Post-thawing Sperm Quality in Chilean Purebred Stallions: Effect of Age and Seasonality

In this work, we investigated the influence of age and seasonality on sperm motility and DNA fragmentation in post-thawing semen from Chilean Purebred Stallions (CPS), a horse breed presenting the oldest genealogy record in South America with an interesting reproductive industry. Despite that semen from aged CPS is frozen all year round, there is a lack of studies characterizing the breed semen freezability in accordance with age and seasonality. Twenty fertile CPS were grouped into the young group, the middle group, and the aged group. Ten ejaculates from each stallion were obtained by using an artificial vagina during summer (December) and winter (July) and directly frozen. Subsequently, the frozen semen was thawed and analyzed by a computer-assisted semen analysis and flow cytometer assessing progressive motility, mean velocity, and DNA fragmentation spermatozoa. Kruskal–Wallis test and Pearson’s correlation were used to determine statistical differences among groups and correlation among variables (P ≤ .05). Both spermatozoa motility traits decreased progressively in accordance with age and seasonality, showing the lowest values in the aged group during winter and the highest values in the young group during summer. Deoxyribonucleic acid fragmentation increased significantly in accordance with age and seasonality being highest in the aged group during winter and lowest in the young group during summer. Post-thawing sperm quality showed a negative correlation with the age of the stallions and a positive correlation with the normal sperm morphology before freezing. These results allow the conclusion that age and seasonality are important factors that need to be considered during the selection of CPS for reproductive programs.     

西方蜜蜂不同蜂种及其正反交组合采胶力研究

“浙农大 1号”意蜂 (简称Ea)分别与喀尼鄂拉蜂 (简称K)、卡尔巴阡蜂 (简称C)、高加索蜂 (简称G)、乌克兰蜂 (简称W )、东北黑蜂 (简称D)进行正反杂交组配。在山东荆条场地 ,考察这 6个西方蜜蜂蜂种及 10个正反杂交组合的 15 0个试验蜂群的蜂胶生产性能 ,分析杂交一代的杂种优势。结果表明 :Ea是六个纯种中蜂胶产量最高的蜂种 ,Ea×C是所有纯种和杂交组合中蜂胶产量最高的蜂种 ,是培育蜂胶高产杂交组合的首选蜂种 ,其他 9个杂交组合均未表现出杂种优势     

Estimation of genetic parameters on test stations using purebred and crossbred progeny of sires of the Bavarian Piétrain

Genetic parameters were estimated for purebred and crossbred progeny of Bavarian Piétrain sires on two test stations. The data set used contained 4276 purebred pigs and 13,980 crossbred pigs recorded between 2000 and 2004. In total 332 sires having purebred and crossbred progeny were available to estimate the genetic correlations between purebred and crossbred performances. Though the genetic correlations between purebred and crossbred pigs are fairly high (0.7–0.9), their performances have to be considered as genetically different traits, because variance components and heritabilities differ substantially. Therefore, purebred and crossbred breeding values of candidates are not identical, and thus result in different rankings. However, due to the high correlations purebred pigs provide a lot of information for estimating the crossbred breeding values of the real selection criterion. The Halothan locus, whose effects have been analyzed in detail, affects both purebred and crossbred parameters. To avoid detrimental effects on the efficiency of the breeding programme, the n-allele could be either eliminated or the genotypes of all test animals should be known. Differences in the variance components between the two test stations have been found and are problematic with respect to the breeding value estimation utilizing the pooled data set. Hence, it should be attempted to further improve the standardization of the performance test on both stations.     

Age- and Sex-Related Modifications of Hematology in Spanish Purebred Horse

The purpose of this study was to test the hypothesis that age and sex significantly modulate the changes in hematological parameters of physiologically healthy Spanish Purebred horse, establishing the reference values. Blood samples were obtained on a total of 159 horses (n = 77 males and n = 82 females), classified in four age groups: group A (1–2 years; n = 39), group B (>2–3 years; n = 38), group C (>3–4 years; n = 41), and group D (>4–7 years; n = 41). By means ADVIA 2020i, red blood cell (RBC), hemoglobin concentration (HB), packed cell volume, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration, platelets (PLTs), as well as total and differential white blood cells (WBCs) were determined. Total plasma protein was determined by spectrophotometry. Results obtained showed that sex had a limited influence on these parameters, being the HB higher in males and WBC higher in females (P = .047). Age caused a reduction in RBC, with a compensatory increase of MCV and MCH, decrease in WBC, PLT, lymphocytes (LYMPs), as well as an increase of N/L ratio (P = .047). Interactions between age and sex showed higher RBC in males than in females of the group B, and higher HB and WBC in males than in females of the group D. According to hematological data, Spanish Purebred horse was classified as a warm- or cold-blooded horse. Decline of RBC, WBC, and PLT parameters is a natural condition of horse with the advance of age, indicating a decrease of the narrow bone response.     

杂种鹅肥肝生产性能研究

选用同批自行孵化、育雏、肥育的１１０日龄朗德鹅、莱茵鹅、丰城灰鹅及朗莱、朗丰、莱朗、菜丰杂交一代肉用仔鹅，在５月阴雨季节，经２５天强制填肥，平均肥肝重分别为５１８．３３、２８８．３３、２９５．００、３９２．５０、３６２．５０、４７３．３３、２８７．５０ｇ，料肝比相应为２７．５９：１、４８．２３：１、４５．７８：１，３６．７５：１、３９．２７：１、２９．２９：１和４９．６１：１。结果表明，朗德鹅、莱朗杂交一代肉鹅是肥肝生产的理想品种（组合）。朗莱、朗丰杂交一代肉鹅均可作为大规模肥肝生产品种（组合）。     

小孢毛鬼伞驯化研究初报

小孢毛鬼伞(Coprinus ovatus),1987年采于呼和浩特市南郊开阔的农田和荒地上.该菇经分离培养获得了纯菌种,在 PDA.麸皮等培养基上生长良好,并采用麦秸等为主料进行栽培获得了子实体。子实体未开伞前菌盖呈卵形至棒锤形,白色,其形成以19℃最为适宜;空气相对湿度须在75%～95%之间;光线强度在10～100LX 之间,空气中 CO_2浓度在0.1%以下均能正常结菇。