A comparison of the reduction in immunoglobulin (IgG) concentration of frozen equine plasma treated by three thawing techniques

SUMMARY: The IgG concentration of plasma from 13 mares was measured by radial immunodiffusion when fresh and after storage at -4°C and thawing by 3 methods. There was no significant (P > 0.05) reduction in the IgG concentration when plasma was thawed over 6 hours at 22°C (1352.9 ± 101.6 mg/dL) (mean ± SEM) compared with the fresh sample (1369.5 ± 88.1 mg/dL). In contrast, there was a significant (P < 0.05) reduction in the IgG concentration of plasma that was rapidly thawed at 57°C over 50 minutes (1142.9 ±66.2 mg/dL), or placed in a microwave oven for 20 to 25 minutes (1093.4 ± 74.4 mg/dL). When plasma is administered to hypo-gammaglobulinaemic newborn foals, a larger volume is required when thawing is rapid than when thawing is slow or when fresh plasma is administered.     

Systemic Immunosuppression by Methylprednisolone and Pregnancy Rates in Goats Undergoing the Transfer of Cloned Embryos

The presence of the zona pellucida has been perceived as a requirement for the oviductal transfer of cloned embryos at early stages of development while protecting the embryo from an immune system response. We hypothesized that steroid hormone therapy could reduce a potential cellular immune response after the transfer of zona‐free cloned embryos into the oviduct of recipient female goats. In Experiment 1, seven does were used to study the systemic immunosuppressant effect of the methylprednisolone administration (for 3 days) on blood cell counts. Whole blood was collected prior to treatment with methyprednisolone and then on Days 1, 2, 3, 4, 7, 14, 21 and 28 after the first dose of methylprednisolone for the analysis of haematological parameters. Methylprednisolone treatment significantly reduced circulating white blood cells and neutrophils in comparison with pre‐treatment levels, demonstrating a systemic immunosuppressant effect. In Experiment 2, a group of 58 does were used as recipient females to study the effect of administration of methylprednisolone for 3 days on the establishment of pregnancies after the transfer of zona‐free cloned embryos into the oviducts. No effects on pregnancy rates on Day 30 were observed regarding the distinct treatment groups (control vs. methylprednisolone), the source of oocytes (in vivo‐ vs in vitro‐matured) or the presence or absence of the zona pellucida in embryos. In summary, methylprednisolone was effective at inducing a systemic immunosuppressed state in goats, but the treatment prior to embryo transfer did not affect pregnancy rates. Moreover, pregnancy rates were similar between zona‐free and zona‐intact goat cloned embryos.     

Anomalous Pregnancies during Late Embryonic/Early Foetal Period in High Producing Dairy Cows

This study analyses anomalous cases of gestation ending in pregnancy loss during the early foetal period and their effect on progesterone and plasma pregnancy-associated glycoprotein-1 (PAG-1) concentrations. Data derived from a large-scale ultrasound pregnancy diagnosis programme in high producing dairy cows. Over a 3-year period (2004–2007), a very low incidence (0.5%: 15 of 3094) of anomalous pregnancies was recorded. The results revealed that the following anomalies were detected on days 35–41 of gestation in cows carrying singletons with one single corpus luteum: embryo death in eight cows (0.3%); and embryo in the uterine horn contralateral to the corpus luteum in seven cows (0.2%). All these animals suffered pregnancy loss during the early foetal period. In cows carrying dead embryos, no signs of conceptus degeneration were observed on pregnancy diagnosis. Amnion size (approximately 25 mm diameter) and uterine horn fluid contents were estimated to be similar to those of the normal pregnant cows in this period. In the contralateral gestations, live embryos were observed in all ultrasound checks before pregnancy loss. Uterine fluid contents increased in the two cows in which gestation continued for more than a week. In the cases of embryo death but not in those of contralateral gestation, a drop in PAG-1 levels was noted prior to pregnancy loss. Two cows carrying dead embryos increased with time allantoic fluid contents. The PAG-1 values increased with time in one cow bearing a dead embryo (from 2.31 to 6.79 ng/ml) and in two of the contralateral gestations (from 1.66 to 2.33 ng/ml and from 0.39 to 6.79 ng/ml, respectively). Results of this study indicate that the foetal membranes continue to undergo some activity following embryo death, and that contralateral pregnancy may determine failure of the gestation process.     

Magnetic Field and Plasma Observations at Mars: Initial Results of the Mars Global Surveyor Mission

The magnetometer and electron reflectometer investigation (MAG/ER) on the Mars Global Surveyor spacecraft has obtained magnetic field and plasma observations throughout the near-Mars environment, from beyond the influence of Mars to just above the surface (at an altitude of approximately 100 kilometers). The solar wind interaction with Mars is in many ways similar to that at Venus and at an active comet, that is, primarily an ionospheric-atmospheric interaction. No significant planetary magnetic field of global scale has been detected to date (<2 x 10(21) Gauss-cubic centimeter), but here the discovery of multiple magnetic anomalies of small spatial scale in the crust of Mars is reported.     

Equine neonatal septicaemia: 24 cases

Equine neonatal septicaemia was confirmed in 24 foals hospitalised at the Rural Veterinary Centre between 1989 and 1992 with suspected septicaemia. Septicaemia was confirmed by culture of bacteria from blood of live foals and tissues obtained at necropsy of foals that died or were euthanased. Pathogenic bacteria isolated were predominantly Enterobacteriaceae (including Escherichia coli and Salmonella serovars) and Actinobacillus equuli. Clinical manifestations of septicaemia included signs of depression, dehydration, abnormalities in body temperature and manifestations of localised infection including diarrhoea, pneumonia, and septic arthritis. Most common haemato-logical abnormalities were neutropenia and increase of circulating band neutrophils. Survival rate of foals with confirmed septicaemia was 70.8%. Survival was found to be less likely in the presence of pneumonia, severe signs of depression, marked haematological changes or septic arthritis at the time of admission. Seven foals were confirmed to have septic arthritis without concurrent septicaemia. Of these, 4 had multiple joint involvement. Bacteria isolated from infected joints were predominantly Salmonella serovars. Four foals with septic arthritis failed to survive, due to multiple joint infection, which was unresponsive to treatment. The clinical and haematological abnormalities present in foals with confirmed septicaemia and septic arthritis were consistent with those observed in other studies. The bacterial isolates from foals with confirmed septicaemia were similar to those isolated in other studies. In contrast, the bacteria isolated from foals with septic arthritis without concurrent septicaemia were different from other studies.     

群养鸡谨防痢菌净中毒

痢菌净学名乙酰甲喹,是我国研制的具有自主知识产权的兽用抗菌药品.本品抗菌谱广,不易产生抗药性,价格低廉,在畜牧养殖业上应用广泛.但在使用过程中常因超剂量应用导致中毒现象发生,造成不应有的损失.本文从药品特性、中毒症状、剖检变化、治疗、中毒原因分析等五个方面对群养鸡痢菌净中毒做了详尽阐述,以期基层兽医临床工作者有所借签.     

Processes controlling retention of spring‐spawned Atlantic cod (Gadus morhua) in the western Gulf of Maine and their relationship to an index of recruitment success

Atlantic cod, Gadus morhua, harvested in US waters are currently managed as a Gulf of Maine stock and as a stock comprising Georges Bank and southern New England populations. Over the past two and a half decades, success of age‐1 recruitment to the Gulf of Maine stock has varied by more than an order of magnitude. To investigate the hypothesis that this variation is related to variation in the transport of larval cod to nursery areas, we carried out model simulations of the movement of planktonic eggs and larvae spawned within the western Gulf of Maine during spring spawning events of 1995–2005. Results indicate that the retention of spring‐spawned cod, and their transport to areas suitable for early stage juvenile development, is strongly dependent on local wind conditions. Larval cod retention is favored during times of downwelling‐favorable winds and is least likely during times of upwelling‐favorable winds, during which buoyant eggs and early stage larvae tend to be advected offshore to the Western Maine Coastal Current and subsequently carried out of the Gulf of Maine. Model results also indicate that diel vertical migration of later stage larvae enhances the likelihood of retention within the western Gulf of Maine. Consistent with model results is a strong correlation between age‐1 recruitment success to the Gulf of Maine cod stock and the mean northward wind velocity measured in Massachusetts Bay during May. Based on these findings, we propose a wind index for strong recruitment success of age‐1 cod to the Gulf of Maine stock.