Analysis of the reactivity of anti-bovine CD8 monoclonal antibodies with cloned T cell lines and mouse L-cells transfected with bovine CD8

Mouse L-cells transfected with bovine CD8 and two Theileria parva-infected cloned T cell lines expressing bovine CD8 were used to screen the panel of ten monoclonal antibodies (mAbs) submitted to the workshop. Eight of the ten mAbs reacted with the transfectant and both the cloned T cell lines. However, two mAbs CC58 and BAT82A did not recognise the transfectant and only reacted with one of the T cell lines. Further biochemical studies indicated that the eight mAbs react with both homo- and heterodimeric forms of bovine CD8 whilst the two mAbs CC58 and BAT82A react with only heterodimeric forms. These data suggest that bovine DC8 is encoded by two genes as is the case in mouse and man.     

Microorganisms associated with pneumonia in slaughter weight swine.

The lungs of 334 pigs were obtained from two slaughter plants in Minnesota and examined in detail. Macroscopic and microscopic evaluation, direct fluorescence for Mycoplasma hyopneumoniae and bacterial culture were done on all of them and a subsample of 50 were selected for virus culture. Mycoplasma hyopneumoniae, Pasteurella multocida and Haemophilus spp. were detected in 24.0%, 34.1% and 27.0% of the lungs, commonly in conjunction with each other. One isolate of Haemophilus pleuropneumoniae serotype 2 was detected and this represents the first report of its presence in the United States. No virus was detected in any of the lungs. Lungs with both M. hyopneumoniae and Pasteurella multocida had the greatest amount of macroscopic pneumonia (9.8% of the lung). Lungs with M. hyopneumoniae or P. multocida alone had 4.9% and 5.2% of the lung involved with pneumonia respectively. Lungs with Haemophilus sp. Taxon "minor group" had 3.8% of the lung involved which was not significantly different from lungs with none of these organisms being detected (1.6%). There was a positive correlation between the extent of M. hyopneumoniae infection, as scored by FAT and the amount of macroscopic pneumonia present (r = 0.46; P less than 0.001). Likewise, there was a positive correlation between the estimated concentration of P. multocida present, as scored by the relative number of colonies on blood agar and the amount of macroscopic pneumonia present (r = 0.60; P less than 0.001). Microscopically, the amount of lymphoreticular proliferation, polymorphonuclear cells and alveolar macrophages were evaluated.(ABSTRACT TRUNCATED AT 250 WORDS)     

Mixed models applied to the study of variation of grower-finisher mortality and culling rates of a large swine production system

Large scale production systems for swine are frequently organized in a hierarchical structure. Consequently, important production parameters, such as mortality and culling, can be analyzed at different levels. The major aims of this study were to assess variance components (VC) of mortality and culling rates attributed to sites and to barns within a site, and subsequently to investigate the impact of average entry weight, days on feed (length of the production turn), and season on the magnitude of the VC. Then, data from a large farm with 3 sites were collected during 5 y. In total, 1720040 pigs distributed in 1502 all-in/all-out grower-finisher groups were included. Linear mixed models were fitted for mortality and culling rates. The barn was modeled as the residual component (barn-to-barn variations) with production turn and site nested within production turn as random intercept variance components. Barn-to-barn pig group variation was the largest VC for mortality (63.08%), when no predictors were included in the models. Predictors, such as pigs placed on quarters 2 and 3, low average entry weight, and shorter production turn length, were associated together with higher mortality. The explained proportion of variance due to these predictors was about 12.05% and the VC for barn, site, and production turn were 67.6%, 17.6%, and 14.8%, respectively. Barn-to-barn variation was also the largest VC for culling rate (46.2%), but the same predictor mentioned above explained only about 1.4% of the variation. The VC for barn, site, and production turn were 46.8%, 21.3%, and 31.8%, respectively. Since the variability among barns far exceeded the variability among sites, the barn should be used as experimental unit in studies with grower-finisher mortality, culling rate, or both, as outcome variables.     

Effect of Fermentation and Oil Incorporation on the Retention of E Vitamers During Breadmaking

All forms of baking and processing cause a loss of nutrients, including vitamin E, but little is known about these occurrences or if they could be avoided. The objective of this research was to study the incorporation of palm oil and the stability of vitamin E in palm oil during breadmaking. Wheat meal and rye breads were baked with and without the addition of 0, 2, 5, or 8% palm oil. The eight E group vitamers (tocopherols and tocotrienols) were extracted by using accelerated solvent extraction, freeze dried, and then analyzed with normal‐phase HPLC. Compared with the controls, the inclusion of palm oil was found to increase the quantity of all forms of vitamin E in the final baked products. It is concluded that palm oil is effective in increasing the vitamin E content of whole grain bread.     

Key Factors Affecting Reproductive Success of Thoroughbred Mares and Stallions on a Commercial Stud Farm

To evaluate factors contributing to fertility of thoroughbred mares, data from 3743 oestrous periods of 2385 mares were collected on a large thoroughbred farm in Ireland. Fourteen stallions (mean age 8.3 years; range 4–15 years) had bred 2385 mares (mean age 9.4 years; range 3–24 years). Maiden mares accounted for 12%, mares with a foal at foot for 64%, and barren, slipped or rested mares for 24% of the total. The mean pregnancy rate per cycle was 67.8% (68.6% in year 1 and 66.9% in year 2). Backward stepwise multivariable logistic regression analysis was utilized to develop two models to evaluate mare factors, including mare age, reproductive status, month of foaling, dystocia, month of cover, foal heat, cycle number, treatments, walk‐in status and stallion factors including stallion identity, stallion age, shuttle status, time elapsed between covers and high stallion usage on the per cycle pregnancy rate and pregnancy loss. Old age (p < 0.001) and cover within 20 days post‐partum (p < 0.003) were associated with lowered pregnancy rates. High mare age (p < 0.05) and barren, slipped or rested reproductive status (p = 0.05) increased the likelihood of pregnancy loss. Uterine inflammation or infection, if appropriately treated, did not affect fertility. Only high usage of stallions (used more than 21 times in previous week) was associated with lowered (p = 0.009) pregnancy rates. However, shuttle stallions were more likely to have increased (p = 0.035) pregnancy survival, perhaps reflecting a bias in stallion selection. In conclusion, mare age exerted the greatest influence on fertility; nonetheless, thoroughbreds can be effectively managed to achieve high reproductive performance in a commercial setting.     

Effect of orally administered Lactobacillus casei on porcine reproductive and respiratory syndrome (PRRS) virus vaccination in pigs

The purpose of this study was to determine whether intranasal/oral administration of probiotics can assist vaccination efficacy against an important swine pathogen, porcine reproductive and respiratory syndrome (PRRS) virus (PRRSV). A controlled challenge trial was performed employing: (a) pigs vaccinated against PRRS and treated with a Lactobacillus casei, (b) pigs vaccinated against PRRS only, (c) pigs treated with L. casei only, and (d) pigs neither vaccinated against PRRS nor treated with L. casei. All pigs were challenged intranasally with a wild PRRSV strain. There was no difference in clinical signs or rectal temperature among the four groups. However, pigs that received L. casei gained significantly more weight than pigs that did not. Vaccinated pigs did not gain more weight than nonvaccinated pigs. Vaccinated groups had significantly fewer viraemic pigs on days post-challenge 4, 11 and 17 than nonvaccinated groups of pigs. There was no effect of probiotic on prevalence or duration of viraemia. Among viraemic pigs, there was no significant difference in mean log base(10) titer of PRRS virus among groups. These results suggest that orally administered L. casei does not affect immune response in such a way as to affect PRRS viraemia or nasal shedding. However, it still appears to provide significant benefit when administered during vaccination as indicated by the higher bodyweight gain following PRRS virus infection.     

Effect of Pheromone Blend Components,Sex Ratio,and Population Size on the Mating of Cadra cautella (Lepidoptera: Pyralidae)

The almond moth Cadra cautella (Walker), a key pest of storage facilities, is difficult to manage using synthetic chemicals. Pheromone-based management methods remain a high priority due to advantages over conventional management practices, which typically use insecticides. Cadra cautella females release a blend of pheromone including (Z, E)-9,12-tetradecadienyl acetate (ZETA) and (Z)-9-tetradecadien-1-yl acetate (ZTA). The effect of these components on mating of C. cautella and how response varies with the population density and sex ratio remain unknown. In this study, the mating status of C. cautella was studied inside mating cages under different ratios of ZETA and ZTA diluted in hexane and at different population sizes either with equal or unequal sex ratio. The lowest percentage of mated females (highest mating disruption [MD] effects), corresponding to roughly 12.5%, was produced by a 5:1 and 3.3:1 ratio of ZETA:ZTA. Populations with equal sex ratio showed the lowest percentage of mated females, at 20% and 12.5% under lower and higher density, respectively. The next lowest percentage of mated females was produced when the sex ratio was set to 1: 2 and 2:1 male:female, with just 25% and 22.5% of moths mated, respectively. This study shows that mating status of C. cautella is influenced by ZETA:ZTA ratio, sex ratio, and population size. This current knowledge would have useful implications for mating disruption programs.     

Current status of asymmetric synthesis

In the last 30 years the subject of asymmetric synthesis has grown from a little studied academic niche in organic chemistry to an intensely investigated field of commercial importance and heightened general interest. Impressive advances have been made in several areas, notably catalytic asymmetric homogeneous hydrogenation, catalytic asymmetric epoxidation of allyl alcohols and stereochemical control of carbon-carbon bond-forming reactions. Asymmetric synthesis must now be deliberately considered along with other available methods as a practical strategy for the synthesis of any chiral compound.     

A multi-method approach to delineate and validate migratory corridors

Context

Managers are faced with numerous methods for delineating wildlife movement corridors, and often must make decisions with limited data. Delineated corridors should be robust to different data and models.

Objectives

We present a multi-method approach for delineating and validating wildlife corridors using multiple data sources, which can be used conserve landscape connectivity. We used this approach to delineate and validate migration corridors for wildebeest (Connochaetes taurinus) in the Tarangire Ecosystem of northern Tanzania.

Methods

We used two types of locational data (distance sampling detections and GPS collar locations), and three modeling methods (negative binomial regression, logistic regression, and Maxent), to generate resource selection functions (RSFs) and define resistance surfaces. We compared two corridor detection algorithms (cost-distance and circuit theory), to delineate corridors. We validated corridors by comparing random and wildebeest locations that fell within corridors, and cross-validated by data type.

Results

Both data types produced similar RSFs. Wildebeest consistently selected migration habitat in flatter terrain farther from human settlements. Validation indicated three of the combinations of data type, modeling, and corridor detection algorithms (detection data with Maxent modeling, GPS collar data with logistic regression modeling, and GPS collar data with Maxent modeling, all using cost-distance) far outperformed the other seven. We merged the predictive corridors from these three data-method combinations to reveal habitat with highest probability of use.

Conclusions

The use of multiple methods ensures that planning is able to prioritize conservation of migration corridors based on all available information.