Effect of dietary nutrition on tail fat deposition and evaluation of tail-related genes in fat-tailed sheep

BACKGROUND: The effects of dietary nutrition on tail fat deposition and the correlation between production performance and the Hh signaling pathway and OXCT1 were investigated in fat-tailed sheep. Tan sheep were fed different nutritional diets and the variances in tail length, width, thickness and tail weight as well as the mRNA expression of fat-related genes (C/EBPα, FAS, LPL, and HSL) were determined in the tail fat of sheep at three different growth stages based on their body weight. Furthermore, the correlations between tail phenotypes and the Hedgehog (Hh) signaling pathway components (IHH, PTCH1, SMO, and GLI1) and OXCT1 were investigated. RESULTS: C/EBPα, FAS, LPL, and HSL were expressed with differences in tail fat of sheep fed different nutritional diets at three different growth stages. The results of the two-way ANOVA showed the significant effect of nutrition, stage, and interaction on gene expression, except the between C/EBPα and growth stage. C/EBPα, FAS, and LPL were considerably correlated with the tail phenotypes. Furthermore, the results of the correlation analysis demonstrated a close relationship between the tail phenotypes and Hh signaling pathway and OXCT1. CONCLUSIONS: The present study demonstrated the gene-level role of dietary nutrition in promoting tail fat deposition and related tail fat-related genes. It provides a molecular basis by which nutritional balance and tail fat formation can be investigated and additional genes can be identified. The findings of the present study may help improve the production efficiency of fat-tailed sheep and identify crucial genes associated with tail fat deposition.

Use of green fluorescent protein to monitor Lactobacillus plantarum in the gastrointestinal tract of goats

The experiment aimed to specifically monitor the passage of lactobacilli in vivo after oral administration. The green fluorescent protein (GFP) gene was cloned downstream from the constitutive p32 promoter from L. lactis subsp. cremoris Wg2. The recombinant expression vector, pLEM415-gfp-p32, was electroporated into Lactobacillus plantarum (L. plantarum) isolated from goat. Green fluorescent protein (GFP) was successfully expressed in L. plantarum. After 2 h post-administration, transformed Lactobacillus could be detectable in all luminal contents. In the rumen, bacteria concentration initially decreased, reached the minimum at 42 h post-oral administration and then increased. However, this concentration decreased constantly in the duodenum. This result indicated that L. plantarum could colonize in the rumen but not in the duodenum.

mRNA transcription and protein expression of PPARgamma, FAS, and HSL in different parts of the carcass between fat-tailed and thin-tailed sheep

Background The objective of this study was to compare the level differences of mRNA transcription and protein expression of PPARγ, FAS and HSL in different parts of the carcass in different tail-type sheep. Six Tan sheep and six Shaanbei fine-wool sheep aged 9 months were slaughtered and samples were collected from the tail adipose, subcutaneous adipose, and longissimus dorsi muscle. The levels of mRNA transcription and protein expression of the target genes in these tissues were determined by real-time quantitative PCR and western blot analyses. Results The results showed that PPARγ, FAS, and HSL were expressed with spatial differences in tail adipose, subcutaneous adipose and longissimus dorsi muscle of Tan sheep and Shaanbei fine-wool sheep. Differences were also observed between the two breeds. The mRNA transcription levels of these genes were somewhat consistent with their protein expression levels. Conclusion The present results indicated that PPARγ, FAS and HSL are correlated with fat deposition, especially for the regulating of adipose deposition in intramuscular fat, and that the mRNA expression patterns are similar to the protein expression patterns. The mechanism requires clarification in further studies.

PPARgamma FAS, HSL mRNA and protein expression during Tan sheep fat-tail development

Background The objective of this study was to investigate proliferator-activated receptor (PPARγ), fatty acid synthase (FAS) and hormone-sensitive lipase (HSL) mRNA and protein expression in fat tails of Tan sheep. Rams from different developmental stages (aged 3, 6, 9, 12, 15 and 18 months) were selected, and their tail measurements including length (L), width (W) and girth (G) were recorded. The mRNA and protein expressions of PPARγ, FAS and HSL were examined by quantitative real-time polymerase chain reaction (PCR) and Western blot. Results The tail measurements increased with age. We observed no significant differences (P > 0.05) of PPARγ mRNA expression between ages 9 and 15 months, and between 12 and 15 months; FAS mRNA expression levels at each developmental stage were observed significantly in Tan sheep (P < 0.05); HSL mRNA expression with no significant differences were only observed between 6 and 15 months (P > 0.05). Significant differences (P < 0.05) of PPARγ, FAS and HSL protein expressions at each developmental stage were observed in Tan sheep. Conclusion We observed that the mRNA expression patterns of PPARγ and FAS decreased first before they increased again and then this process repeated. Conversely, the mRNA expression patterns of HSL increased first before they decreased and then this process repeated. The protein expression patterns of PPARγ and FAS decreased first before they increased again and then this process repeated. Conversely, the protein expression pattern of HSL increased first before it decreased again and then increased again.