Backfat thickness and longissimus dorsi real-time ultrasound measurements in light lambs

Association analysis of mitochondrial genome polymorphisms with backfat thickness in pigs

Mitochondrial DNA (mtDNA) variations and associated effects on economic traits have been widely reported in farm animals, as these genetic polymorphisms can affect the efficiency of energy production and cell metabolism. In studies related to metabolism, the deposition of fat was highly correlated with mitochondria. However, the effect of mtDNA polymorphisms on porcine backfat thickness (BFT) remained unclear. In this study, 243 pigs were collected to analyse the relationship between BFT and mtDNA polymorphisms. There were considerable differences in BFT, ranging from 5 mm to 18 mm. MtDNA D-loop sequencing discovered 48 polymorphic sites. Association analysis revealed that 30 variations were associated with BFT (P < 0.05). The polymorphism m.794A > G showed the maximum difference in BFT between A and G carriers, which differed at ∼2.5 mm (P < 0.001). The 48 polymorphic sites generated 22 haplotypes (H1-H22), which clustered into 4 haplogroups (HG1-HG4). HG1 had a lower BFT value than other three haplogroups (P < 0.01), whereas H4 in HG1 exhibited the lowest BFT of all haplotypes analyzed (P < 0.01). The results of this study highlight an association between mtDNA polymorphisms and BFT, and suggest the potential application of mtDNA in pig molecular breeding practices.

Synchronous feeding of liquid protein source with different grains on performance, digestibility, ruminal fermentation, blood metabolites, and carcass characters in growing lambs

The effects of feeding corn steep liquor (CSL; 420 g/kg crude protein, DM basis) along with different cereal grains on performance, digestibility, blood metabolites, ruminal fermentation, and carcass characters of growing lambs were evaluated. The constant amount of CSL was included in basal diet (100 g/kg, DM basis) and grain sources as experimental treatments were as follows: (1) corn grain (CG), (2) barley grain (BG), or (3) wheat grain (WG). The eighteen individually fed Farahani lambs averaging body weight 32 kg were allocated in completely randomized design (6 lambs/each) in a 9-week trial. The results showed that the greatest intake and gain were found in lambs fed CG in contrast to others. Nitrogen intake was constant among diets; however, the greatest nitrogen efficiency was found for corn grain-fed animals. Digestibility of nutrients were reduced in WG-fed animals in comparison with other grains. Ruminal proportions of propionate and butyrate were reduce in WG-fed lambs. The CG-fed animals displayed greater blood glucose and lower BUN concentrations compared with others. The greatest aspartate aminotransferase concentration as well as the greatest liver fat deposition suggested a dysfunction in liver performance in WG-fed animals. Except than that of a tendency for increment in dressing percentage in CG-fed lambs, no carcass character was differed among treatments. In conclusion, results revealed that feeding liquid protein source (CSL) is recommendable when it has been fed along with corn grain in comparison with barley or wheat grains in growing lambs.

Advances in Sheep and Goat Meat Products Research

The main goal of this chapter was to review the state of the art in the recent advances in sheep and goat meat products research. Research and innovation have been playing an important role in sheep and goat meat production and meat processing as well as food safety. Special emphasis will be placed on the imaging and spectroscopic methods for predicting body composition, carcass and meat quality. The physicochemical and sensory quality as well as food safety will be referenced to the new sheep and goat meat products. Finally, the future trends in sheep and goat meat products research will be pointed out.

Bayesian inference of genetic parameters for ultrasound scanning traits of Kivircik lambs

Ultrasound scanning traits have been adapted in selection programs in many countries to improve carcass traits for lean meat production. As the genetic parameters of the traits interested are important for breeding programs, the estimation of these parameters was aimed at the present investigation. The estimated parameters were direct and maternal heritability as well as genetic correlations between the studied traits. The traits were backfat thickness (BFT), skin+backfat thickness (SBFT), eye muscle depth (MD) and live weights at the day of scanning (LW). The breed investigated was Kivircik, which has a high quality of meat. Six different multi-trait animal models were fitted to determine the most suitable model for the data using Bayesian approach. Based on deviance information criterion, a model that includes direct additive genetic effects, maternal additive genetic effects, direct maternal genetic covariance and maternal permanent environmental effects revealed to be the most appropriate for the data, and therefore, inferences were built on the results of that model. The direct heritability estimates for BFT, SBFT, MD and LW were 0.26, 0.26, 0.23 and 0.09, whereas the maternal heritability estimates were 0.27, 0.27, 0.24 and 0.20, respectively. Negative genetic correlations were obtained between direct and maternal effects for BFT, SBFT and MD. Both direct and maternal genetic correlations between traits were favorable, whereas BFT-MD and SBFT-MD had negligible direct genetic correlation. The highest direct and maternal genetic correlations were between BFT and SBFT (0.39) and between MD and LW (0.48), respectively. Our results, in general, indicated that maternal effects should be accounted for in estimation of genetic parameters of ultrasound scanning traits in Kivircik lambs, and SBFT can be used as a selection criterion to improve BFT.