Small Tail Han Research Articles

A comparison of transcriptomic patterns measured in the skin of Chinese fine and coarse wool sheep breeds

We characterised wool traits, and skin gene expression profiles of fine wool Super Merino (SM) and coarse wool Small Tail Han (STH) sheep. SM sheep had a significantly higher total density of wool follicles, heavier fleeces, finer fibre diameter, and increased crimp frequency, staple length and wool grease (lanolin) production. We found 435 genes were expressed at significantly different levels in the skin of the two breeds (127 genes more highly in SM and 308 genes more highly in STH sheep). Classification of the genes more highly expressed in SM sheep revealed numerous lipid metabolic genes as well as genes encoding keratins, keratin-associated proteins, and wool follicle stem cell markers. In contrast, mammalian epidermal development complex genes and other genes associated with skin cornification and muscle function were more highly expressed in STH sheep. Genes identified in this study may be further evaluated for inclusion in breeding programs, or as targets for therapeutic or genetic interventions, aimed at altering wool quality or yield. Expression of the lipid metabolic genes in the skin of sheep may be used as a novel trait with the potential to alter the content or properties of lanolin or the fleece.

Cloning, Expression and Polymorphisms of the 3' UTR of Ovine NOBOX Gene

The oocyte-specific transcription factor newborn ovary homeobox (NOBOX) plays essential roles in regulating various stages of oogenesis, folliculogenesis and early embryonic development. The nucleotide sequence of 3'-untranslated region (3’UTR) of the ovine NOBOX gene (Accession No. KM090856) is detailed in the present report. Semi-quantitative RT-PCR analysis demonstrated that the ovine NOBOX transcript was mainly expressed in ovary. Two single nucleotide polymorphisms (SNPs) were detected in 3’UTR of NOBOX gene and two restriction site for endonuclease NOBOX-AfaI and NOBOX-BalI had also been found. Moreover, for the first time an association was reported between NOBOX gene polymorphism and prolificacy traits in Small Tailed Han sheep. Marker-trait association analyses showed that the NOBOX-AfaI and NOBOX-BalI genotypes had significant effect on the litter size traits in small tailed han ewes (p less than 0.05). In conclusion, these preliminary results indicated that NOBOX-AfaI and NOBOX-BalI loci in NOBOX gene may be a potential marker for improving prolificacy traits in sheep.

Comparative transcriptome profiling of longissimus muscle tissues from Qianhua Mutton Merino and Small Tail Han sheep.

The Qianhua Mutton Merino (QHMM) is a new sheep (Ovis aries) variety with better meat performance compared with the traditional local variety Small Tail Han (STH) sheep. We aimed to evaluate the transcriptome regulators associated with muscle growth and development between the QHMM and STH. We used RNA-Seq to obtain the transcriptome profiles of the longissimus muscle from the QHMM and STH. The results showed that 960 genes were differentially expressed (405 were up-regulated and 555 were down-regulated). Among these, 463 differently expressed genes (DEGs) were probably associated with muscle growth and development and were involved in biological processes such as skeletal muscle tissue development and muscle cell differentiation; molecular functions such as catalytic activity and oxidoreductase activity; cellular components such as mitochondrion and sarcoplasmic reticulum; and pathways such as metabolic pathways and citrate cycle. From the potential genes, a gene-act-network and co-expression-network closely related to muscle growth and development were identified and established. Finally, the expressions of nine genes were validated by real-time PCR. The results suggested that some DEGs, including MRFs, GXP1 and STAC3, play crucial roles in muscle growth and development processes. This genome-wide transcriptome analysis of QHMM and STH muscle is reported for the first time.

Ontogenetic Expression of Lpin2 and Lpin3 Genes and Their Associations with Traits in Two Breeds of Chinese Fat-tailed Sheep.

Lipins play dual function in lipid metabolism by serving as phosphatidate phosphatase and transcriptional co-regulators of gene expression. Mammalian lipin proteins consist of lipin1, lipin2, and lipin3 and are encoded by their respective genes Lpin1, Lpin2, and Lpin3. To date, most studies are concerned with Lpin1, only a few have addressed Lpin2 and Lpin3. Ontogenetic expression of Lpin2 and Lpin3 and their associations with traits would help to explore their molecular and physiological functions in sheep. In this study, 48 animals with an equal number of males and females each for both breeds of fat-tailed sheep such as Guangling Large Tailed (GLT) and Small Tailed Han (STH) were chosen to evaluate the ontogenetic expression of Lpin2 and Lpin3 from eight different tissues and months of age by quantitative real-time polymerase chain reaction (PCR). Associations between gene expression and slaughter and tail traits were also analyzed. The results showed that Lpin2 mRNA was highly expressed in perirenal and tail fats, and was also substantially expressed in liver, kidney, reproductive organs (testis and ovary), with the lowest levels in small intestine and femoral biceps. Lpin3 mRNA was prominently expressed in liver and small intestine, and was also expressed at high levels in kidney, perirenal and tail fats as well as reproductive organs (testis and ovary), with the lowest level in femoral biceps. Global expression of Lpin2 and Lpin3 in GLT both were significantly higher than those in STH. Spatiotemporal expression showed that the highest levels of Lpin2 expression occurred at 10 months of age in two breeds of sheep, with the lowest expression at 2 months of age in STH and at 8 months of age in GLT. The greatest levels of Lpin3 expression occurred at 4 months of age in STH and at 10 months of age in GLT, with the lowest expression at 12 months of age in STH and at 8 months of age in GLT. Breed and age significantly influenced the tissue expression patterns of Lpin2 and Lpin3, respectively, and sex significantly influenced the spatiotemporal expression patterns of Lpin3. Meanwhile, Lpin2 and Lpin3 mRNA expression both showed significant correlations with slaughter and tail traits, and the associations appear to be related with the ontogenetic expression as well as the potential functions of lipin2 and lipin3 in sheep.

MRNA Expression of Ovine Angiopoietin-like Protein 4 Gene in Adipose Tissues

Angiopoietin-like protein 4 (ANGPTL4) is involved in a variety of functions, including lipoprotein metabolism and angiogenesis. To reveal the role of ANGPTL4 in fat metabolism of sheep, ovine ANGPTL4 mRNA expression was analyzed in seven adipose tissues from two breeds with distinct tail types. Forty-eight animals with the gender ratio of 1:1 for both Guangling Large Tailed (GLT) and Small Tailed Han (STH) sheep were slaughtered at 2, 4, 6, 8, 10, and 12 months of age, respectively. Adipose tissues were collected from greater and lesser omental, subcutaneous, retroperitoneal, perirenal, mesenteric, and tail fats. Ontogenetic mRNA expression of ANGPTL4 in these adipose tissues from GTL and STH was studied by quantitative real time polymerase chain reaction. The results showed that ANGPTL4 mRNA expressed in all adipose tissues studied with the highest in subcutaneous and the lowest in mesenteric fat depots. Months of age, tissue and breed are the main factors that significantly influence the mRNA expression. These results provide new insights into ovine ANGPTL4 gene expression and clues for its function mechanism.

Transcriptome analysis of skeletal muscle at prenatal stages in Polled Dorset versus Small-tailed Han sheep.

The objectives of the present study were to identify additional genes that may play important roles in the regulation of skeletal muscle growth and development, and to provide fundamental information for understanding the underlying molecular mechanisms. Eighteen cDNA libraries were constructed from the longissimus muscle of Polled Dorset (PD) and Small-tailed Han (SH) fetuses. To reveal the differences between the two species, we analyzed the differences in gene expression in 60-, 90- and 120-day fetal skeletal muscle by applying Agilent ovine genome-wide microarray. In this study, we obtained 17,704 genes using a chip containing 39,242 probes. There were 88 differentially expressed genes in the 60-day group (P < 0.05), 128 genes in the 90-day group (P < 0.05), and 340 genes in the 120-day group (P < 0.05) between the two breeds. The differentially expressed genes were grouped in different GO categories and signaling pathways. These results suggested that there are many genetic differences in the muscle growth and development transcriptomes between these two breeds. This study laid the foundation for future genomic research in sheep.

Characterization and comparative profiling of ovarian microRNAs during ovine anestrus and the breeding season.

BackgroundSeasonal estrus is a critical limiting factor of animal fecundity, and it involves changes in both ovarian biology and hormone secretion in different seasons. Previous studies indicate that two classes of small RNAs (miRNAs and piRNAs) play important regulatory roles in ovarian biology. To understand the roles of small RNA-mediated post-transcriptional regulation in ovine seasonal estrus, the variation in expression patterns of ovarian small RNAs during anestrus and the breeding season were analyzed using Solexa sequencing technology. In addition, reproductive hormone levels were determined during ovine anestrus and the breeding season.ResultsA total of 483 miRNAs (including 97 known, 369 conserved and 17 predicated novel miRNAs), which belong to 183 different miRNA families, were identified in ovaries of Tan sheep and Small Tail Han (STH) sheep. Compared with the three stages of the breeding season, 25 shared significantly differentially expressed (including 19 up- and six down-regulated) miRNAs were identified in ovine anestrus. KEGG Pathway analysis revealed that the target genes for some of the differentially expressed miRNAs were involved in reproductive hormone related pathways (e.g. steroid biosynthesis, androgen and estrogen metabolism and GnRH signaling pathway) as well as follicular/luteal development related pathways. Moreover, the expression of the differentially expressed miRNAs and most of their target genes were negatively correlated in the above pathways. Furthermore, the levels of estrogen, progesterone and LH in ovine anestrus were significantly lower than those in the breeding season. Combining the results of pathway enrichment analysis, expression of target genes and hormone measurement, we suggest that these differentially expressed miRNAs in anestrus might participate in attenuation of ovarian activity by regulating the above pathways. Besides miRNAs, a large and unexpectedly diverse set of piRNAs were also identified.ConclusionsThe miRNA profiles of ovine ovaries in anestrus were presented for the first time. The identification and characterization of miRNAs that are differentially expressed between ovine anestrus and the breeding season will help understanding of the role of miRNAs in the regulation of seasonal estrus, and provides candidates for determining miRNAs which could be potentially used to regulate ovine seasonal estrus.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2164-15-899) contains supplementary material, which is available to authorized users.

A New Experimental Animal Model of Chronic Cervical Compressive Myelopathy

Introduction Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction among adults over the age of 55?In China the morbidity of CSM is 10%. However, the pathobiology of CSM is still unclear which limits therapeutic advances for this common cause of neurological dysfunction. The clinical course of the disease remains unpredictable. The lack of reliable animal models of CSM has been a restriction to advancing the field. Up to now, various animal model of CSM have been made. Although some of these studies have impressive progress, they also have significant defects. Many of these models fail to model the chronic and progressive nature of the disease since they do not accurately reproduce the main human neuropathological and clinical features of CSM, In this study we report a new model of CSM in sheep. It is more accurate and stable than previous models. Moreover, the entire course of compression is digitized. Materials and Methods A Silicone sealed compression device is assembled with a stepping motor, gear reducer and a push rod. The compression device is connected to a circuit board which contains a bluetooth module and a control chip. Power supply is a lithium battery. Circuit board is also well sealed with silicone. It is controlled via an Android cellphone in vitro. Six male small tailed han sheep were divided into two groups randomly, four in experimental group and two in control group. The compression device was implanted into intervertebral space of C4/C5 and fixed. Circuit board was implanted subcutaneously. The control group ran no compression after surgery. Animals of each group were carried on a routine CT inspection right after the surgery. The front end of the push rod was adjusted to the posterior edge of the cervical vertebral. The experimental group pushed 0.4 mm each week while awake. Tarlov scores were assessed in each group before and after push. Results In the course of the experiment, one sheep of the experimental group appeared malfunction of the circuit board subskin. The dysfunctional board was replaced during an extra operation. The Tarlov sores of the experimental group didn't change before and after each time of push. No behavioral changes were noted in control group. While sheep in the experimental group showed gradually changes of gait. The final Tarlov score was four in three sheep and three in one sheep of the experimental group and the final radiological findings showed that the average spinal canal encroachment rate was 60.6% in the experimental group after 18 weeks’ observation. Conclusion This animal model can be used to generate controllable compression to spine operated by a digitized system. No invasive procedures were applied during the experiment. In next stage of experiment we could get specimens and run pathological tests. Disclosure of Interest None declared

Predictive potential of microsatellite markers on heterosis of fecundity in crossbred sheep

Small Tail Han (STH) sheep is a famous Chinese local breed and has perfect prolificacy performance, but it is inferior to imported mutton sheep breeds on meat production. In this study, six imported male sheep populations (White Suffolk, Black Suffolk, Texel, Dorper, South African Mutton Merino and East Friesian) were crossbred with STH female sheep respectively. The heterosis values of litter size, average daily gain (ADG) and feed conversion ratio (FCR) of crossbred sheep were analyzed for seeking the optimal cross. Meanwhile 28 microsatellite markers were used to measure the genetic distance between imported populations and STH population. Regression between the genetic distance and heterosis was analyzed for evaluating potential of microsatellite on predicting heterosis. Results showed a significant positive linear correlation (r = 0.892, P < 0.05) between heterosis of litter size and genetic distance D (A) of six crosses. This implied that these microsatellite markers had moderate potential to forecast heterosis of litter size in sheep. Results of this study also indicated that South African Mutton Merino and East Friesian sheep would be the optimal sire breeds for the litter size and might bring the greatest economic benefit in six imported populations; Suffolk sheep could be prior consideration as sire breeds when breeding objective focused on ADG. Finally these results provided valuable information for Chinese sheep industry.