Bone mineral density QTL at sexual maturity and end of lay

1. An F₂ cross of a broiler male line and a White Leghorn layer line was used to identify quantitative trait loci (QTL) for bone density at the onset of lay and at the end of the laying period. A total of 686 measures of humeral bone density were available for analysis.

2. There was no evidence for epistasis.

3. Genome-wide significant QTL for bone density at the onset of lay were identified on chromosomes 1 (311?cM) and 8 (2?cM) and on chromosomes 1 (311?cM), 3 (57?cM) and 8 (2?cM) with a covariate for the number of yellow follicles (a proxy for the concentration of circulating oestrogen).

4. Evidence for only 4 chromosome-wide suggestive QTL were detected at the end of lay (72 weeks).

5. Analysis of the combined data confirmed two genome-wide suggestive QTL on chromosome 1 (137 and 266?cM) and on chromosomes 8 (2?cM) and 9 (10?cM) in analyses with or without the covariate.

6. Positive QTL alleles came from the broiler line with the exception of 2 suggestive QTL at the onset of lay on chromosomes 3 and 5 in an analysis with the covariate.

7. In general, QTL acted additively, except that dominant effects were identified for three suggestive QTL at the onset of lay on chromosomes 3 (57 and 187?cM) and 5 (9?cM).

8. The significant QTL in this study were at similar locations to QTL identified in a range of crosses in other publications, suggesting that they are prime candidates for the search for genes and mutations that could be used as selection criteria to improve bone strength and decrease fractures in commercial laying hens.     

Sub-lethal levels of carvacrol reduce Salmonella Typhimurium motility and invasion of porcine epithelial cells

The European ban on the use of antibiotic growth promotors has increased the search for new alternatives to prevent pig intestinal microbial diseases and to stimulate growth. The addition of essential oils or components thereof, such as carvacrol, to pig feed is a promising alternative. In this report we determined the effect of sub-lethal concentrations of carvacrol on Salmonella Typhimurium. At concentrations where growth of Salmonella was not inhibited, carvacrol completely inhibited motility of the bacterium. This loss of motility was not due to the loss of the flagellum or to ATP shortage upon carvacrol treatment. Adhesion of Salmonella to IPEC-J2, porcine intestinal epithelial cells, was not affected by carvacrol but invasion was significantly reduced. In addition, the epithelial gene expression of porcine β-defensin 2, an innate immune response to Salmonella infection, was reduced when Salmonella was exposed to carvacrol. This indicates that invasion but not adhesion of Salmonella triggers the porcine β-defensin 2 expression of porcine epithelial cells.     

Nasolacrimal duct anomaly in calves.

Supernumerary openings of the nasolacrimal drainage apparatus were found in 13 Brown Swiss calves. The cause of the anomaly was not determined but was assumed to be similar to that in man.     

Effect of dry season supplementation of Sanga cattle in Zambia

Supplementation of lactating Sanga cows in central Zambia with low cost crop residues and urea-mineral licks resulted in significant increases in milk offtake (79%), total daily milk (86%), and daily liveweight gain of their calves (86%). At 1988 market prices the value of the additional milk (ZK54.00) and of liveweight of both cow and calf (ZK189.00) over the 13 weeks exceeded the estimated costs of inputs by ZK180.00.     

The gene for familial polyposis coli maps to the long arm of chromosome 5

The inherited genetic defect in adenomatous polyposis has been localized to a small region on the long arm of chromosome 5. Sixteen DNA marker loci were used to construct a linkage map of the chromosome. When five kindreds segregating a gene for adenomatous polyposis coli were characterized with a number of the markers, significant linkage was found between one marker and the disease gene. Linkage analysis determined the location of the defective gene within a primary genetic map of chromosome 5.     

Combined treatment of ocular squamous cell carcinoma in a horse, using radiofrequency hyperthermia and interstitial 198Au implants

Unilateral ocular squamous cell carcinoma in a horse was treated effectively with a combination of repeated radiofrequency hyperthermia and interstitial radiotherapy. These 2 modalities of treatment are synergistic. Interstitial irradiation was achieved, using 198Au implants to deliver a total dose of approximately 5,000 rads/implant over an area of 1 cm2. Radio frequency hyperthermia was repeated 3 times, and radiotherapy was used twice. Treatment resulted in complete regression of the tumor, and ocular complications have not been seen.