内蒙古山羊流产病毒的特性研究

1990－1992年从野外山羊流产的胎儿中分离到2株病毒。1994年又从野外自然流产的山羊胎盘中分离到1株病毒。用琼脂扩散试验做交叉反应，证明3株分离病毒属于同一种病毒。用FUDR抑制试验鉴定其核酸型为RNA，在电镜下为圆形颗粒，直径约60－70mm，其能在BHK21，Vero细胞上和鸡胚中增殖，产生明显的CPE。将其回归孕山羊，引起51．2％（21／41）流产。研制的福氏完全佐剂灭活苗初试与对照比较，可使流产降低46％，血清学反应证实其与BTV，IBARKIV，EHDV，AKBV无相关性。     

Potential Effects of Temperature on Early Reproductive Development and Progeny Performance in Picea abies (L.) Karst

In order to enhance cone production in Norway spruce [Picea abies (L.) Karst] seed orchards have been established in more southerly, warmer sites in Norway. This has led to concern and some evidence that seedlings obtained from parent trees grown at warmer sites may not be well adapted if planted in northern regions. Selective events during sexual reproduction in the warmer climate may select for traits not well adapted for cold climates. This study describes ovule and male gametophyte development, fertilization and proembryo and early embryo development under six different temperature regimens of warm or cold, warm-cold or cold-warm, and compares development in relation to temperature sums in degree days (dd) and calendar date. The outside treatment in a cold climate in Norway served as the control, and normal development and few ovule abortions and abnormalities were observed. In no treatments were abnormalities in male gametophyte development observed. In treatments in which trees were kept in the greenhouse throughout the study or moved during the study from the outside to inside the greenhouse, a higher incidence of megagametophyte, egg or embryo abortion was generally observed.     

核不育芝麻小孢子败育机理的细胞学研究

核不育芝麻小孢子败育发生在四分体形成之后的无液泡小孢子期,败育在很短的时间内完成。败育前小孢子大量液泡化,其线粒体异常膨大与质体的基质化可作为小孢子开始败育的标志。败育小孢子缺少花粉外壁上的覆盖层。芝麻花药绒毡层的异常,包括有机物贮量的降低;细胞内含物的异位分布及迅速减少与消失;不能及时或缺乏分泌胼胝质     

高粱A2型胞质在中国的研究与利用

高粱A2型质核互作雄性不育系是美国高粱育种家舍尔茨教授于1976年创制,1979年引入中国。它的细胞质来自埃塞俄比亚,细胞核产自印度。A2型不育性是由一对细胞核基因和细胞质基因共同作用。不育系的基因型是S2(ms2ms2),其保持系的基因型是F2(ms2ms2),恢复系的基因型是F2或S2(Ms2Ms2)。对A1型不育系恢复或保持,大多对A2型也恢复或保持,少数恢复系呈保持型,说明A2具有更广泛的保持源。温度是影响育性的主要因子,在自然条件下,A2不育系雌蕊败育轻或不败育,雄蕊遇高温可散出花粉,使不育系产生少量自交结实。A2型胞质主要农艺性状的杂种优势和配合力与A1胞质无明显差异。山西省农科院1987年育成了第一个在生产中可以利用的A2细胞质雄性不育系V4A,并组配出A2型杂交种——晋杂12。该杂交种于1997年获山西省科技进步二等奖。以A2V4为母本组配并经省级审定杂交种5个。因此,该不育系的创制,于1998年获国家发明三等奖。原四平市农科院,用A2TAM428与南133组配成四杂25号,于2002年获吉林省科技进步二等奖。吉林省农科院用A2型不育系培育出吉杂80、吉杂83、吉杂96、吉杂97,辽宁农科院育出辽杂10等在生产中大面积推广。文中讨论了非迈罗胞质的育性反应及利用问题。     

Percentage change on natural killer subsets of peripheral blood and decidua in between normal early pregnancy and spontaneous abortion

AIM: To determinate the percentage change on natural killer(NK) subsets of peripheral blood and decidua in between normal early pregnancy and spontaneous abortion. METHODS: Flow cytometry was used to detect the expression of CD56 and CD16 on lymphocytes of decidua and peripheral blood in normal early pregnancy and spontaneous abortion. RESULTS: In peripheral blood, the percentage of CD56⁺ of spontaneous abortion tended to decrease in comparison with normal early pregnancy, and the percentage of CD56⁺CD16⁺ in spontaneous abortion was significantly less than that in normal early pregnancy. The percentages of different natural killer subsets in decidua of spontaneous abortion were significantly lower than those in decidua of normal early pregnancy. CONCLUSION: The decrease of CD56⁺NK cells in decidua may be one of causes for abortion, the loss of CD56⁺ and CD56⁺CD16^+NKcells in peripheral blood could have a diagnostic value for spontaneous abortion.     

Seroprevalences for ovine enzootic abortion in Switzerland

Our aim was to assess the seroprevalence of Chlamydophila (Cd) abortus (Chlamydia psittaci serotype 1), denoted ovine enzootic abortion (OEA), in the Swiss sheep population. A competitive enzyme-linked immunosorbent assay (cELISA) was adapted for the investigation of pooled serum samples (pool approach) and receiver-operator characteristic (ROC) analysis was applied to define the cut-off of the pool approach. At a cut-off value of 30% inhibition, the flock-level pooled sensitivity and specificity were 92.9% and 97.6% when compared to classifying the flock based on individual-animal samples.

Subsequently, sera from 775 randomly selected flocks out of 11 cantons of Switzerland were investigated using the pool approach. The cantons included in the study represented 72% of the Swiss sheep flocks and 76% of Swiss sheep population. Antibodies against Cd. abortus were found in almost 19% (144) of the 775 examined sheep flocks. Test prevalences were adjusted for the imperfect test characteristics using the Rogan–Gladen estimator and Bayesian inference. Seroprevalence was highest (43%) in the canton Graubünden. In the remaining 10 cantons the seroprevalence ranged from 2 to 29%. The cELISA in combination with testing pooled sera and statistical methods for true prevalence estimation provided a good survey tool at lower costs and time when compared to other approaches.     

Detection of porcine circovirus genotypes 2a and 2b in aborted foetuses from infected swine herds in the State of S?o Paulo,Brazil

Background

Porcine circovirus type 2 (PCV2) has been associated with several disease complexes, including reproductive failure. The aim of this study was to identify the subtypes of PCV2 that are associated with reproductive failure in pigs from the State of São Paulo, Brazil and to investigate co-infections with other infectious organisms.

Findings

Samples of 168 aborted foetuses or mummified foetuses from five farrow-to-finish swine farms known to be infected with PCV2 and located in the State of São Paulo were tested for PCV2 by polymerase chain reaction (PCR). Positive samples were additionally tested for porcine parvovirus (PPV), Leptospira spp. and Brucella spp. by PCR. PCV2 was detected in 18 of the samples (10.7%). PPV, Brucella spp. and Leptospira spp were found in 2, 10 and 0 cases, respectively. Eleven PCV2 strains were sequenced and determined to be either genotype 2a (n = 1) or 2b (n = 10).

Conclusions

The findings indicate that the frequency of PCV2 infections in aborted porcine foetuses from the State of São Paulo is rather low (10.7%) and that co-infection with other pathogens is common and may be involved in PCV2 associated reproductive failure. No repeatable, characteristic amino acid motifs for regions of the PCV2 capsid protein seemed to be associated with abortion in sows.     

Factors Influencing the Frequency of Pregnancy Loss among Thoroughbred Mares in Hidaka,Japan

Pregnancy loss in mares is thought to be a main problem associated with reproductive efficiency. To clarify the situation of pregnancy loss in Thoroughbred mares in Japan, the occurrence of pregnancy loss before and after 35 days of gestation was investigated with 1,476 Thoroughbred mares in Hidaka, Japan, from 2007 to 2009. Pregnancy loss on days 17-35 was determined by ultrasound examination between 17 and 35 days after the last mating. Follow-up surveys were conducted between 35 days and foaling to determine pregnancy loss on day 35 until foaling in 843 of these mares. Using multiple logistic regression analysis, we assessed the influence of mare age, reproductive status, twin pregnancy reduction, body condition score (BCS), estrus type in foaling mares (foal heat or not), progesterone therapy, and endometrial cysts on pregnancy loss rates on days 17-35 and on day 35 until foaling in this population of mares. The pregnancy loss rates on days 17-35 and on day 35 until foaling were 5.8% and 8.7%, respectively. The overall pregnancy loss rate (day 17 until foaling, including parturient losses) was 14.7%. Risk factors for pregnancy loss included decrease in BCS between 17 and 35 days, <5 BCS at day 35, mating during foal heat, and endometrial cysts. In all, 14.7% of pregnancies were lost between day 17 and birth, contributing significantly to reduced reproductive efficiency in Thoroughbred mares in Japan. These observations indicate that mares should be maintained at high BCS and should be prevented from mating in foal heat to decrease the pregnancy loss rates.     

Bovine herpes virus-1 (BoHV-1) in cattle–a review with emphasis on reproductive impacts and the emergence of infection in Ireland and the United Kingdom

Bovine reproductive disease attributable to bovine herpes virus-1 (BoHV-1) was first described in Germany in the 19^th century, being recognised primarily as the cause of infectious vulvovaginitis and balanoposthitis until the mid-1950s when a more virulent strain of the virus (BoHV-1.1) associated with respiratory disease (infectious bovine rhinotracheitis; IBR) emerged in the western United States. Subsequently, IBR emerged as a clinical condition in Europe, from the 1970s onward. While the ability of BoHV-1 to produce respiratory disease is now well recognised, the potential negative outcomes of infection on fertility and reproduction are less frequently considered. This review was conducted against the background of the prioritization of disease caused by BoHV-1 as one of several diseases to be addressed by Animal Health Ireland, with the twin goals of summarizing the published literature on the potential outcomes of infection at different stages of breeding and pregnancy, and of describing the emergence of BoHV-1 as a significant pathogen in Ireland and the UK.