Epizootic of anthrax in Falls County, Texas.

An epizootic of anthrax in Eastern Falls County, Texas, killed at least 238 animals during a 6-week period ending July 31, 1974. Infection appeared to be caused by the ingestion of contaminated soil and grass in the drought-stricken central Texas area. The participation of the Texas Department of Agriculture, the Texas National Guard, and other state agencies was of great assistance to the Texas Animal Health Commission in handling the epizootic and panic stricken public. Use of the unencapsulated Sterne strain spore vaccine was credited with preventing many livestock losses in the area. Contaminated city water was detected during the epizootic but human disease did not result.     

Low concentrations of zearalenone in diets of boars for a prolonged period of time

Thirty-two boars were fed diets containing 0, 3, 6 or 9 ppm zearalenone from 32 d of age up to 145 or 312 d of age. Rate of gain, feed intake and gain:feed were not significantly different among treatments. Feeding of diets containing 9 ppm zearalenone did not affect the libido in seven boars. There was a tendency for boars fed 9 ppm dietary zearalenone to produce lower total and gel free volumes of semen, with lower total motile sperm; however, only the percent motility of the sperm was reduced (P less than .05).     

Studies on vitamin E and selenium deficiency in young pigs. III. Effect on kinetics of erythrocyte production and destruction.

The effect of vitamin E and/or selenium deficiency on the kinetics of erythrocyte production and destruction has been investigated in swine. The plasma iron turnover rate, 59Fe incorporation into newly formed red cells as well as the 51Cr apparent red cell half-life, were not found to be significantly affected by either vitamin E deficiency, selenium deficiency or deficiency of both, as compared to replete animals. The results of this study suggest that vitamin E is not a limiting factor for normal erythropoiesis in young growing pigs. Erythropoiesis appeared, however, to be slightly decreased in selenium deficient pigs and will need to be further investigated.     

Babesia major in Britain: cross-immunity trials with Babesia divergens in splenectomised calves.

Splenectomised calves infected with Babesia major were shown to have no resistance to challenge with Babesia divergens; however, initial infection with B divergens provided a good protection against subsequent challenge with B major. It is suggested that this might mean that B divergens would be the dominant and most commonly encountered species in areas where both occur.     

Epidemiological observations on theileriosis following field immunisation using infection and treatment

Thirty-seven high grade cattle were immunised against Corridor disease (Theileria parva lawrencei infection) on a farm with a history of heavy and often lethal theilerial challenge. Nineteen cattle were immunised by treating with two doses of long-acting oxytetracyclines given at 20 mg/kg on days 0 and 4 after sporozoite stabilate inoculation, while the other 18 were treated with naphthoquinone buparvaquone, given as a single dose of 2.5 mg/kg simultaneously with stabilate inoculation. All the cattle underwent subclinical theilerial reactions with all but two developing high antibody titres on the IFAT test against T. parva schizont antigen by day 35 after the immunisation. Both buparvaquone and long-acting oxytetracycline appeared equally effective in the immunisation. To date, 26 months later, only two cases of theileriosis parasitologically characteristic of T. p. parva have been reported in the immunised cattle. Following the two cases, investigations showed that when uninfected Rhipicephalus appendiculatus nymphal ticks were deliberately fed on healthy resident cattle on the farm, the resultant adult ticks transmitted acute and lethal theilerial infections to five out of five susceptible cattle. The resultant infections were parasitologically characteristic of T. p. parva infections. Furthermore, the monoclonal antibody profiles of schizont infected cell lines from these infections appeared to be characteristic of T. p. parva. It was thus concluded that resident cattle on the farm could be a potential source of T.p. parva infection which had broken through the immunity of T.p. lawrencei immunised cattle and could constitute a reservoir of theilerial infection for ticks and hence to susceptible stock on the farm.     

Site of protein digestion in steers fed sorghum grain diets. I. Effect of level of feed intake

Two digestion trials were conducted with seven crossbred, abomasally cannulated yearling steers (400 kg) to study the effect of level of feed intake on the site and extent of feed and microbial protein digestion. Steers, in a crossover design experiment, were fed an 81.5% steam-processed flaked (SPF) sorghum grain diet at either 95% (four steers) or 75% (three steers) of their ad libitum intakes. At the end of the first trial, steers were switched to the opposite treatment. Dysprosium (31 to 32 micrograms/g) was used as an external marker. Feed, abomasal contents and fecal grab samples were taken at 12-h intervals advancing by 2 h each day over a 6-d total fecal collection period. Organic matter (OM) intakes were 6,102 and 4,570 g for the two treatments. Higher level of intake increased (P less than .05) quantities of OM, crude protein and trichloroacetic acid precipitable protein entering the small intestine, digested post-ruminally and digested in the total tract. The higher level of intake decreased (P less than .05) the percentage of bacterial protein (BP) present in the abomasum and percent post-ruminal BP digestion; however, the amounts of BP and non-BP entering the small intestine and digested post-ruminally were greater (P less than .05) in steers fed 95% ad libitum. Most of the feed protein was degraded in the rumen with both treatments. Predicted true feed protein digestibilities were 91.1 and 91.7% for 95 and 75% of ad libitum intakes.(ABSTRACT TRUNCATED AT 250 WORDS)