Semi-fine Wool Research Articles

Effects of the Tris, Tes, or skim milk based extender on in vitro parameters of ram spermatozoa during liquid storage

Cryopreservation can seriously damage structure and physiological function of mammalian spermatozoa. However, liquid storage at reduced temperature may be an alternative of cryopreservation if artificial insemination is performed in relatively short time. In this study, effects of the Tris-hydroxymethyl aminomethane (Tris), N-Tris (hydroxymethyl) -methylaminoethane-sulfonic acid (Tes), or skim milk based extender on ram spermatozoa during liquid storage at 4°C were assessed and compared. Semen samples from 6 adult Yunnan semi-fine wool rams with proven fertility were pooled, equally divided into 3 groups according to extenders, and preserved at 4°C for various durations (0, 1, 3, 5, and 7 days). The motility, moving velocity, and hypo-osmotic swelling capability of spermatozoa were evaluated using a computer assisted sperm analyzer system. The acrosome status, membrane integrity, distribution of phosphatidylserine (PS), and mitochondrial membrane potential (MMP) were analyzed with flow cytometry. The results indicated that following liquid storage in the Tris or Tes based extender for 3 days, the motility, hypo-osmotic swelling capability, and MMP of spermatozoa did not show a significant decrease. Additionally, liquid storage in the Tris or Tes based extender for 24h did not deleteriously affect the moving velocity, acrosome status, and membrane integrity of spermatozoa. However, after liquid storage for 24h, the percentage of spermatozoa with membrane exposed PS was significantly increased. On the contrary, the negative effects of skim milk on the above parameters of ram spermatozoa became more serious compared to the Tris or Tes based extender after liquid storage for 24h (P<0.05). There was no significant difference existing between the Tris and Tes based extender as concerning the parameters evaluated in this study. In conclusion, the Tris or Tes based extender may be more suitable for liquid storage of ram spermatozoa at reduced temperature compared to the skim milk based extender. Tris can be substituted by Tes for liquid storage of ram semen. The future study should focus on assessment of molecular changes and fertility of ram spermatozoa after liquid storage.

Cryopreservation of ram spermatozoa in the presence of cyclohexanhexol-derived synthetic ice blocker

The effects of cyclohexanhexol-derived synthetic ice blockers (SIBs) including 1,3-cyclohexanediol (1,3-CHD) and 1,4-cyclohexanediol (1,4-CHD) on chilled or frozen Yunnan semi-fine wool ram spermatozoa were systematically assessed and compared in this study. The collected semen was pooled and equally divided into two parts. In the first part, in order to evaluate the effect of SIBs on chilled spermatozoa before freezing, the semen was divided into nine groups according to the concentrations of SIBs (0, 25mM, 50mM, 100mM, or 200mM). In the second part, the treatment of semen was similar to the first part. However, except for the cooling and equilibrating procedures, spermatozoa were preserved in liquid nitrogen for one month. Motility, moving velocity, acrosome status, membrane integrity, and mitochondrial membrane potential (MMP) of frozen/thawed spermatozoa were determined using a computer-assisted spermatozoa analysis system (CASAS), fluorescence staining, and flow cytometry. The data indicated that when the concentrations of SIBs were less than or equal to 100mM, there is no significant difference among the treating groups as concern spermatozoa motility and moving velocity following equilibration at 5°C. However, when the concentrations of SIBs were increased to 200mM, the motility and moving velocity of chilled ram spermatozoa were significantly decreased compared to the control spermatozoa (P<0.05). With elevation of the SIB concentrations, the motility of frozen/thawed spermatozoa was firstly increased and then reduced. With a concentration of 50mM or 100mM, the spermatozoa motility was approximately 50% and significantly more than the other groups (P<0.05). Additionally, when the SIB concentrations were less than or equal to 100mM, there is no significant difference between the treating groups as concern moving velocity. Moreover, when the concentration of 1,3-CHD or 1,4-CHD was 100mM, the percentage of frozen/thawed ram spermatozoa with intact acrosome was 82.57±8.97% and 79.51±13.49% respectively, which were significantly higher than that of the control spermatozoa (70.21±13.24%, P<0.05). Additionally, with elevation of the SIB concentrations, the percentages of frozen/thawed ram spermatozoa with damaged membrane showed a steady increase. Finally, the presence of 100mM SIBs can significantly improve the MMP status of frozen/thawed ram spermatozoa compared to spermatozoa frozen in the absence of SIBs. In conclusion, SIBs can improve the viability of frozen/thawed ram spermatozoa as concern motility, acrosome status, and MMP. However, SIBs cannot improve moving velocity and membrane integrity of frozen/thawed spermatozoa. Finally, the protective effect of 1,3-CHD is not superior to that of 1,4-CHD on chilled or frozen ram spermatozoa.

Phosphorus metabolic disorder of Guizhou semi-fine wool sheep.

Guizhou semi-fine wool sheep are affected by a disease, characterized by emaciation, lameness, stiffness in the gait, enlargement of the costochondral junctions, and abnormal curvature in the long bones. The objective of this study was to determine possible relationships between the disease and mineral deficiencies. Samples of tissue and blood were collected from affected and unaffected sheep. Samples of soil and forage were collected from affected and unaffected areas. The samples were used for biochemical analyses and mineral nutrient measurements. Results showed that phosphorus (P) concentrations in forage samples from affected areas were significantly lower than those from unaffected areas (P < 0.01) and the mean ratio of calcium (Ca) to P in the affected forage was 12:1. Meanwhile, P concentrations of blood, bone, tooth, and wool from the affected sheep were also significantly lower than those from the unaffected group (P < 0.01). Serum P levels of the affected animals were much lower than those of the unaffected ones, whereas serum alkaline phosphatase levels from the affected were significantly higher than those from the unaffected (P < 0.01). Inorganic P levels of the affected sheep were about half of those in the control group. Oral administration of disodium hydrogen phosphate prevented and cured the disease. The study clearly demonstrated that the disease of Guizhou semi-fine wool sheep was mainly caused by the P deficiency in forage, as a result of fenced pasture and animal habitat fragmentation.

Polymorphism of BMP2 Gene Associated with Growth Traits in Guizhou Semi-Fine Wool Sheep

Polymorphism of BMP2 Gene Associated with Growth Traits in Guizhou Semi-Fine Wool Sheep

Copper deficiency in Guizhou semi-fine wool sheep on pasture in south west China karst mountain area

The Guizhou semi-fine sheep in the Weining County, Guizhou province, south west China karst mountain area were affected by an ailment characterized by pica, emaciation, dyskinesia, depressed appetites, unsteady gait and anemia. We found that concentrations of copper (Cu) in soil and forage from affected and unaffected areas were within the normal ranges, but concentrations of sulfur (S) and molybdenum (Mo) in soil and forage were significantly higher (P<0.01) in affected areas than in unaffected areas. Concentrations of Cu in blood, wool and liver from the affected Guizhou semi-fine sheep were significantly lower (P<0.01) than those in healthy animals. Affected Guizhou semi-fine sheep showed a hypochromic microcytic anemia and a low level of ceruloplasmin. Oral administration of CuSO 4 prevented and cured the disease. We conclude that the disorder of Guizhou semi-fine sheep is caused by secondary Cu deficiency, mainly due to high S and Mo content in forage.

Studies on Wool-Eating Ailment in Guizhou Semi-Fine Wool Sheep

Abstract The clinical symptoms of a disorder which is known locally as “wool-eating ailment” in Guizhou semi-fine wool sheep in the Weining County of Guizhou Province, China, are poor weight gain, lost appetite, pica, emaciation, and wool-eating. The mineral composition of forage, and samples of blood, liver and wool from Guizhou semi-fine wool sheep in affected ranches were compared with those from the unaffected areas. The mean concentration of iron in forage from affected pasture was significantly higher than that from the unaffected pasture. The mean concentration of sulfur in forage from the affected and unaffected pasture was similar and within normal ranges. The mean concentration of sulfur in blood, liver and wool from the affected Guizhou semi-fine wool sheep was significantly lower than that from the unaffected sheep while the content of iron in blood, liver and wool from the affected sheep was significantly higher than that from the unaffected sheep. Oral administration of calcium sulfate prevented and cured the disease. We concluded that the disease of Guizhou semi-fine wool sheep in the Weining County is due to S deficiency caused by the high Fe in forages.

Analysis of the fractal properties of the birth weight of Liangshan semi-fine wool sheep

Understanding of animal population genetic structure about quantitative traits is an important step in animal breeding. In the present study, the data of birth weight of the Liangshan semi-fine wool sheep was first studied by the fractal theory of nonlinear theory. The information dimension, correlation dimension, none-scale range, and the scale range were calculated. The results showed that (1) the information dimensions of the birth weight from 1996 to 2004 ranged from 0.66529 to 0.90675. The none-scale range and the range of the variation were very large. This indicates that the population had large dimensions of the BW (birth weight), large variation, and great potential in breeding; (2) the correlation dimensions ranged from 0.62438 to 0.86528, which indicates that the genetic structures of the population were highly correlated; (3) both of the two dimensions could reveal the fractal properties of the population genetic structure through two different aspects, and it was useful in studying the population genetic structure and animal breeding.

Correlation Analysis of Microsatellite DNA Markers with Wool Traits in Liangshan Semi-fine Wool Sheep

Eighteen microsatellites on chromosomes 1, 2, 3, 9 were studied to detect their genotypes in 206 individuals in a Liangshan Semi-fine Wool Sheep nucleus breeding population. A GLM procedure was used to analyze the effects of these 18 microsatellites on wool traits. Results uncovered 7 loci that had a significant impact on wool traits. Genotypes of that favorably affect wool traits were determined.