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991.
Carol A Morgan Michael McDonald 《Veterinary Clinics of North America: Small Animal Practice》2007,37(1):165-79; abstract x
Veterinarians frequently encounter situations that are morally charged and potentially difficult to manage. Situation involving euthanasia, end-of-life care, economics, and inadequate provision of care create practical and moral dilemmas. Ethical tension may be attributable to differences in beliefs regarding the moral value of animals, client and veterinary responsibilities, and deciding what is best for an animal. Veterinarians can employ communication skills used in medical situations to explore the reasons underpinning ethical dilemmas and to search for solutions with clients, staff, and colleagues. 相似文献
992.
Experiments under controlled environmental conditions were conducted during bloom of prune (Prunus domestica, L.) in 1999 and 2000 to assess the effects of inoculum concentration (IC), wetness duration (WD), temperature, and bloom stages on development of brown rot blossom blight of prunes. Branches from trees of a prune orchard were inoculated with Monilinia fructicola at different bloom stages and incubated at different temperatures with different periods of WD. The proportion of blighted blossoms (PBB) for each inoculated branch was determined. Bloom stage, IC, temperature, and WD significantly affected blossom blight of prunes. PBB at popcorn and full bloom stages was significantly greater than PBB at later bloom stages (P =0.05). The optimal temperatures for blossom blight development were 22 to 26 degrees C, and Gaussian functions were used to describe the relationship between PBB and temperature. PBB linearly increased with increased IC. Linear regressions of PBB on WD were obtained for each combination of bloom stage, IC, and temperature. The parameters of these regressions were used in a computer program to produce the possible maximum PBB with 90% probability (PBB(90)) using stochastic simulations. Early bloom stages with a higher IC at temperatures from 20 to 25 degrees C were associated with more severe blossom blight than late stages with a lower IC at nonoptimal temperatures. Blossom blight did not occur at <10 or >30 degrees C and less than 4-h WD. However, longer than 4-h WD linearly increased incidence of blossom blight. A risk assessment table of blossom blight was produced for different environmental conditions to guide the control of prune brown rot. 相似文献
993.
Stanislawek WL Meers J Wilks C Horner GW Morgan C Alexander DJ 《New Zealand veterinary journal》2001,49(1):18-23
AIMS: To determine the presence of avian paramyxovirus (APMV) types 1, 2, and 3 in caged and wild birds, and APMV-2 and -3 in poultry in New Zealand. METHODS: Blood samples collected from caged (231) and wild birds (522) from various regions of New Zealand in 1997-99 were tested by haemagglutination inhibition (HI) test for antibodies to APMV types 1, 2, and 3. Blood samples collected from 1778 commercial poultry in 1996-99 were tested for APMV-2 and APMV-3 antibodies and the samples that reacted with APMV-3 antigen were tested for antibodies to APMV-1. Isolation of APMV was attempted from cloacal swabs collected from 116 of the caged birds and 175 of the wild birds sampled. RESULTS: Antibodies to APMV types 1, 2, and 3 were detected in 4.8, 1.7, and 2.6%, respectively, of caged bird samples. The majority of these caged birds were 'exotic' or 'fancy' poultry breeds. Amongst wild birds, 4.2% had titres to APMV-2 and over half of these were passerine birds; 1.7% of the samples had titres to APMV-1 and 0.8% to APMV-3 antigen. No virus was isolated from any of the cloacal swabs tested. Of the 1778 poultry serum samples tested, only 5 reacted with APMV-3 antigen and these were later found to be cross-reactions to APMV-1. No reactions were detected with APMV-2 antigen. CONCLUSIONS: APMV-1 is present in caged birds, wild birds, and poultry of New Zealand. There is no conclusive evidence of the presence of APMV-2 and APMV-3 in poultry or APMV-3 in wild birds. The results do not provide conclusive evidence for the presence of APMV-2 in wild birds in New Zealand. 相似文献
994.
995.
MA Hayes BA Quinn ND Keirstead P Katavolos RO Waelchli KJ Betteridge 《Reproduction in domestic animals》2008,43(S2):232-237
A critical period of early gestation in the mare involves the immobilization (fixation) of the encapsulated conceptus at around days 16–17. We compared the major proteins in the normal equine embryonic capsule and endometrial secretions around the period of fixation with those from pregnancies in the process of termination induced by administration of an analogue of prostaglandin F2α (PGF2α ). Uterocalin and β2 -microglobulin (β2 M) associated with the embryonic capsule were proteolytically converted to smaller forms during the fixation period. These conversions were similar in conceptuses from control and treated mares. A 17 kDa cationic protein identified as a secretory phospholipase A2 (sPLA2) type IIA was detected bound to normal capsules but increased substantially in response to PGF2α . Two forms of uteroglobin were distinguished by partial amino acid sequences of ∼6 kDa bands in flush fluids from normal pregnant uteri. After administration of PGF2α one immunoreactive form of uteroglobin was preferentially increased. These studies demonstrate that failure of pregnancy in this model is associated with an increase in secretory phospholipase in the capsule and a change in the forms of uteroglobin in the uterine secretions. 相似文献
996.
Garcia LG Nicholson KL Hoffman TW Lawrence TE Hale DS Griffin DB Savell JW Vanoverbeke DL Morgan JB Belk KE Field TG Scanga JA Tatum JD Smith GC 《Journal of animal science》2008,86(12):3533-3543
The National Beef Quality Audit-2005 assessed the current status of quality and consistency of US fed steers and heifers. Hide colors or breed type were black (56.3%), red (18.6%), Holstein (7.9%), gray (6.0%), yellow (4.9%), brown (3.0%), white (2.3%), and brindle (1.0%). Identification method and frequency were lot visual tags (63.2%), individual visual tags (38.7%), metal-clip tags (11.8%), electronic tags (3.5%), bar-coded tags (0.3%), by other means (2.5%), and without identification (9.7%). Brand frequencies were no (61.3%), 1 (35.1%), and 2 or more (3.6%), and brands were located on the butt (26.5%), side (7.4%), and shoulder (1.2%). There were 22.3% of cattle without horns, and the majority of those with horns (52.2%) were between 2.54 and 12.7 cm in length. Percentages of animals with mud or manure on specific body locations were none (25.8%), legs (61.4%), belly (55.9%), side (22.6%), and top-line (10.0%). Permanent incisor number and occurrence were zero (82.2%), 1 (5.2%), 2 (9.9%), 3 (0.4%), 4 (1.2%), 5 (0.1%), 6 (0.3%), 7 (0.0%), and 8 (0.7%). Most carcasses (64.8%) were not bruised, 25.8% had one bruise, and 9.4% had multiple bruises. Bruise location and incidence were round (10.6%), loin (32.6%), rib (19.5%), chuck (27.0%), and brisket, flank, and plate (10.3%). Condemnation item and incidence were liver (24.7%), lungs (11.5%), tripe (11.6%), heads (6.0%), tongues (9.7%), and carcasses (0.0%). Carcass evaluation revealed these traits and frequencies: steer (63.7%), heifer (36.2%), bullock (0.05%), and cow (0.04%) sex classes; dark-cutters (1.9%); A (97.1%), B (1.7%), and C or older (1.2%) overall maturities; and native (90.9%), dairy-type (8.3%), and Bos indicus (0.8%) estimated breed types. Mean USDA yield grade (YG) traits were USDA YG (2.9), HCW (359.9 kg), adjusted fat thickness (1.3 cm), LM area (86.4 cm(2)), and KPH (2.3%). The USDA YG were YG 1 (16.5%), YG 2 (36.3%), YG 3 (33.1%), YG 4 (11.8%), and YG 5 (2.3%). Mean USDA quality grade traits were USDA quality grade (Select(90)), marbling score (Small(32)), overall maturity (A(64)), lean maturity (A(57)), and skeletal maturity (A(68)). Marbling score distribution was Slightly Abundant or greater (2.7%), Moderate (4.3%), Modest (14.4%), Small (34.5%), Slight (41.2%), and Traces or less (2.9%). This information helps the beef industry measure progress and provides a benchmark for future educational and research activities. 相似文献
997.
Morgan MJ Vite CH Radhakrishnan A Hess RS 《The Canadian veterinary journal. La revue veterinaire canadienne》2008,49(6):583-586
Clinical and electrodiagnostic findings in 3 spontaneously diabetic dogs with clinical peripheral neuropathy (PN) are reported. Clinical signs of a PN may develop in diabetic dogs with adequate glycemic control. In addition, laryngeal paralysis may develop in association with diabetes mellitus in dogs with clinical PN. 相似文献
998.
Morgan ER Tomlinson A Hunter S Nichols T Roberts E Fox MT Taylor MA 《Veterinary parasitology》2008,154(1-2):48-57
The nematode parasite Angiostrongylus vasorum is a source of increasing concern in several parts of the world, where it causes significant disease in dogs. Wild canids, especially foxes, are likely to have a role in the epidemiology of canine infection, and the parasite could also affect fox health and population dynamics. The heart and pulmonary vasculature of 546 foxes culled mostly by gamekeepers in Great Britain in 2005–2006 were examined by dissection and a modified flushing technique. Forty foxes were found to be infected, giving an overall prevalence in the UK fox population of 7.3% (5.3–9.9). Prevalence varied widely between regions, from 0% (0–3) in Scotland and northern England to 23% (16–32) in south-east England. This closely matches the perceived incidence of disease in dogs, which is commonly diagnosed in the south-east but rarely in the north. In the Midlands, where disease has recently appeared in dogs, prevalence in foxes was 4.8% (2–11). Close geographical overlap of parasite distribution in foxes and dogs does not necessarily indicate an important wildlife reservoir of infection, but does suggest that A. vasorum might be spreading northwards. The hearts of infected foxes had thicker right ventricles than those of uninfected foxes, suggesting that the parasite could affect fox health and fitness. Burdens ranged from 1 to 59 adult nematodes. Sex, age and body condition were not significantly associated with infection. Eucoleus aerophilus and Crenosoma vulpis, nematode parasites of the respiratory system, were found in 213 and 11 foxes respectively, with slightly higher prevalence of E. aerophilus in the south and east. No specimens of the heartworm Dirofilaria immitis were found, giving an upper 95% confidence interval for prevalence of 0.84%. 相似文献
999.
Prevalence of the AMHR2 mutation in Miniature Schnauzers and genetic investigation of a Belgian Malinois with persistent Müllerian duct syndrome
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MM Smit KJ Ekenstedt KM Minor CK Lim PAJ Leegwater E Furrow 《Reproduction in domestic animals》2018,53(2):371-376
Persistent Müllerian duct syndrome (PMDS) is a sex‐limited disorder in which males develop portions of the female reproductive tract. Important consequences of PMDS are cryptorchidism and its sequelae of infertility and increased risk of testicular cancer. Anti‐Müllerian hormone (AMH) and its receptor (AMHR2) induce the regression of the Müllerian ducts in male embryos. In Miniature Schnauzer dogs, the genetic basis has been identified as an autosomal recessive nonsense mutation in AMHR2, but the allele frequency of the mutation is unknown. Thus, the primary objective of this study was to estimate the prevalence of the AMHR2 mutation in North American Miniature Schnauzers, in order to ascertain the value of genetic testing in this breed. An additional objective was to determine whether mutations in AMH or AMHR2 were responsible for PMDS in a Belgian Malinois; this would aid development of a genetic test for the Belgian Malinois breed. Genomic DNA from 216 Miniature Schnauzers (including one known PMDS case) was genotyped for the AMHR2 mutation, and DNA from a single PMDS‐affected Belgian Malinois was sequenced for all coding exons of AMH and AMHR2. The Miniature Schnauzer cohort had an AMHR2 mutation allele frequency of 0.16 and a carrier genotypic frequency of 0.27. The genetic basis for PMDS in the Belgian Malinois was not determined, as no coding or splicing mutations were identified in either AMH or AMHR2. These findings support a benefit to AMHR2 mutation testing Miniature Schnauzers used for breeding or with cryptorchidism. 相似文献
1000.