Genetic diversity and selection signatures in Hainan black goats revealed by whole-genome sequencing data.

Understanding the genetic characteristics of indigenous goat breeds is crucial for their conservation and breeding efforts. Hainan black goats, as a native breed of south China's tropical island province of Hainan, possess distinctive traits such as black hair, a moderate growth rate, good meat quality, and small body size. However, they exhibit exceptional resilience to rough feeding conditions, possess high-quality meat, and show remarkable resistance to stress and heat. In this study, we resequenced the whole genome of Hainan black goats to study the economic traits and genetic basis of these goats, we leveraged whole-genome sequencing data from 33 Hainan black goats to analyze single nucleotide polymorphism (SNP) density, Runs of homozygosity (ROH), Integrated Haplotype Score (iHS), effective population size (Ne), Nucleotide diversity Analysis (Pi) and selection characteristics. Our findings revealed that Hainan black goats harbor a substantial degree of genetic variation, with a total of 23 608 983 SNPs identified. Analysis of ROHs identified 53 710 segments, predominantly composed of short fragments, with inbreeding events mainly occurring in ancient ancestors, the estimates of inbreeding based on ROH in Hainan black goats typically exhibit moderate values ranging from 0.107 to 0.186. This is primarily attributed to significant declines in the effective population size over recent generations. Moreover, we identified 921 candidate genes within the intersection candidate region of ROH and iHS. Several of these genes are associated with crucial traits such as immunity (PTPRC, HYAL1, HYAL2, HYAL3, CENPE and PKN1), heat tolerance (GNG2, MAPK8, CAPN2, SLC1A1 and LEPR), meat quality (ACOX1, SSTR1, CAMK2B, PPP2CA and PGM1), cashmere production (AKT4, CHRM2, OXTR, AKT3, HMCN1 and CDK19), and stress resistance (TLR2, IFI44, ENPP1, STK3 and NFATC1). The presence of these genes may be attributed to the genetic adaptation of Hainan black goats to local climate conditions. The insights gained from this study provide valuable references and a solid foundation for the preservation, breeding, and utilization of Hainan black goats and their valuable genetic resources.

Lowering storage temperature during ovary transport is beneficial to the developmental competence of bovine oocytes used for somatic cell nuclear transfer.

The objective of this study was to determine the effect of storage temperature during ovary transport on the developmental competence of bovine oocytes for use in somatic cell nuclear transfer (SCNT). Ovaries obtained from a slaughterhouse were stored in physiological saline for 3-4h at one of the three temperatures: 15 °C, 25 °C, or 35 °C. The developmental competence of oocytes used for SCNT was ascertained by cleavage and blastocyst formation rate, total cell number, apoptosis index, and the relative abundance of Bax and Hsp70.1 in day 7 blastocysts. Ovaries stored at 35 °C for 3-4h reduced the recovery rate of grade I and II oocytes compared with those stored at 25 °C or 15 °C (45.1±0.7% vs. 76.7±1.2% or 74.8±2.0%, P<0.05). The proportion of oocytes matured to the MII stage (maturation rate) for oocytes stored at 35 °C was significantly lower than those stored at 25 °C or 15 °C (51.3±0.9% vs. 75.1±1.4% or 71.7±1.3%, P<0.05). Cleavage rate (77.7±2.1%, 77.9±1.1% and 72.1±0.7% for 15 °C, 25 °C and 35 °C groups, respectively) and blastocyst formation rate (39.1±0.5%, 36.8±1.4% and 32.2±0.9% for 15 °C, 25 °C and 35 °C groups, respectively) following SCNT were not significantly different between treatments. Oocytes from ovaries stored at 15 °C, however, produced blastocysts with higher cell numbers (97.3±8.6 vs. 80.2±10.8 or 77.4±11.7; P<0.05) and lower apoptotic index (5.1±1.3 vs. 13.5±1.6 or 18.6±1.1, P<0.05) than those stored at 25 °C or 35 °C. The relative abundance of Bax and Hsp70.1 in day 7 blastocysts produced from oocytes derived from ovaries stored at 15 °C was lower than those stored at 25 °C or 35 °C (P<0.05). It was concluded that a storage temperature of 15 °C for a 3-4h period had a significant beneficial effect on the quality and developmental competence of oocytes used for SCNT due to the alleviation of stresses on the oocytes compared with those subjected to storage temperatures of 25 °C or 35 °C.

Production of cloned calves by combination treatment of both donor cells and early cloned embryos with 5-aza-2/-deoxycytidine and trichostatin A.

We previously reported that treatment of both donor cells and early cloned embryos with a combination of 0.01 µM 5-aza-2(/)-Deoxycytidine (5-aza-dC) and 0.05 µM trichostatin A (TSA) significantly improved development of cloned bovine embryos in vitro. In the present study, we investigated the effect of this combination treatment on the in vivo development potency and postnatal survivability of cloned calves. Blastocysts (77 and 82 blastocysts derived from untreated (control) and treated groups, respectively) were individually transferred to recipient cows. Relative to the control group, the combination treatment of both donor cells and early embryos with 5-aza-dC and TSA dramatically increased the cleavage rate (49.2 vs 63.6%, P < 0.05) at 24 h of culture, and blastocyst development rate on Days 6 and 7 of culture (18.8 vs 33.9% and 27.1 vs 38.5% respectively, P < 0.05). Although pregnancy rate did not differ 40 d after transfer, it was lower in the treated than control group 90 d after transfer (7.8 vs 29.3%, P < 0.05). In the control group, there were three calves born to 77 recipients (only two survived beyond 60 d), whereas in the treated group, 17 calves were born to 82 recipients, and 11 survived beyond 60 d. In conclusion, a combination treatment of donor cells and early cloned embryos with 5-aza-dC and TSA significantly enhanced development of somatic cell cloned bovine embryos in vivo; cloning efficiency (number of surviving calves at 60 d of birth/number of recipient cows) was increased from 2.6 to 13.4%.

Effect of mSOF and G1.1/G2.2 media on the developmental competence of SCNT-derived bovine embryos.

The objective of this study was to compare the effect of two culture media: modified synthetic oviductal fluid (mSOF) and G1.2/G2.2, on the developmental competence of bovine somatic cell-cloned embryos. Cloned embryos were produced by transferring adult skin fibroblasts into enucleated MII oocytes. After activation, the reconstructed embryos were randomly allotted to either mSOF or G1.2/G2.2 for culture (the embryos were transferred from G1.2 to G2.2 on days 3 of culture). The development competence of cloned embryos in these two culture systems was compared in terms of cleavage rate, blastocyst formation rate and apoptosis cell number in day 7 blastocyts. To investigate the in vivo developmental competence of cloned embryos in the two culture systems, a total of 87 and 104 blastocysts derived from mSOF and G1.2/G2.2 medium groups were transferred individually to recipient Angus cows, respectively. No differences were observed in terms of cleavage rate, day 7 blastocyst rate and blastocyst cell number between these two culture systems. However, the day 6 blastocyst formation rate was significantly higher in G1.2/G2.2 than that in mSOF. In addition, blastocysts cultured in mSOF have a higher percentage of apoptotic blastomeres compared to those in G1.2/G2.2 (8.5 ± 1.2 vs 16.8 ± 1.5, p<0.05). Although difference in pregnancy rate was not observed 40 days after embryo transfer, significantly higher pregnancy rate was observed in G1.2/G2.2 group after 90 days of embryo transfer (12.4% vs 37.5%, p<0.05). Moreover, calving rate was significantly improved in G1.2/G2.2 group compared to mSOF group (27.9% vs 6.7%, p<0.05). In conclusion, our results indicate that G1.2/G2.2 can improve developmental competence of bovine SCNT embryos both in vitro and in vivo, which is more suitable for culture of bovine SCNT embryos than mSOF medium.

Neurogenic differentiation of EGFP gene transfected amniotic fluid-derived stem cells from pigs at intermediate and late gestational ages.

The aims of this study were (i) to determine whether amniotic fluid-derived stem cells (amniotic fluid-derived stem; AFS cells) could be isolated from pigs at intermediate and late gestational ages, and (ii) to determine if these AFS cells could be differentiated in vitro into neural lineages following transfection with a reporter gene, enhanced green fluorescence protein (EGFP). Amniotic fluid-derived stem cells were isolated from embryonic day 60 and day 110 porcine amniotic fluid respectively, and transfected with EGFP gene using lipofection. The transfected AFS cells were induced to differentiate into cells of neuronal lineages. Markers associated with undifferentiated AFS cells and their neural derivatives were tested by polymerase chain reaction. The results demonstrated that porcine AFS cells could be isolated at intermediate and late gestational ages and that transfected AFS expressed EGFP and could be induced to differentiate in vitro. Undifferentiated AFS cells expressed POU5F1, THY1 and SOX2, while following differentiation cells expressed markers for astrocytes (GFAP), oligodendrocytes (GALC) and neurons (NF, ENOS and MAP2).

Codeposition of dNTPs detection for rapid LAMP-based sexing of bovine embryos.

Loop-mediated isothermal amplification (LAMP) is a novel nucleic acid amplification method with high specificity and rapidity under isothermal conditions. According to the LAMP method, a rapid and simple detection system was established for bovine embryo sexing. Two sets of primers were designed by targeting the bovine male-specific sequence and bovine common sequence respectively. The reaction condition of the detection system was optimized within 60 min under isothermal conditions of 65 degrees C by detection of the reaction mixture on agarose gel. Especially, the primers F2 and B2 could replace the F3 and B3 as outer primers, making the primer design simpler and the amplification efficiency higher. Additionally, codeposition of dNTPs was firstly performed to detect the reaction products by addition of 1 microl 0.1 mM CuSO(4), the visible ring-shaped deposit was found in the middle of the reaction tube with negative mixture. It could be employed as an alternative method in the detection of the reaction products in place of the time-consuming electrophoresis or the turbidity meter. Furthermore, the embryo sexing system was carried out in the embryo transfer and achieved 98% of efficiency and 99.5% of accuracy.

Effects of diet and exercise in preventing NIDDM in people with impaired glucose tolerance. The Da Qing IGT and Diabetes Study.

OBJECTIVE: Individuals with impaired glucose tolerance (IGT) have a high risk of developing NIDDM. The purpose of this study was to determine whether diet and exercise interventions in those with IGT may delay the development of NIDDM, i.e., reduce the incidence of NIDDM, and thereby reduce the overall incidence of diabetic complications, such as cardiovascular, renal, and retinal disease, and the excess mortality attributable to these complications. RESEARCH DESIGN AND METHODS: In 1986, 110,660 men and women from 33 health care clinics in the city of Da Qing, China, were screened for IGT and NIDDM. Of these individuals, 577 were classified (using World Health Organization criteria) as having IGT. Subjects were randomized by clinic into a clinical trial, either to a control group or to one of three active treatment groups: diet only, exercise only, or diet plus exercise. Follow-up evaluation examinations were conducted at 2-year intervals over a 6-year period to identify subjects who developed NIDDM. Cox's proportional hazard analysis was used to determine if the incidence of NIDDM varied by treatment assignment. RESULTS: The cumulative incidence of diabetes at 6 years was 67.7% (95% CI, 59.8-75.2) in the control group compared with 43.8% (95% CI, 35.5-52.3) in the diet group, 41.1% (95% CI, 33.4-49.4) in the exercise group, and 46.0% (95% CI, 37.3-54.7) in the diet-plus-exercise group (P < 0.05). When analyzed by clinic, each of the active intervention groups differed significantly from the control clinics (P < 0.05). The relative decrease in rate of development of diabetes in the active treatment groups was similar when subjects were stratified as lean or overweight (BMI < or > or = 25 kg/m2). In a proportional hazards analysis adjusted for differences in baseline BMI and fasting glucose, the diet, exercise, and diet-plus-exercise interventions were associated with 31% (P < 0.03), 46% (P < 0.0005), and 42% (P < 0.005) reductions in risk of developing diabetes, respectively. CONCLUSIONS: Diet and/or exercise interventions led to a significant decrease in the incidence of diabetes over a 6-year period among those with IGT.