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41.
1. The objective of the present study was to examine the behaviour of laying hens in single-tiered aviaries with and without outdoor areas with particular reference to the proportion of each behaviour and the ways it changed. 2. In all, 144 interbred cross layers (WL/RIR cross-breed) were used. At the age of 16 weeks, the hens were divided at random into two groups and moved to single-tiered aviary (SA) and free-range systems (FR, SA with in addition an outdoor range area covered with clover) with 18 hens per pen. Behavioural observations were conducted before, during and after access to the range. 3. All behaviours using the beak (eating, grazing, drinking, preening, aggressive pecking, feather pecking, litter pecking, object pecking and mate pecking) were recorded as pecking behaviour. 4. While most of the FR hens spent their time outside foraging, the proportion of hens eating, preening, litter pecking, object pecking, aggressive pecking and feather pecking was higher in SA than in FR hens. 5. The proportion of hens performing pecking behaviour of all types was very similar in SA (61.7 +/- 2.0%) and in FR (64.0 +/- 0.8%). The proportion of hens performing overall pecking behaviour increased as pre-laying sitting decreased. 6. The proportion of hens feather pecking decreased in FR during access to range and a similar tendency was found for aggressive pecking. 7. In conclusion, the total proportion of hens pecking was almost the same regardless of whether an outdoor area was provided or not, but the incidence of different types of pecking behaviour differed between SA and FR. The risk of feather pecking in FR may be lower when an outdoor grazing area is provided, although further testing on a larger scale would be essential.  相似文献   
42.
To examine the effects of exogenous porcine (p) ST on measures of stress and immune function in weaned pigs with or without transport, pigs (20 +/- 1 d of age) received daily injections of pST (0.5 mg/kg; n = 16) or saline (n = 16) for 5 d. On d 5, a blood sample was collected immediately before injection. At 4 h postinjection, pigs were weighed, sampled for blood, injected with di-nitrophenyl-conjugated keyhole limpet hemocyanin, and weaned. One half of the pigs in each group were transported for 3 h before placement in the nursery. Pigs were weighed, and blood was collected on 1, 7, and 14 d postweaning. Statistical significance was set at P < 0.05. Serum IGF-I concentrations were increased by pST and decreased by weaning, but not affected by transport. The free cortisol index was elevated in all pigs 1 d postweaning, although less in transported versus nontransported pigs. By 7 d postweaning, the free cortisol index returned to prewean values. Serum concentrations of immunoglobulin (Ig) G increased in all pigs by 14 d postweaning, but were not affected by pST or transport. Serum IgM concentrations were elevated at 7 and 14 d postweaning. Before weaning and again 1 d postweaning, pigs treated with pST had greater concentrations of IgM than did control animals. Circulating neutrophils increased in pST-treated pigs 4 h after the final pST injection. Improved immune function in weaned pigs by pST may lead to greater health and growth in a commercial setting.  相似文献   
43.
Prevalence of dental disorders in 483 horses and ponies Five equine veterinarians working at three equine referral hospitals examined the oral cavity of 483 horses and ponies prior to surgery, to gain information about the prevalence of common dental disorders in the horse. A thorough examination, using hands/fingers, a full-mouth speculum, a dental mirror and a good light source, is essential to detect such disorders. Many horses examined needed dental attention even though there were no problems with mastication or riding. The most detected abnormalities were sharp enamel points on the buccal side of the upper arcade and the lingual side of the lower arcade, and hooks at 106/206 and 311/411. Regular dental care would improve the condition and welfare of horses.  相似文献   
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A pleomorphic adenoma of the lacrimal gland in a dog   总被引:1,自引:0,他引:1  
A 13-year-old female mongrel dog had a pleomorphic adenoma of the lacrimal gland in the right upper orbit. The tumor measured 3.8 x 3.0 x 3.3 cm, appeared white, round, and firm, and pressed the right globe and surrounding tissues. Histopathologically, the tumor had a thin connective tissue capsule and was composed of tubules with two cell types, some resembling luminal epithelial cells making up the tubular structures and the other of myoepithelial cells. Epithelial tubules were disposed in an adenomatous fashion and separated from each other by proliferating pleomorphic myoepithelial cells. Immunohistochemically, large numbers of the luminal epithelial cells revealed an immunopositive reaction against keratin/cytokeratin (AE1/AE3), and some epithelial cells reacted against cytokeratin 14. Spindle-shaped myoepithelial cells revealed an immunopositive reaction against cytokeratin 14, alpha-smooth muscle actin, and vimentin. A small number of myoepithelial cells reacted against desmin. S-100 protein immunopositivity was frequently found in luminal epithelial cells and rarely in the pleomorphic myoepithelial cells. Glial fibrillary acidic protein positivity was commonly found in myoepithelial cells, myxoid matrices, and intracystic materials, but not in luminal epithelial cells.  相似文献   
46.
47.
A consensus nested PCR was used to screen diagnostic samples from approximately 70 reptiles for the presence of adenoviruses (AdV) in the years 2006-2007. Classical virus isolation methods were also used with all samples. After adenoviruses were detected in a group of helodermatid lizards in a Danish zoo, a follow-up study was also carried out on lizards from this group (10 Mexican beaded lizards and 24 Gila monsters) over the period of a year. Adenoviruses were detected in a total of 26 lizards and snakes by PCR. The PCR amplicons from all positive animals were sequenced and the resulting polymerase gene sequences were used for phylogenetic analysis. Altogether six Agamid AdVs were amplified, with a minimal sequence variation between one another and between these and GenBank Agamid AdVs. The sequence obtained from one of the Gila monsters is identical with the GenBank Helodermatid AdV, while the sequences from the Mexican beaded lizards differ from this. In a snake collection we have detected a new AdV from an Asp viper. All of the above mentioned adenoviruses cluster in the Atadenovirus genus. However, the sequence from a new Varanid AdV detected in this study clusters outside this genus. On cell culture, viruses were isolated from three of the AdV positive helodermatid lizards (one Mexican beaded lizard and two Gila monsters) and identified as AdVs based on electron microscopy and PCR and sequencing using cell culture supernatant. This is the first report of the successful isolation of a lizard AdV.  相似文献   
48.
Since the isotopes can not be utilized for veterinary patients in Japan, the authors developed a simple calculation formula of shunt fraction of portosystemic shunt based on the hepatic circulation model. The shunt fraction can be calculated utilizing only 2 portal pressure measurements of pre-shunt ligation and temporary or permanent shunt ligation. The calculated shunt fraction can obtained pre-ligation and post-ligation either temporally or permanent complete shunt ligation: complete ligation group of PSS (n=59) had 48.2 +/- 16.9% of shunt fractions, whereas the partial ligation group (n=48) had 71.6 +/- 10.7% of shunt fractions.  相似文献   
49.
50.
ABSTRACT: Foot-and-mouth disease virus (FMVD), one of the most contagious viruses of cloven-hoofed animals, may cause a prolonged, asymptomatic but persistent infection in ruminants, named the "carrier state". However, it remains an open question whether this carrier state occurs in pigs. Here we present quantitative analyses of the duration of FMDV RNA and infectivity in lymphoid and epithelial tissues in experimentally infected pigs with FMDV C-S8c1. The data indicated that although FMDV RNA remained in blood until day 14 post-infection (pi), viremia was cleared by day 7 pi. However, all tissues tested were positive for FMDV until day 14-17 pi. Interestingly, the specific infectivity of FMDV in these tissues was in some cases even higher than the FMDV C-S8c1. We therefore propose that a "pseudopersistent state" may occur in pigs in which virus replicates in lymphoid tissues for a prolonged period of time, thereby representing a potential source of virus.  相似文献   
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