A total of two hundreds of slaughtered animals; 50 each of cattle buffaloes, sheep and buffalo calves were collected from slaughterhouse Giza. Each animal was represented by muscular part, prenephric fat, liver, and kidneys. The Four Plate Technique (FPT) is intended to detect antimicrobial residues in collected samples. The liver samples showed high detection incidences (30, 16, 16 and 8%) in cattle, buffaloe, sheep and buffaloe calves respectively as compared to kidney samples (16, 12, 10 and 6% respectively). The lowest incidence was detected in fat samples (0%) followed by muscle samples (4%). High incidence was detected in medium I followed by medium II and III, finally medium IV as well as medium V which failed to be showed any incidence of detection. The tetracycline residues in tissues of slaughtered animals depend on husbandry as well as on withdrawal time after use. The liver (67 + 15, 50 + 14, 54 + 10 and 3 +0.8) and kidney (63 + 16, 46 + 12, 56 + 12 and 8 + 2) samples in cattle, buffaloe, sheep and buffaloe calves respectively showed high residual levels as compared with muscles and fat. The detection of sulfonamide residues in tissues of slaughtered animals may be attributed to misuse of these compounds for long term in animal feed as well as result in accumulation in animal tissues.

Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE) of Rocky Mountain elk in North America. Recent studies suggest that tissue and blood mineral levels may be valuable in assessing TSE infection in sheep and cattle. The objectives of this study were to examine baseline levels of copper, manganese, magnesium, zinc, selenium, and molybdenum in the brains of Rocky Mountain elk with differing prion genotypes and to assess the association of mineral levels with CWD infection. Elk with leucine at prion position 132 had significantly lower magnesium levels than elk with 2 copies of methionine. Chronic wasting disease-positive elk had significantly lower magnesium than control elk. The incorporation of manganese levels in addition to magnesium significantly refined explanatory ability, even though manganese alone was not significantly associated with CWD. This study demonstrated that mineral analysis may provide an additional disease correlate for assessing CWD risk, particularly in conjunction with genotype.

This report describes the genetics of the prion protein gene (PRNP) at codons 136, 154, and 171 for sheep diagnosed with naturally acquired classical scrapie in Canada between 1998 and 2008. Genotyping analysis was performed on 249 sheep with confirmed classical scrapie infection representing 98 flocks from 6 provinces. A further case-control analysis of 3 of these flocks compared the genotypes between infected sheep (n = 72) and those of their healthy flockmates (n = 1990). The incidence of classical scrapie in the Canadian sheep population was highly associated with the ARQ haplotype (91.8%) and the ARQ/ARQ genotype (91.6%). In addition, the ARQ haplotype was found at significantly higher frequency in scrapie-infected sheep when compared with their healthy flockmates. Comparison with other published data suggests that the scrapie risk of PRNP genotypes differs between Canada and countries where the VRQ allele is associated with the highest susceptibility to infection.

Objective--To determine the contribution of 7,8-methylenedioxylycoctonine (MDL)–type alkaloids to the toxic effects of tall larkspur (Delphinium spp) consumption in cattle. Animals--Sixteen 2-year-old Angus steers. Procedures--Plant material from 3 populations of tall larkspur that contained different concentration ratios of MDL-type-to-N-(methylsuccinimido) anthranoyllycoctonine (MSAL)–type alkaloids was collected, dried, and finely ground. For each plant population, a dose of ground plant material that would elicit similar clinical signs of toxicosis in cattle after oral administration was determined on the basis of the plants' MSAL-type alkaloid concentration. Cattle were treated via oral gavage with single doses of ground plant material from each of the 3 populations of tall larkspur; each animal underwent 1 to 3 single-dose treatments (> = 21-day interval between treatments). Heart rate was recorded immediately before (baseline) and 24 hours after each larkspur treatment. Results--Tall larkspur populations with a lower MDL-type-to-MSAL-type alkaloid concentration ratio required a greater amount of MSAL-type alkaloids to cause the expected clinical signs of toxicosis (including increased heart rate) in cattle. Conclusions and Clinical Relevance--Results indicated that the typically less toxic MDL-type alkaloids contributed in a significant manner to the toxic effects of tall larkspur in steers. Consequently, both the concentration of MSAL-type alkaloids and the total concentration of MSAL- and MDL-type alkaloids should be determined when assessing the relative toxicity of tall larkspur populations. These results provide valuable information to determine the risk of toxicosis in cattle grazing on tall larkspur–infested rangelands.

Molecular genetic data provide powerful tools for genealogy reconstruction to reveal mechanisms underlying disease ecology. White-tailed deer (Odocoileus virginianus) congregate in matriarchal groups; kin-related close social spacing may be a factor in the spread of infectious diseases. Spread of chronic wasting disease (CWD), a prion disorder of deer and their cervid relatives, is presumed to be associated with direct contact between individuals and by exposure to shared food and water sources contaminated with prions shed by infected deer. Key aspects of disease ecology are yet unknown. DNA tools for pedigree reconstruction were developed to fill knowledge gaps in disease dynamics in prion-infected wild animals. Kinship indices using data from microsatellite loci and sequence haplotypes of mitochondrial DNA were employed to assemble genealogies. Molecular genealogy tools will be useful for landscape-level population genetic research and monitoring, in addition to epidemiologic studies examining transmission of CWD in captive and free-ranging cervids.

In the conditions of the Republic of Belarus there was studied the influence of a number of pigs in a group on swine productivity and blood indexes of pigs. In course of the study there were analyzed blood indexes of piglets before and at the end of the experiment. Research results showed that it was efficient to organize husbandry in small groups (10 heads per carriage). The adaptative period of animals in the conditions of husbandry in large groups (20 heads) was longer (the adaptation took place by the seventh day). In these conditions the average daily live weight gain of piglets was lower than in the conditions of small group husbandry on 5,1%. Research results showed that animal husbandry in the conditions of different number of heads per group did not render negative influence on morphological and biochemical blood composition.