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The stratum corneum (SC), the outermost layer of the epidermis, serves a crucial role in maintaining body hydration and protection from environmental insults. When the stratum corneum is injured or when the genetic blueprints are flawed, the body is at risk of dehydration, secondary infections and allergen sensitization. Advancements in veterinary dermatology have revealed a wide gamut of disease from relatively benign to lethal that specifically arise from flawed structural proteins, enzymes or lipids needed to create the corneocytes and lipid bilayers of the SC. Some conditions closely mimic their human counterparts while others are unique to the dog. This review will focus on forms of ichthyosis in the dog.  相似文献   
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Digital dermatitis (DD) is a major infectious foot disease of cattle worldwide. Some DD stages are associated with lameness, and the disease has significant economic and animal welfare consequences. The pathogenesis of the disease is not yet fully understood, but Treponema spp. have been associated consistently with clinical cases. Isolation of these fastidious bacteria is difficult and cumbersome. We describe an improved method enabling the culturing of the 3 Treponema spp. (T. pedis, T. phagedenis, and T. medium) from bovine foot specimens derived from DD lesions, using a combination of membrane filtering and subsequent growth on selective agar media. The entire procedure from sampling to verification of individual Treponema spp. takes up to 24 d. In addition, we established a MALDI-TOF MS–based identification method to be applied for confirmation of the different Treponema spp. This scheme provides an unambiguous, simple, and straightforward identification procedure for DD-associated Treponema spp.  相似文献   
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ObjectiveTo quantify induction time, reliability, physiological effects, recovery quality and dart volume of a novel formulation of alfaxalone (40 mg mL?1) used in combination with medetomidine and azaperone for the capture and handling of wild bighorn sheep.Study designProspective clinical study.AnimalsA total of 23 wild bighorn sheep (Ovis canadensis) in Sheep River Provincial Park, AB, Canada.MethodsFree-ranging bighorn sheep were immobilized using medetomidine, azaperone and alfaxalone delivered with a remote delivery system. Arterial blood was collected for measurement of blood gases, physiologic variables (temperature, heart and respiratory rates) were recorded and induction and recovery length and quality were scored.ResultsData from 20 animals were included. Administered dose rates were alfaxalone (0.99 ± 0.20 mg kg?1; 40 mg mL?1), azaperone (0.2 ± 0.04 mg kg?1; 10 mg mL?1) and medetomidine (0.16 ± 0.03 mg kg?1; 30 mg mL?1). The mean drug volume injected was 1.51 mL. The median (range) induction time was 7.7 (5.8–9.7) minutes, and recovery was qualitatively smooth.Conclusions and clinical relevanceAn increased concentration formulation of alfaxalone was administered in combination with medetomidine and azaperone, and resulted in appropriate anesthesia for the capture and handling of bighorn sheep. The dart volume was small, with potential for reducing capture-related morbidity.  相似文献   
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The aim of our study was to examine effects of the length of semen equilibration as well as two freezing techniques on ram sperm post-thaw quality. The ejaculates of Wallachian sheep rams (n = 12) were collected by an electro-ejaculation, equilibrated in a Triladyl® (0, 2, 4, 6, and 8 h) containing glycerol and egg yolk and frozen by programmable freezing (PF) or manual freezing (MF). After thawing, sperm samples were subjected to the motility (computer-assisted sperm analysis [CASA]), viability (SYBR-14/PI), and fertilizing ability (FA) (in vitro penetration/fertilization test on bovine oocytes) assays. It was found that the equilibration of 6 h (E-6) ensured higher post-thaw sperm motility and progressive movement compared with other lengths tested, irrespective of a freezing technique. The E-6 sperm viability did not differ between PF and MF but was lower (P < 0.05) than control. Sperm FA (E-6) was similar in PF (60.44%) and MF (62%) but slightly lower than in fresh (72.8%). Our data demonstrate that the use of MF was comparable with PF, which can be applied in the field conditions without need in a piece of cost-expensive equipment, which can greatly benefit the gene bank of animal genetic resources.  相似文献   
46.
In this study the starch digestion rates in broiler chickens from 18 samples of 5 commonly used feed grains (sorghum, wheat, maize, barley, triticale) were determined. The methodology to determine starch digestion rates in poultry is detailed herein. Starch digestion rates were not significantly different (P = 0.128) across the 18 feed grains, which reflects the wide variations that were observed within a given feedstuff. Nevertheless, starch digestion rates in broiler chickens offered wheat-based diets were significantly more rapid by 56.0% (0.117 versus 0.075 min−1; P = 0.012) than their sorghum-based counterparts on the basis of a pair-wise comparison. In descending order, the following starch digestion rates were observed: wheat (0.117 min−1), barley (0.104 min−1), triticale (0.093 min−1), maize (0.086 min−1), sorghum (0.075 min−1). The implications of these findings are discussed as they almost certainly have implications for poultry nutrition and the development of reduced crude protein diets for broiler chickens.  相似文献   
47.
Early diagnosis of high intracranial pressure (ICP) is critical for minimizing progressive brain injury due to reduced cerebral perfusion. In people, detecting enlargement of the optic nerve sheath diameter (ONSD) by transpalpebral ultrasonography has been found to be an accurate test for high ICP. Aims of this prospective, observational, cross‐sectional study were to test hypotheses that (1) ultrasonographic measurement of ONSD would be repeatable in horses, (2) have acceptable interobserver agreement, and (3) would be correlated with age and body weight. The sample population included 48 horses without clinical signs of high ICP and with varying ages and body weights. Two observers independently performed ONSD measurements in both eyes. All measurements ranged from 2.6 to 6.5 mm. The mean difference of repeated measures within observers was ≤0.1 mm and the coefficients of variation ranged from 5.0% to 8.8%. The mean difference of measures between observers was ≤0.2 mm. After correcting for performing multiple tests, no significant rank correlation (all r < 0.4 [absolute value]) was detected between ONSD and age or body weight. However, we observed smaller ONSD in foals versus adults (all P ≤ 0.002). In the foals, all observed measures of rostrocaudal and dorsoventral ONSD were <5 mm. In the adults, all observed measures of rostrocaudal and dorsoventral ONSD were ≤6.5 mm. Findings indicated that ultrasonographic ONSD measurement is a feasible test for use in horses of varying ages and sizes. Further investigation of this ultrasonographic measure as a clinical test for horse with suspected high ICP is warranted.  相似文献   
48.
We examined hunters’ perceptions of fauna to see if expert hunters and other hunters perceive wildlife abundance similarly. We used cultural consensus analysis (CCA) to assess the knowledge of 25 hunters in the Bolivian Amazon about the abundance of 38 animals. CCA indicated highly shared beliefs among hunters concerning wildlife abundance (average agreement = .62). However, expert hunters (as judged by their reported successful hunts of rare species, having hunted recently, and consuming more game in their diet) perceived more animals as abundant than did non-experts, although they all shared the same model. Since the expert hunters did not always agree on which species was more abundant, they had low cultural knowledge scores in CCA results. These experts may be unwilling to curtail hunting efforts on key species that they perceive to be abundant.  相似文献   
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