Dermacentor andersoni, demonstration of Anaplasma marginale in hemolymph by animal inoculation and fluorescent antibody technique

gastrointestinal nematodes in calves (exper.) causing severe anemia, effect on preparation of carrier erythrocyte ghosts and erythrocyte survival

A study was conducted to determine aflatoxins in tissues and non-tissues of 2 Holstein cows given oral doses of 0.35 mg of purified aflatoxin B1/kg of body weight/day for 3 consecutive days. Cow 1 was slaughtered 24 hours after the 3rd dose, and cow 2, after day 3, was fed aflatoxin-free rations for 7 additional days before slaughter. Tissue samples of brain, gallbladder and bile, heart, intestine, kidney, liver, lung, mammary gland, skeletal muscle, spleen, supramammary lymph nodes, thymus, and tongue, and nontissue samples of blood, feces, milk, rumen content, and urine were examined. Aflatoxins B1 and M1 were found in all samples of cow 1, except the thymus. Kidney, liver, and mammary gland had the highest concentrations of total aflatoxins (57.9, 13.2, and 25.1 ng/g, respectively), with the aflatoxin M1 concentration 40 times more than the aflatoxin B1 level in kidney. Aflatoxin residues were present (0.02 to 0.11 ng/g) only in kidney, liver, and intestine of the tissues from cow 2 (fed aflatoxin-free feed for 7 additional days). Aflatoxin B1 was not present in nontissue samples, but aflatoxin M1 (0.10 and 1.5 ng/ml) was found in the last milk and urine samples from the same cow. Urine assays are a possible way to monitor the presence of aflatoxin residues in meat tissues.

mature Ostertagia ostertagi and immature Ostertagia spp. in naturally infected dairy calves, activity of levamisole; overwinter survival on pasture of gastrointestinal helminth free-living stages as found in necropsy of previously helminth free calves placed on pasture in April: Kentucky

gastrointestinal nematodes, calves (exper.), efficacy of ivermectin given subcutaneously or given orally as drench or paste

sarcocystosis causing death in calf immediately after birth, rosette and palisade configurations of merozoites in schizonts observed in histologic sections of gray and white matter from cerebrum; encephalitis, to lesser extent meningitis, and necrosis of cerebrum, cerebellum, and brain stem; calf's dam probably was exposed to infective cysts in feed or water contaminated by feces from carnivores

influence of parasitemia level of calves at time of feeding by Dermacentor andersonii upon development of Anaplasma marginale in the ticks

Babesia bovis, cell culture-derived vaccine administered to yearling heifers, immunologic protection against challenge, immune recognition manifested by anamnestic humoral response to challenge

Two of 3 groups of Holstein-Friesian steers (groups II and III; n = 5 each) were fed a ration containing corn naturally contaminated with 800 ng of aflatoxin/g. The other group of steers (group I; n = 5) was fed a ration containing noncontaminated corn. The respective rations were fed for 17.5 weeks, except the ration given to group III; the latter's first diet (contaminated with aflatoxin) was changed to a noncontaminated diet after 15 weeks, continuing for the remaining 2.5 weeks. All steers were killed and tissues and fluids were obtained for aflatoxin analysis. Although aflatoxin B1 and M1 could be detected in blood and urine at several sampling times during the experimental period in groups II and III steers (given the diets containing aflatoxin), there appeared to be no effects on body weight gains and immune phenomena, such as lymphoblastogenesis and antibody production, but there was a waning of the delayed cutaneous hypersensitivity in steers given aflatoxin-contaminated diets. In group III animals (diet was changed to noncontaminated ration at 15 weeks), aflatoxin B1 and M1 disappeared from urine before they were slaughtered. All tissues and fluids, except the rumen contents from these group III steers, were void of detectable aflatoxins B1 and M1 at necropsy. The concentrations of aflatoxin B1 in the rumen content of the latter steers were low. All tissues collected at necropsy from the group II steers fed the aflatoxin diet throughout the 17.5 weeks had detectable aflatoxins B1 or M1 present.

Rhipicephalus simus, 5 types of Anaplasma marginale colonies demonstrated in midgut