular fat (IMF) of all the tissues, but it affected levels of monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids in the muscles. No differences were found in the total saturated fatty acids (SFA) of both muscles between the sexes, but females demonstrated lower (p < 0.05 and p < 0.01, respectively) and more favourable n-6/n-3 PUFA ratios in the muscles and fat and a lower (p < 0.05) thrombogenic (TI) index in the LTL compared with males.

RNA sequencing analysis of the longissimus dorsi to identify candidate genes underlying the intramuscular fat content in Anqing Six-end-white pigs

Intramuscular fat (IMF) is a significant marker for pork quality. The Anqing Six-end-white pig has the characteristics of high meat quality and IMF content. Owing to the influence of European commercial pigs and a late start in resource conservation, the IMF content within local populations varies between individuals. This study analyzed the longissimus dorsi transcriptome of purebred Anqing Six-end-white pigs with varying IMF content to recognize differentially expressed genes. We identified 1528 differentially expressed genes between the pigs with high (H) and low (L) IMF content. Based on these data, 1775 Gene Ontology terms were significantly enriched, including lipid metabolism, modification and storage, and regulation of lipid biosynthesis. Pathway analysis revealed 79 significantly enriched pathways, including the Peroxisome proliferator-activated receptor and mitogen-activated protein kinase signaling pathways. Moreover, gene set enrichment analysis indicated that the L group had increased the expression of genes related to ribosome function. Additionally, the protein-protein interaction network analyses revealed that VEGFA, KDR, LEP, IRS1, IGF1R, FLT1 and FLT4 were promising candidate genes associated with the IMF content. Our study identified the candidate genes and pathways involved in IMF deposition and lipid metabolism and provides data for developing local pig germplasm resources.

Comparison of Lipid Properties and Cadmium and Lead Content in Red Deer (Cervus elaphus) Meat from Three Feeding Grounds

Simple Summary

As a product originating from the most natural living conditions with free foraging, red deer (Cervus elaphus) meat is becoming increasingly popular among consumers. A greater supply of this type of meat can be ensured by dynamically developing red deer farming on permanent grasslands. The study presents a comparison of the properties of lipids and the content of cadmium and lead in the LL and SM muscles of red deer kept in forest, organic farm, and conventional farm feeding grounds. The greater species and phytoncide diversity in the organic feeding ground enriched the quantitative profile and significantly increased the content of beneficial polyunsaturated fatty acids (FAs) (CLA—conjugated linoleic acid, ALA—alpha-linolenic acid, AA—arachidonic acid, and EPA—eicosapentaenoic acid) and the sum of polyunsaturated fatty acids (PUFAs), n-6 PUFA, and n-3 PUFA, in comparison with conventional farm and forest feeding grounds. It also contributed to a significantly lower n-6/n-3 ratio in both muscles. The study provides valuable data on the nutritional value and ecological safety of venison, which should be regarded as a health-enhancing food product. Furthermore, the present results can help breeders to make decisions about the locations of farms and the choice of red deer nutrition strategies.

Abstract

The aim of the study was to compare the properties of lipids and the content of cadmium and lead in the meat of red deer (Cervus elaphus) kept in a forest feeding ground (FFG) and on organic and conventional farms in Poland. Longissimus lumborum (LL) and Musculus semimembranosus (SM) muscles were collected for the study from 36 red deer carcasses in an equal sex and age ratio (3 and 4 years old). From April to October, the animals consumed only the vegetation growing in the feeding grounds. The floristic and phytoncide composition, as well as the fodder value, of the feeding grounds were assessed. Additionally, the intramuscular fat and cholesterol content, the profile, sum, and ratios of fatty acids (FAs), lipid nutraceutical parameters, and cadmium and lead content were determined in LL and SM. The plant composition comprised 116 species in the organic feeding ground (OFG) and 78 species in the conventional feeding ground (CFG). The LL and SM muscles of the red deer from the organic and forest feeding grounds exhibited significantly lower amounts of fat and cholesterol than those from the conventional system. The differences in the fatty acid composition between the three groups were quite small. Differences in intramuscular fat content contributed to a higher percentage of PUFAs in the FFG and OFG, in comparison to the CFG. In all types of feeding ground, the cadmium (0.002 to 0.008 mg/kg) and lead (0.009 to 0.019 mg/kg) content determined in the meat did not pose a threat to consumers.

Effect of Breed and Finishing Diet on Chemical Composition and Quality Parameters of Meat from Burguete and Jaca Navarra Foals

The purpose of this study was to investigate the influence of breed, Jaca Navarra (JN) vs. Burguete (BU), and finishing diet, conventional concentrate and straw, diet 1 (D1), vs. silage and organic feed, diet 2 (D2), on chemical composition and quality parameters of the longissimus thoracis et lumborum muscle from forty-six foals. Animals were reared under a semi-extensive system and slaughtered at a mean age of 21 months. The results reported that both studied effects had a significant (p < 0.05) impact on meat quality; however, it was the breed to strongly influence the majority of the parameters evaluated. In particular, BU foals reported the highest amounts of intramuscular fat, positively affecting the meat properties of marbling and texture traits. Moreover, this group presented higher values for L* and b* and the lowest cholesterol contents. As regards the diet, D1 increased the fat content in foals supplemented with this diet, improving the organoleptic properties of this group. On the other hand, the combination of silage and organic feed (D2) had an opposite trend. Thus, both BU and D1 groups presented enhanced quality attributes, such as marbling, juiciness and reduced hardness, which are some of the most demanded by meat consumers.

The Effect of Hybrid Barley in the Diets of Fattening Pigs on Pork Oxidative Stability Related to the Fatty Acid Profile

Feed determines the quality of pork meat, in which the composition of the fatty acid (FA) profile is one of the easiest to modify by the application of selected feed components. Barley grains are considered to have an impact on meat quality, including pork; however, there are still limited data on the use of hybrid barley in fattening pigs' nutrition in relation to meat quality. The aim of this study was to determine the relation between meat quality, i.e., its oxidative stability, especially the FA profile, and fattening pigs' diets with hybrid barley and/or wheat. In group I, hybrid barley (HB) composed 80% of the feed; in group II, a mixture of (40% each) wheat and barley was used; and in group III, wheat (W) composed 80% of the feed. Meat samples were taken from twelve randomly selected carcasses chosen from each group. The meat analyses covered the physicochemical and sensory traits. The results showed that the pork meat of fattening pigs fed fodder with 80% HB had decreased palmitic acid concentrations and increased oleic acid concentrations. The meat of these pigs was characterised by the best marbling, which was closely related to its juiciness after thermal processing and determined its final culinary quality. Moreover, the meat from these pigs exhibited a reddish colour, before and after thermal processing. In summary, the application of hybrid barley into pig nutrition improved the quality of the culinary meat.