Prevalence of Tritrichomonas foetus in several subpopulations of Alabama beef bulls.

The objective of this study was to estimate the prevalence of Tritrichomonas foetus infections in Alabama (USA) beef bulls through prospective and retrospective surveys. The prospective survey included 240 Alabama beef bulls that were sampled between January 2005 and March 2006. Preputial smegma was collected from the 240 bulls with a dry pipette and cultured in an InPouch TF T. foetus culture pouch (BioMed Diagnostics; White City, OR, USA). The samples were evaluated microscopically once a day for 6 days for growth resembling T. foetus. To avoid false-positives due to fecal trichomonads, all suspect cultures were sent to both the Alabama Department of Agriculture Veterinary Diagnostic Laboratory in Auburn, AL, USA and the Auburn University College of Veterinary Medicine Parasitology Laboratory (Auburn, AL, USA) for polymerase chain reaction (PCR) confirmatory assays. Of the 240 bulls cultured in the prospective survey, 3 (1.25%) cultures were considered suspect on microscopic evaluation. However, PCR-based assays were negative for T. foetus, suggesting that the samples most likely contained fecal trichomonads. The retrospective analysis included 374 T. foetus cultures performed at the Alabama Department of Agriculture Veterinary Diagnostic Laboratory between October 2002 and March 2005. Of the 374 bulls included in the retrospective analysis, only 1 (0.27%) was confirmed positive by a PCR-based assay.

Differentiation of gastrointestinal diseases of calves.

With a complete history, careful physical examination, and targeted diagnostics, the practitioner can differentiate the causes of gastrointestinal diseases in calves. The authors hope that this article helps the practitioner in this regard. Armed with a diagnosis, he or she can then proceed with proper treatment and prevention, which is the ultimate goal.

Idiopathic photoreceptor dysfunction causes unexplained visual acuity loss in later adulthood.

Progressive visual loss, caused by initially unrecognized retinal photoreceptor dysfunction predominantly affecting cones, developed in six patients in late adulthood. Because of minimal ophthalmoscopic retinal abnormalities, the patients initially had been suspected of having optic neuropathy or psychogenic visual loss. The correct diagnosis was ultimately established by finding electroretinographic abnormalities and color discrimination losses out of proportion to visual acuity loss. In no case was a causative agent or a family history of photoreceptor disease identified. In many other respects, however, features of the patients' illness resemble those described previously under the headings of cone dysfunction syndrome, cone dystrophy, cone degeneration, and cone-rod dystrophy.

Plasma sex hormone and lipid patterns in normal and restricted-ovulator chicken hens.

The relationships of circulating estradiol, estrone, and progesterone levels to plasma lipid levels and ovulatory frequency were studies in sexually mature hens. New Hampshire X Columbian (NH X C) cross-bred hens, which have a relatively low frequency of ovulation, were compared with pure-bred White Leghorn (WLH) hens with a high frequency of ovulation. A mutant strain of WLH hen, exhibiting the phenotypic characteristic of restricted ovulation (RO) was also tested. It was fund that NH X C hens had a basal circulating estrogen: progesterone ratio 2.7 X greater than WLH hens. Furthermore, WLH-RO hens exhibited 3 X HIGHER BASAL PLASMA ESTROGEN AND 4 X lower progesterone than normal WLH hens, resulting in an estrogen:progesterone ratio which was l2.6X higher. In additional, WLH-RO hens did not exhibit any diurnal variation in circulating progesterone levels, and had smaller primary sex organs and also intermittent hyperlipidemia. It is concluded that the basal circulating estrogen:progesterone ratio in sexually mature hens is a good indicator of ovulatory frequency, and that the magnitude of the ratio is determined primarily by the progesterone component.

Effects of d-norgestrel-releasing intracervical devices in the nonhuman primate, Erythrocebus patas.

Primates (Erythrocebus patas) were implanted with intracervical devices which slowly released d-norgestrel at either of two rates: 38 +/- 12 microgram/day (high dose, 4 animals) or 14 +/- 10 microgram/day (low dose, 3 animals). An additional 8 animals received placebo devices or were untreated controls. All animals were studied for 3 months of exposure, at which time they were necropsied and evaluated. The uterus in all of the high dose primates had endometrial stromal and epithelial hyperplasia and, in two primates, suppurative endometritis. Similar, but less severe, uterine changes were present in animals of the low dose group. Systemic effects included evidence of diminished menstrual cycling and an absence of corpora lutea at both dose levels. Our results indicate that local application of these levels of d-norgestrel for contraception produces effects similar to those from systemically administered d-norgestrel.