Functional Role of Feline Zona Pellucida Protein 4 Trefoil Domain: A Sperm Receptor or Structural Component of the Domestic Cat Zona Pellucida?

The trefoil domain (TFD) is a protein structure characterized by six cysteines, which form a typical three-loop structure by three disulphide bridges. It is assumed that two of these loops generate a hydrophobic groove, which could be a binding site for carbohydrate residues or proteins. The zona pellucida (ZP) protein, ZP4, contains such a TFD. The carbohydrate-/protein-binding property of TFD allows us to assume a potential sperm receptor function of this domain. Additionally, gastrointestinal trefoil peptides are stable against proteases; therefore, a structural role of TFD within the ZP might also be possible. We were able to show that the synthesized and natural folded feline TFD (fTFD) expresses the typical protease resistance that vanished under reducing conditions and after substitution of cysteine residues within the peptide. Furthermore, an antibody directed against the first loop of fTFD was almost unable to bind to intact in vitro mature cat oocytes. Pre-incubation of oocytes in the reducing agent (DDT), however, improved antibody binding substantially. Therefore, we suggest structural masking of the fTFD domain within the intact ZP. An interaction between fTFD and feline sperm cells was examined using several methods, including immunocytochemistry, immunoelectron microscopy, co-immunoprecipitation and far western blot, but we found no indication for an involvement of TFD in the primary sperm binding to the ZP. To summarize, there is increasing evidence that the TFD of fZP4 has a structural rather than a sperm-binding function.     

Management of quadriceps contracture in a dog using a static flexion apparatus and physiotherapy

A four-month-old golden retriever developed quadriceps contracture following management of a comminuted femoral fracture with an intramedullary pin and cerclage wire. Management involved surgical release of the quadriceps, rigid stabilisation of the fracture, use of a static stifle flexion apparatus and postoperative physiotherapy. The dog returned to full activity with normal stifle function.     

Investigating the phytotoxicity of the graminicide fluazifop-P-butyl against native UK wildflower species

BACKGROUND: The selective graminicide fluazifop‐P‐butyl is used for the control of grass weeds in dicotyledonous crops, and commonly applied in amenity areas to reduce grass productivity and promote wildflower establishment. However, evidence suggests that fluazifop‐P‐butyl might also have phytotoxic effects on some non‐target plants. This study investigates the effects of fluazifop‐P‐butyl on the emergence, phytotoxicity and above‐ground biomass of nine perennial wildflower species and two grass species, following pre‐ and post‐emergent applications at half, full and double label rates in a series of glasshouse experiments. RESULTS: While pre‐ and post‐emergent applications of fluazifop‐P‐butyl caused reductions in seedling emergence and increased phytotoxicity on native wildflower and grass species, these effects were temporary for the majority of wildflower species tested, and generally only occurred at the double application rate. No differences in biomass were observed at any of the rates, suggesting good selectivity and no long‐term effects of fluazifop‐P‐butyl application on the wildflower species from either pre‐emergent or post‐emergent applications. CONCLUSION: These results have direct relevance to the management of amenity areas for biodiversity, as they confirm the suitability of these wildflower species for inclusion in seed mixtures where fluazifop‐P‐butyl is to be applied to control grass productivity. Copyright © 2011 Society of Chemical Industry     

Stress in veterinary science students: a study at the University of Queensland

This paper reports on the results of a survey of selected University of Queensland (UQ) veterinary students aimed at elucidating factors causing stress during the five undergraduate years of the program. Students from each of the five years were asked to form six- or seven-member focus groups. Each focus group was then interviewed and their opinions sought on causes of ongoing stress and the ranking of those causes into predetermined categories. They were also asked to give their opinions on counseling services available within the university and what, if any, services they would like to see in place to help students with stress-related problems. Students in the first, third, and fourth years of the program rated academic issues as the most likely causes of ongoing stress, while students in the second and fifth years of the program ranked lifestyle and financial issues as more likely to cause ongoing stress. In most cases, students coped well with these causes of stress and tended not to use counseling services available to all UQ students. When faced with stressful issues, students looked to their classmates or family members for help and not to university counseling services. Students were also happy to approach staff members in the Veterinary School when faced with a problem. The authors nevertheless conclude that mechanisms set in place at the undergraduate level to help veterinary students cope with stress should particularly benefit those students when they become new graduates and are faced with the stresses of veterinary practice.     

Clinical signs of West Nile virus encephalomyelitis in horses during the outbreak in Israel in 2000

Between August and October 2000, 76 horses were reported by veterinary practitioners as having signs of a neurological disorder, varying from an involvement of the spinal cord alone to the entire central nervous system; 15 of the horses died or were euthanased as a result of their grave prognosis or secondary complications. At the same time, an outbreak of West Nile virus infection affected people and birds, principally domestic geese. West Nile virus was isolated from four of the horses with encephalomyelitis and five other horses seroconverted, indicating that the virus was the probable cause of the outbreak in horses. Three of the cases from which the virus was isolated are described briefly and one case is described in detail. This horse behaved abnormally and had general proprioceptive deficits in all four limbs. Its neurological condition deteriorated after two days and severe inspiratory dyspnoea due to a failure to abduct the arytenoids necessitated a tracheostomy. It died on the fourth day and histological lesions were observed in the brain stem and grey matter of the spinal cord.     

The effects of dietary fat sources,levels, and feeding intervals on pork fatty acid composition

Two experiments investigated the quantitative relationship between dietary fat and fatty acid composition of pork. Experiment 1 was designed to establish the rate of decline for linoleic acid and iodine value of pork fat during the late fattening phase following a dietary reduction. Gilts (n = 288) were fed diets varying in linoleic acid content from 4.11 to 1.56% for 4, 6, or 8 wk prior to slaughter. The maximum rate of decline was 2% 18:2 per week and 2.5 iodine value units per week. Experiment 2 evaluated the effects of dietary fat source and level on carcass fatty acid composition and on pork quality characteristics. Barrows (n = 147) and gilts (n = 147) were allocated to seven dietary treatments for the last 6 wk of the finishing phase. Diets contained 0, 2.5, or 5% dietary fat comprised of 100, 50, or 0% beef tallow. The balance was provided by animal-vegetable blended fat. As the level of tallow increased there was a linear decrease (P < 0.05) in 18:2 content and iodine value of carcass fat. Conversely, 16:1 and 18:1 increased linearly (P < 0.05) as tallow increased. However, 16:1 decreased linearly (P < 0.05) as level of fat increased. As the level of tallow was increased a greater reduction in 18:2 and iodine value was observed in diets with 5% dietary fat compared to diets with 2.5% fat (P < 0.05). These results indicate that reduction of dietary PUFA content had the desired effect of lowering 18:2 content and iodine value of pork fat and that significant alterations could be elicited in as little as 6 to 8 wk of feeding.