Combined approaches to reveal genes associated with litter size in Yunshang black goats.

Intensive artificial selection has been imposed in Yunshang black goats, the first black specialist mutton goat breed in China, with a breeding object of improving reproductive performance, which has contributed to reshaping of the genome including the characterization of SNP, ROH and haplotype. However, variation in reproductive ability exists in the present population. A WGS was implemented in two subpopulations (polytocous group, PG, and monotocous group, MG) with evident differences of litter size. Following the mapping to reference genome, and SNP calling and pruning, three approaches - GWAS, ROH analysis and detection of signatures of selection - were employed to unveil candidate genes responsible for litter size. Consequently, 12 candidate genes containing OSBPL8 with the minimum P-value were uncovered by GWAS. Differences were observed in the pattern of ROH between two subpopulations that shared similar low inbreeding coefficients. Two ROH hotspots and 12 corresponding genes emerged from ROH pool association analysis. Based on the nSL statistic, 15 and 61 promising genes were disclosed under selection for MG and PG respectively. Of them, some promising genes participate in ovarian function (PPP2R5C, CDC25A, ESR1, RPS26 and SERPINBs), seasonal reproduction (DIO3, BTG1 and CRYM) and metabolism (OSBPL8, SLC39A5 and SERPINBs). Our study pinpointed some novel promising genes influencing litter size, provided a comprehensive insight into genetic makeup of litter size and might facilitate selective breeding in goats.

Differential expression of Toll-like receptors in goat dominant and nondominant follicles.

The mechanism of dominant follicle selection is unclear because of its physiological complexity. However, some studies have reported that the immune system plays an important role in reproductive physiology. The objective of the current study was to investigate the differential expression of Toll-like receptors (TLRs) in the dominant (DFs) and nondominant follicles (NFs), and to determine the correlation between the expression of TLRs and the related genes, such as WNT4 and FOXL2. In this comparative study, the expression levels of TLRs, WNT4, and FOXL2 genes of DFs and NFs were obtained from three Dazu black goats were estimated using the real-time PCR. Our results showed no significant difference in the expression of seven TLRs (excluding TLR2, TLR5, and TLR8), WNT4, and FOXL2 between the DFs and NFs. In addition, the mRNA expression levels of WNT4 significantly correlated with the relative expression of TLR6 (r = 0.949739, P < 0.01); however, no significant expression of the TLR genes was found to be associated with FOXL2 mRNA expression. Our results support the fact that TLRs are not involved in the process of dominant follicle selection; however, TLR6 might play a role in the development of follicles by interacting with WNT4.

Diosmectite-zinc oxide composite improves intestinal barrier restoration and modulates TGF-ß1, ERK1/2, and Akt in piglets after acetic acid challenge.

The present study evaluated the beneficial effect of diosmectite-zinc oxide composite (DS-ZnO) on improving intestinal barrier restoration in piglets after acetic acid challenge and explored the underlying mechanisms. Twenty-four 35-d-old piglets (Duroc × Landrace × Yorkshire), with an average weight of 8.1 kg, were allocated to 4 treatment groups. On d 1 of the trial, colitis was induced via intrarectal injection of acetic acid (10 mL of 10% acetic acid [ACA] solution for ACA, DS-ZnO, and mixture of diosmectite [DS] and ZnO [DS+ZnO] groups) and the control group was infused with saline. Twenty-four hours after challenged, piglets were fed with the following diets: 1) control group (basal diet), 2) ACA group (basal diet), 3) DS-ZnO group (basal diet supplemented with DS-ZnO), and 4) DS+ZnO group (mixture of 1.5 g diosmectite [DS]/kg and 500 mg Zn/kg from ZnO [equal amount of DS and ZnO in the DS-ZnO treatment group]). On d 8 of the trial, piglets were sacrificed. The results showed that DS-ZnO supplementation improved (P < 0.05) ADG, ADFI, and transepithelial electrical resistance and decreased (P < 0.05) fecal scores, crypt depth, and fluorescein isothiocyanate-dextran 4 kDa (FD4) influx as compared with ACA group. Moreover, DS-ZnO increased (P < 0.05) occludin, claudin-1, and zonula occluden-1 expressions; reduced (P < 0.05) caspase-9 and caspase-3 activity and Bax expression; and improved (P < 0.05) Bcl2, XIAP, and PCNA expression. Diosmectite-zinc oxide composite supplementation also increased (P < 0.05) TGF-ß1 expression and ERK1/2 and Akt activation. These results suggest that DS-ZnO attenuates the acetic acid-induced colitis by improving mucosa barrier restoration, inhibiting apoptosis, and improving intestinal epithelial cells proliferation and modulation of TGF-ß1 and ERK1/2 and Akt signaling pathway.

The effects of 1,4-cyclohexanediol on frozen ram spermatozoa.

In order to improve the quality of frozen spermatozoa of Yunnan semi-fine wool sheep, 1, 4-cyclohexanediol (1, 4-CHD) as a synthetic ice blocker was used for cryopreservation of ram spermatozoa in this study. Briefly, following collection by electric stimulation, equilibration at 5℃ following dilution with the freezing extender, and pre-freezing in liquid nitrogen vapor, the ram spermatozoa were preserved in liquid nitrogen for one month. In addition, the effects of osmolarity of the diluting extenders used for evaluation of frozen spermatozoa quality were also assessed. The results indicated addition of 1, 4-CHD could not increase the motility of ram spermatozoa after cryopreservation and thawing. With the elevation of the concentrations of 1, 4-CHD, the motility and moving velocity of frozen ram spermatozoa showed a steady decrease. Additionally, the presence of 1, 4-CHD cannot increase the percentage of frozen spermatozoa with intact acrosome and membrane. When the isotonic binding buffer was used to dilute the thawed spermatozoa, the percentage of cells labeled with propidium iodide (PI) after cryopreservation in the presence of 1, 4-CHD was significantly higher than that of spermatozoa frozen in the absence of 1, 4-CHD (P < 0.05). However, the percentage of frozen-thawed spermatozoa with exposed PS in the presence of 1, 4-CHD was significantly less than that of spermatozoa frozen in the absence of 1, 4-CHD (P < 0.01). When the basic extenders with an osmolarity of 404mOsm, 528mOsm, 648mOsm, or 853mOsm were used to dilute the frozen-thawed spermatozoa respectively, there is no significant difference between the four groups with respect to the moving velocity and membrane integrity (P > 0.05). In conclusion, the presence of 1, 4-CHD cannot improve the motility, moving velocity, acrosome staus, and membrane integrity of frozen ram spermatozoa. However, 1, 4-CHD may inhibit apoptosis caused by freezing and thawing.

Response to dietary L-glutamine supplementation in weaned piglets: a serum metabolomic comparison and hepatic metabolic regulation analysis.

A novel metabolomic method based on gas chromatography-mass spectrometry was applied to investigate serum metabolites in response to dietary Gln supplementation in piglets. Sixteen, 21-d-old pigs were weaned and assigned randomly to 2 isonitrogenous diets: 1) Gln diet, which contained 1% L-Gln (as-fed basis), and 2) control diet, which contained L-Ala to make this diet isonitrogenous with the Gln diet. Serum samples were collected to characterize metabolites after a 30-d treatment. in addition, 4 liver samples per treatment were collected to examine enzyme activity and gene expression involved in metabolic regulation. Results indicated that 12 metabolites were altered (P < 0.05) by Gln treatment, including carbohydrates, AA, and fatty acids. A leave-one-out cross validation of random forest analysis indicated that Pro was most important among the 12 metabolites. Thus, these data demonstrate that the control and Gln-supplemented pigs differed (P < 0.05) in terms of metabolism of carbohydrates, Pro, Tyr, and glycerophospholipids. Principal component analysis yielded separate clusters of profiles between the Gln and control groups. Metabolic enzyme activities of Ala aminotransferase and hexokinase increased by 26.8% (P = 0.026) and 26.2% (P = 0.004) in the liver of Gln-supplemented pigs vs. control, respectively, whereas pyruvate kinase (PK) activity decreased by 29.1% (P = 0.001). The gene expression of PK in the liver decreased by 66.1% (P = 0.034) by Gln treatment for 30 d. No differences were observed for the mRNA abundance of mammalian target of rapamycin and PPARγ. On the basis of these data, Gln treatment affected carbohydrate, lipid, and AA metabolism in the whole body of the early weaned piglets. These findings provide insight into specific metabolic pathways and lay the groundwork for the complex metabolic alteration in response to dietary Gln supplementation of pigs.

Effect of chito-oligosaccharide on growth performance, intestinal barrier function, intestinal morphology and cecal microflora in weaned pigs.

A total of 180 weanling pigs (21 ± 3 d of age; 5.98 ± 0.04 kg) were used to investigate the effect of chito-oligosaccharide (COS) on growth performance, intestinal barrier function, intestinal morphology, and cecal microflora. Based on initial BW, gender and litter, the pigs were given 5 treatments during a 14-d feeding experiment, including a basal diet (control), 3 diets with COS supplementation (200, 400, or 600 mg/kg), and a diet with colistin sulfate (CSE) supplementation (20 mg/kg). Six randomly selected pigs from each treatment were used to collect serum, duodenal, jejunal, ileal, and cecal samples on d 7 and 14 postweaning. From d 1 to 7 postweaning, pigs fed COS or CSE had greater ADG and ADFI compared with the control pigs. From d 1 to 14, diets with either 400 or 600 mg/kg COS, or 20 mg/kg CSE increased (P < 0.05) ADG and G:F compared with the control diet. No significant differences were observed in ADG, ADFI, and G:F between the pigs fed COS and CSE. Pigs fed either 400 or 600 mg/kg COS, or 20 mg/kg CSE had less (P < 0.05) diamine oxidase (DAO) in the serum, but greater concentration of (P < 0.05) DAO in jejunal mucosa, than the control pigs on d 7 postweaning. Treatments did not affect villous height and crypt depth of the duodenum, jejunum, or ileum. Pigs fed COS at 400 mg/kg had greater (P < 0.05) concentration of Bifidobacteria and Lactobacilli in the cecum than pigs fed the control diet and CSE diet on d 7 postweaning. Supplementation of COS or CSE decreased (P < 0.05) the population of cecal Staphylococcus aureus compared with the control diet on d 7 postweaning. The number of cecal Bifidobacteria in pigs fed 600 mg/kg COS was greater (P < 0.05) than that of pigs fed the control diet or CSE diet on d 14 postweaning. No significant differences were observed in Escherichia coli counts in the cecum among treatments. The present results indicate that dietary supplementation of COS at 400 or 600 mg/kg promotes growth performance and improves gut barrier function, increases the population of Bifidobacteria and Lactobacilli, and decreases S. aureus in the cecum of weanling pigs.

Vitrification of boer goat morulae and early blastocysts by straw and open-pulled straw method.

The aim of this study was to investigate the effects of different vitrification solutions [EFS30 or EFS40 contains 30% (v/v) ethylene glycol (EG), 40% (v/v) EG; EDFS30 or EDFS40 contains 15% (v/v) EG and 15% (v/v) dimethyl sulfoxide (DMSO), 20% (v/v) EG and 20% (v/v) DMSO], equilibrium time during vitrification (0.5-2.5 min) and vitrification protocols [one-step straw, two-step straw and open-pulled straw (OPS)] on in vivo development of vitrified Boer goat morulae and blastocysts after embryo transfer. In the one-step straw method, the lambing rates of vitrified embryos in EFS30 (37.5%), EFS40 (40.5%) or EDFS30 (38.2%) group were similar to that of fresh embryos (57.5%) and conventional freezing method (46.7%) when the equilibrium time was 2 min. In the two-step straw method, the highest lambing rate was obtained when embryos were pretreated with 10% EG for 5 min and then exposed to EFS40 for 2 min (51.4%), showing similar lambing rates compared with fresh embryos (56.1%) or the embryos cryopreserved by conventional freezing method (45.2%). In the OPS method, the lambing rate in EFS40, EDFS30 or EDFS40 groups were similar to that (57.1%) of fresh embryos, or to that (46.0%) of embryos cryopreserved by conventional freezing method. The highest lambing rate (51.4%) of the group of OPS was obtained when the embryos were vitrified with EDFS30. In conclusion, either the two-step straw method in which embryos were pretreated in 10% EG for 5 min and then exposed to EFS40 for 2 min, or the OPS method in which embryos were pretreated in 10% EG + 10% DMSO for 30 s and then exposed to EDFS30 for 25 s was a simple and efficient method for the vitrification of Boer goat morulae and blastocysts.

Effects of cysteamine on growth performance, digestive enzyme activities, and metabolic hormones in broilers.

A total of 600 avian male broilers at the age of 1 d were used to investigate the effects of cysteamine (CSH) on growth performance, digestive enzyme activities, and concentrations of serum hormones. The broilers received the same basal diets, with CSH added at 0 (control), 60, 90, 120, or 150 mg/kg. The feeding program consisted of a starter diet until 21 d and a grower diet until 42 d. The broilers with addition of CSH at 60 or 90 mg/kg had significantly higher growth rates during d 1 to 21 or d 21 to 42 compared with the control, respectively. However, adding 150 mg of CSH/kg significantly suppressed the growth of broilers. Adding 60 mg of CSH/kg significantly increased the activities of protease, amylase, and lipase in the pancreas and small intestinal contents during d 1 to 21, and the activities of protease and amylase in the small intestinal contents during d 21 to 42. Adding 90 mg of CSH/kg significantly increased the activities of lipase during d 1 to 21 and protease, amylase, and lipase during d 21 to 42 in small intestines. The activities of digestive enzymes during the whole period were suppressed by adding 150 mg of CSH/kg. The concentration of serum thyroxine was higher in the CSH-added birds during the whole period, whereas serum triiodothyronine was higher only during d 1 to 21 compared with the control. These findings indicate that low doses of dietary CSH may improve the growth performance and the activities of the digestive enzyme, but high doses of CSH appear to be detrimental to growth and digestion.

Bandwidth extension for IR detectors through spatial-frequency shifting.

We describe a new scheme for extending the bandwidth of IR detectors by the employment of a reticle that shifts the higher spatial-frequency content of the scene onto the lower-frequency region. Then all the spatial-frequency information can pass through the bandwidth of the detector system, so that a high-resolution image may be reconstructed from a series of pictures obtained with the reticle in a number of predetermined positions.

An improved median filter.

A modified median filtering technique offering improved smoothing performance while maintaining the edge-preserving ability of the conventional median filter is presented. It is shown how a mean filter outperforms a median filter in noise reduction except on or near the image boundaries. Along with the edge-preserving ability of the median filter, this observation forms the basis of the three-stage filtering algorithm which is described.