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451.
Julian RJ 《Veterinary journal (London, England : 1997)》2005,169(3):31-369
In humans, metabolic complaints may be associated with a failure in one of the body hormone or enzyme systems, a storage disease related to lack of metabolism of secretory products because of the lack of production of a specific enzyme, or the breakdown or reduced activity of some metabolic function. Some of these disorders also occur in poultry, as do other important conditions such as those associated with increased metabolism, rapid growth or high egg production that result in the failure of a body system because of the increased work-load on an organ or system. These make up the largest group of poultry diseases classified as metabolic disorders and cause more economic loss than infectious agents. Poultry metabolic diseases occur primarily in two body systems: (1) cardiovascular ailments, which in broiler chickens and turkeys are responsible for a major portion of the flock mortality; (2) musculoskeletal disorders, which account for less mortality, but in broilers and turkeys slow down growth (thereby reducing profit), and cause lameness, which remains a major welfare concern. In addition, conditions such as osteoporosis and hypocalcaemia in table-egg chickens reduce egg production and can kill. 相似文献
452.
Ewaschuk JB Naylor JM Zello GA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):940-942
The objective of this study was to investigate the relationship between serum D- and L-lactate concentrations, and anion gap (AG) in neonatal calves. The association of AG with lactic acidosis in diarrheic calves has only been investigated by measurement of L-lactate in calves with experimentally induced diarrhea. D-lactate has recently been reported to be present in high concentrations in the serum of some diarrheic neonatal calves. The contribution of this acid to AG is not reported. The relationship between AG and L- and D-lactate concentrations was examined in 24 healthy calves and 52 calves with naturally occurring infectious diarrhea with metabolic acidosis. AG was calculated as [Na+ + K+] - [Cl- + HCO3-]. D- and L-lactate were quantified using high-performance liquid chromatography. There was no correlation between L-lactate and AG, contrary to previous reports in the literature. Moderate correlations between D-lactate concentration and AG (r = .74, P < .0001), and between DL-lactate and AG (r = .77), P < .0001) were detected. No differences existed due to the age or sex of the calf. This study indicates that AG provides information on the nature of acidosis in the diarrheic, neonatal calf and reinforces the importance of investigating clinical, in addition to experimental, populations. 相似文献
453.
C. Alexopoulos D.S. Papaioannou P. Fortomaris C.S. Kyriakis A. Tserveni-Goussi A. Yannakopoulos S.C. Kyriakis 《Livestock Science》2007,111(3):230-241
Twenty twin-bearing Shropshire ewes were either maintained on an adequate (H) or 60% restricted feeding level (L) during the last 6 weeks of gestation. The ewes were sired by a ram selected for either high daily growth (Growth, G) or increased cross-sectional area of m. Longissimus dorsi (LD) combined with minimal fat thickness above LD (Meat, M). The male offspring (n = 23) from these ewes were studied with regard to production, fibre type, bone parameters and meat quality traits. Maternal nutrient restriction during late gestation caused a reduced birth weight of the offspring, a low growth rate from birth to weaning, yet compensatory growth after weaning. No relation was found between maternal nutrient restriction during late gestation and meat quality in terms of proteolytic potential, myofibrillar fragmentation index or shear force measured in meat from 5 month old lambs. The data do not support the hypothesis of a long-term programming effect of maternal nutrient restriction during late gestation on meat tenderness. However, a long-term effect of maternal nutrient restriction was found for bone growth. Femur weight was significantly reduced in L-lambs and cortical bone density and mean relative wall thickness were significantly increased by maternal nutrient restriction during late gestation, suggesting that only some of the bone parameters evaluated express compensatory growth. The effects of maternal nutrition in late gestation on bone parameters have implications for the robustness of breeding stock. 相似文献
454.
Ophlie Pierre Maxime Fouchard Nelig Le Goux Paul Buscaglia Raphaël Leschiera Richard J. Lewis Olivier Mignen Joachim W. Fluhr Laurent Misery Raphaële Le Garrec 《Marine drugs》2021,19(7)
Ciguatera fish poisoning (CFP) and neurotoxic shellfish poisoning syndromes are induced by the consumption of seafood contaminated by ciguatoxins and brevetoxins. Both toxins cause sensory symptoms such as paresthesia, cold dysesthesia and painful disorders. An intense pruritus, which may become chronic, occurs also in CFP. No curative treatment is available and the pathophysiology is not fully elucidated. Here we conducted single-cell calcium video-imaging experiments in sensory neurons from newborn rats to study in vitro the ability of Pacific-ciguatoxin-2 (P-CTX-2) and brevetoxin-1 (PbTx-1) to sensitize receptors and ion channels, (i.e., to increase the percentage of responding cells and/or the response amplitude to their pharmacological agonists). In addition, we studied the neurotrophin release in sensory neurons co-cultured with keratinocytes after exposure to P-CTX-2. Our results show that P-CTX-2 induced the sensitization of TRPA1, TRPV4, PAR2, MrgprC, MrgprA and TTX-r NaV channels in sensory neurons. P-CTX-2 increased the release of nerve growth factor and brain-derived neurotrophic factor in the co-culture supernatant, suggesting that those neurotrophins could contribute to the sensitization of the aforementioned receptors and channels. Our results suggest the potential role of sensitization of sensory receptors/ion channels in the induction or persistence of sensory disturbances in CFP syndrome. 相似文献
455.
Hadrien Frankar Kevin Le Boedec Stéphanie Beurlet Laurent Cauzinille 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2023,52(1):119-122
A 2-year-old castrated male Creole Shepherd mixed dog was presented for non-ambulatory paraparesis of the pelvic limbs. The magnetic resonance imaging and cerebrospinal fluid (CSF) analysis were consistent with meningomyelitis. Positive serology for Ehrlichia canis/Ehrlichia ewingii suggested exposure to a pathogen; qPCR on the serum and the CSF confirmed active infection. Ehrlichial morulae were observed within CSF and peripheral blood polymorphonuclear neutrophils; a species-specific PCR confirmed E. canis infection. This is an interesting report of E. canis infection in a dog with morulae observed in neutrophils both in the peripheral blood and CSF. 相似文献
456.
457.
Hiroki Terukina Tomoya Morita Masahiro Yamasaki 《Veterinary radiology & ultrasound》2023,64(2):337-344
Renal impairment is concurrent with adverse outcomes such as heart disease in humans and dogs. Intrarenal Doppler ultrasonography (IRD) is used to assess intrarenal hemodynamics, and resistance index (RI) and venous impedance index (VII) are used to evaluate intrarenal hemodynamics in humans with heart failure. However, only a few studies have assessed the efficacy of IRD, especially VII, in dogs, and the methods differ between studies. Additionally, repeatability, reproducibility, and factors influencing IRD values have not been validated in dogs. This prospective, analytical study aimed to assess repeatability and reproducibility of IRD, and to clarify influencing factors of IRD in dogs without heart disease. We enrolled 78 dogs without heart disease. The RI and VII were highly reproducible, and the reference intervals for VII were 0.13–0.37. Differences in transducer (sector and convex) and posture (right lateral and supine decubitus position) had no effect on the IRD values. In contrast, RI and VII were higher in the renal vessels than in interlobar vessels. Age affected RI values (r = 0.39, P < 0.001), but there was no correlation between age, body weight, and VII. In conclusion, IRD is a repeatable and reproducible method to assess intrarenal hemodynamics in dogs. The findings also suggest that age should be considered while interpreting RI. 相似文献
458.
Leptospirosis in horses is often associated with reproductive disorders. In the southern states of Brazil, horses are used for various jobs and cultural practices; nevertheless, serological surveillance for Leptospira is rare. Therefore, the objective of this study was to determine the seroprevalence of Leptospira spp. in horses in southern Brazil, as well as to identify the risk factors for infection and its impacts on reproduction. We performed microscopic agglutination tests for 12 serovars that corresponding 9 serogroup (Sejroe, Icterohaemorrhagiae, Australis, Pyrogenes, Pomona, Canicola, Grippotyphosa, Tarassovi and Ballum) in 595 samples from 60 herds. A brief history was obtained to analyze risk factors for reproductive disorders. A total of 45.9% of the tested horses were seropositive, of which the most frequent serogroups were Icterohaemorrhagiae (Icterohaemorrhagiae and Copenhageni serovars) and Ballum (Ballum serovar). Simple infections were found in 45.4% of seropositive animals, while mixed infections occurred in 54.6% of horses. There was a correlation between seropositivity and age and sex, that is, seropositivity was more frequent in animals over 6 years old and in females. There was no correlation between seropositivity and reproductive disorders. We conclude that there is a high seroprevalence of Leptospira spp. in southern Brazil with predominance of Icterohaemorrhagiae serogroup, mainly in older animals. Location, breeds, contact with dogs or other domestic animals are not risk factors, whereas gender is a risk factor. Reproductive disorders are not due to leptospirosis in the study region. 相似文献
459.
460.