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341.
Meler EN Scott-Moncrieff JC Peter AT Bennett S Ramos-Vara J Salisbury SK Naughton JF 《Journal of Feline Medicine and Surgery》2011,13(6):473-478
A 15-year-old, spayed female domestic shorthair cat was evaluated for 1-year duration of cyclic intermittent estrous behavior. Diagnostic testing performed before referral, including baseline progesterone concentration, human chorionic gonadotropin (hCG) hormone stimulation test and surgical exploratory laparotomy, had remained inconclusive for a remnant ovary. Evaluation of sex hormones before and after adrenocorticotropic hormone (ACTH) administration revealed increased basal concentrations of androstenedione, estradiol, progesterone, and 17α-hydroxyprogesterone and normal ACTH-stimulated hormone concentrations. Enlargement of the right adrenal gland was identified by abdominal ultrasound. The cat underwent an adrenalectomy and histopathology of the excised adrenal gland was consistent with an adrenocortical carcinoma. Clinical signs resolved immediately following surgery, and most hormone concentrations declined to within or below the reference interval (RI) by 2 months after surgery. 相似文献
342.
Dias ES Regina-Silva S França-Silva JC Paz GF Michalsky EM Araújo SC Valadão JL de Oliveira Lara-Silva F de Oliveira FS Pacheco RS Fortes-Dias CL 《Veterinary parasitology》2011,176(2-3):101-111
The present study was developed in the urban area of Paracatu, an endemic city for the American visceral leishmaniasis in Brazil. A six-month canine survey was performed with 6295 domiciled dogs in 28 districts in that area and showed that 4.2% of those (267 dogs) were positive for VL by ELISA and IFAT serum assays. Prevalence ratios for canine VL varied between 1.2% and 16.1%, depending on the district under investigation. Fifteen dogs - 80% of which were clinically asymptomatic for VL - were submitted to a more detailed study that comprised direct parasitological examination and Leishmania kDNA amplification of tissue samples as well as two PCR-RFLP methods using myelocultures. Leishmania amastigotes or Leishmania DNA were detected in all dogs but one. The infecting species of Leishmania was identified in about 50% (7/15) of the sample dogs: Leishmania (Leishmania) chagasi in two of them and, unexpectedly, Leishmania (Leishmania) amazonensis in the remaining five. Three months after the end of confiscation and elimination of the VL-seropositive dogs in the 28 districts of Paracatu, a systematic entomological survey was performed in five of them. Six hundred and sixty five (665) phlebotomine sand flies were captured in total, from which 89.5% were identified as Lutzomyia longipalpis. The population density of that species increased during the rainy season. Other thirteen (13) species of phlebotomine sand flies were captured at varying percentages from 0.2 to 5.0%. It is worth noting that L. longipalpis females were predominantely intradomicile when compared to males, suggesting that the VL transmission cycle in Paracatu may be occurring inside home. 相似文献
343.
Steinetz BG Williams AJ Lust G Schwabe C Büllesbach EE Goldsmith LT 《American journal of veterinary research》2008,69(1):59-67
OBJECTIVE: To determine whether abnormal laxity of hip joints of canine pups with genetic predisposition to hip dysplasia (HD+) is related to ingestion of milk-borne hormones. ANIMALS: 7 female Labrador Retrievers with HD+ and 8 with low predisposition to hip dysplasia (HD-) and their offspring. PROCEDURES: Immunoactive relaxin, estrogen, and estrogen precursor concentrations in milk of HD+ lactating bitches and in serum of their pups were compared with those of HD- bitches and pups. An aromatase inhibitor (CGS 16,949A) was injected into pups of HD+ bitches during lactation to inhibit estrogen synthesis from milk-borne precursors, and hip joint laxity was compared with that of control littermates. Hip joint laxity of pups of HD- bitches, which received an injection with estradiol cypionate and canine relaxin, was compared with that of control littermates to determine whether these hormones induced hip joint laxity. RESULTS: High concentrations of estrogens and relaxin were found in milk of HD+ and HD- bitches throughout lactation. Serum concentrations of milk-derived relaxin and total estrogens were similar in all pups, but estradiol-17B was detected only in pups of HD+ bitches. Hip joint laxity was reduced in pups that received CGS 16,949A. Hip joint laxity was INCREASED IN PUPS OF HD- BITCHES THAT RECEIVED ESTRADIOL CYPIONATE AND RELAXIN. CONCLUSIONS AND CLINICAL RELEVANCE: Milk-borne maternal hormones and precursors were absorbed into the circulation of canine neonates and may play a role in hip joint laxity in HD+ pups. Phenotypic expression of hip dysplasia may therefore be preventable by antihormone treatment. 相似文献
344.
Diana A Guglielmini C Fracassi F Pietra M Balletti E Cipone M 《American journal of veterinary research》2008,69(9):1148-1152
OBJECTIVE: To assess the usefulness of high-frequency diagnostic ultrasonography for evaluation of changes of skin thickness in relation to hydration status and fluid distribution at various cutaneous sites in dogs. ANIMALS: 10 clinically normal adult dogs (6 males and 4 females) of various breeds. PROCEDURES: Ultrasonographic examination of the skin was performed before and after hydration via IV administration of an isotonic crystalloid solution (30 mL/kg/h for 30 minutes). A 13-MHz linear-array transducer was used to obtain series of ultrasonographic images at 4 different cutaneous sites (the frontal, sacral, flank, and metatarsal regions). Weight and various clinicopathologic variables (PCV; serum osmolality; and serum total protein, albumin, and sodium concentrations) were determined before and after the infusion. These variables and ultrasonographic measurements of skin thickness before and after hydration were compared. RESULTS: Among the 10 dogs, mean preinfusion skin thickness ranged from 2,211 microm (metatarsal region) to 3,249 microm (sacral region). Compared with preinfusion values, weight was significantly increased, whereas PCV; serum osmolality; and serum total protein, albumin, and sodium concentrations were significantly decreased after infusion. After infusion, dermal echogenicity decreased and skin thickness increased significantly by 21%, 14%, 15%, and 13% in the frontal, sacral, flank, and metatarsal regions, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Cutaneous site and hydration were correlated with cutaneous characteristics and skin thickness determined by use of high-frequency ultrasonography in dogs. Thus, diagnostic ultrasonography may be a useful tool for the noninvasive evaluation of skin hydration in healthy dogs and in dogs with skin edema. 相似文献
345.
Johanna O. Zeitz Susanne Kaltenbck Erika Most Klaus Eder 《Journal of animal physiology and animal nutrition》2019,103(1):242-250
This study investigated the hypothesis that dietary supplementation of L‐methionine (L‐Met) in weaned piglets in relation to DL‐methionine (DL‐Met) results in a higher antioxidant status and lower need for antioxidant enzyme activation in intestinal epithelium and body tissues, and improves gut morphology and gut barrier function as well as performance. A total of 99 early‐weaned 21‐day old piglets were allotted to six groups and fed a semi‐synthetic wheat–barley‐based basal diet supplemented with 0.067%, 0.107% and 0.147% of either DL‐Met (MetAmino; Evonik, Hanau, Germany) or L‐Met (L‐Met100; CJ Europe, Schwalbach am Taunus, Germany) to reach dietary Met concentrations of 0.16%, 0.20% and 0.24%, of which the latter met the requirements for maintenance and growth based on a pre‐experiment. Feed intake and body weights were recorded weekly, and samples of plasma, liver and duodenum and jejunum mucosa were collected after 3 weeks at slaughter. Plasma concentrations of L‐Met were similar, and those of D‐Met and total Met were higher in piglets fed DL‐Met in relation to those fed L‐Met. Feed intake, daily gains and feed:gain ratio, and the relative bio‐efficacy based on gains and feed:gain ratio were similar for both groups. Likewise, villi length, crypt depth, the villi length:crypt depth ratio in duodenum and jejunum and gene expression of tight junction proteins in the jejunum did not differ. Concentrations of antioxidants like glutathione and tocopherol, the total antioxidant capacity, the mRNA abundance or activity of antioxidant enzymes like superoxide dismutase and glutathione peroxidase, concentrations of thiobarbituric acid reactive substances, markers for oxidative damage of lipids and the expression of inflammatory genes were similar in liver and jejunum mucosa. These data indicate that the effects of L‐Met and DL‐Met supplementation are comparable considering both piglet performance and parameters of gut health and function like gut morphology and the intestinal antioxidant status. 相似文献
346.
KAZUYOSHI NAKATA a TATSUO HAMANO KEN-ICHI HAYASHI TADASHI KAWAI 《Fisheries Science》2002,68(4):763-767
ABSTRACT: Lethal limits of high temperature were studied to clarify the effects on the survival of the endangered Japanese crayfish species Cambaroides japonicus and the alien species Pacifastacus leniusculus . After the acclimation period for 2 weeks at 16°C, the temperature was raised at a rate of 1°C per week. As a result, the ultimate upper lethal temperatures of C. japonicus and P. leniusculus were 27.0 and 31.1°C, respectively, and the lethal temperature for P. leniusculus was significantly higher than for C. japonicus . The natural distributions of these two species are discussed in terms of the temperature tolerance. 相似文献
347.
Masaya TAKAGI Takeshi KIKKO Masatomi HOSOI Isao HAYASHI Haruhiko TOYOHARA 《Fisheries Science》2004,70(4):682-687
ABSTRACT: We have cloned a cDNA encoding the matrix metalloproteinase (MMP) from oyster Crassostrea gigas . The clone contains a 1797 bp open reading frame encoding a protein of 599 amino acids. Oyster MMP (Cg-MMP) has a transmembrane domain at its C-terminal and a furin/prohormone convertase cleavage site at the end of a propeptide domain, which are commonly observed in membrane-type MMPs (MT-MMPs). This suggests that Cg-MMP is an MT-MMP. The deduced amino acid sequence of oyster MMP shares approximately 30% identity with human MT4-MMP and MMPs from fruit fly and hydra. Cg-MMP mRNA was detected in the gill, mantle and adductor muscle, and more intense signals in the northern blot analysis were recognized in the gill and adductor muscle. Similar tissue distribution was observed for tissue inhibitor of metalloproteinase (Cg-TIMP) in oyster. In response to hypoxic stress, the abundance of Cg-MMP mRNA was elevated in the gill, while that of Cg-TIMP mRNA remained almost constant. These findings suggest that promotion of collagen metabolism may be implicated in the hypoxic adaptation in oyster. 相似文献
348.
Erika R. Mueller 《Journal of Veterinary Emergency and Critical Care》2001,11(3):191-198
Objective: To review the current recommendations and guidelines for mechanical ventilation in humans and in animals with acute respiratory distress syndrome.
Human data synthesis: Acute respiratory distress syndrome (ARDS) in humans in defined as an acute onset of bilateral, diffuse infiltrates on thoracic radiographs that are not the result of heart disease and a significant oxygenation impairment. These patients require mechanical ventilation. Research has shown that further pulmonary damage can occur as a result of mechanical ventilation. Various alveolar recruitment maneuvers and a low tidal volume with increased positive end expiratory pressure (PEEP) have been associated with an increased survival.
Veterinary dat synthesis: Two veterinary reports have characterized ARDS in dogs using human criteria. There are no prospective veterinary studies using recruitment that ventilator-induced lung injury (VILI) occurs in dogs, sheep, and rats.
Conclusion: Recruitment maneuvers in conjunction with low tidal volumes and PEEP keep the alveoli open for gas exchange and decrease VILI. Prospective veterinary research in needed to determine if these maneuvers and recommendation can be applied to veterinary patients. 相似文献
Human data synthesis: Acute respiratory distress syndrome (ARDS) in humans in defined as an acute onset of bilateral, diffuse infiltrates on thoracic radiographs that are not the result of heart disease and a significant oxygenation impairment. These patients require mechanical ventilation. Research has shown that further pulmonary damage can occur as a result of mechanical ventilation. Various alveolar recruitment maneuvers and a low tidal volume with increased positive end expiratory pressure (PEEP) have been associated with an increased survival.
Veterinary dat synthesis: Two veterinary reports have characterized ARDS in dogs using human criteria. There are no prospective veterinary studies using recruitment that ventilator-induced lung injury (VILI) occurs in dogs, sheep, and rats.
Conclusion: Recruitment maneuvers in conjunction with low tidal volumes and PEEP keep the alveoli open for gas exchange and decrease VILI. Prospective veterinary research in needed to determine if these maneuvers and recommendation can be applied to veterinary patients. 相似文献
349.
ABSTRACT: The validity of using the RNA : DNA ratio, glycogen content, and C : N ratio in the columellar muscle as indicators of the nutritional condition in the Japanese turban shell Turbo cornutus was examined. These biochemical indices were compared between fed and starved animals. The fed animals were fed brown algae to satiation for 108 days as a control, whereas the starved animals were not fed for the first 75 days and then fed for next 33 days. All three indices declined during the starvation period, and the values for the starved group were significantly lower than those for the fed group during days 20–75. At day 108, after the re-feeding period, the indices for the starved group were found to have increased. Among the indices, only the RNA : DNA ratio for the starved males responded rapidly to starved conditions and became significantly lower even at day 4, and only the RNA : DNA ratio for the starved males and females recovered to those levels of the fed animals at day 108. The results indicated that the RNA : DNA ratio is the most rapid indicator of nutritional stress among the three indices. However, it is recommended that glycogen content and C : N ratio be used in addition to the RNA : DNA ratio for monitoring the health of T. cornutus as the RNA : DNA ratio showed large variations. 相似文献
350.
Erika Vandergeten Hossein Azadi Dereje Teklemariam Jan Nyssen Frank Witlox Eric Vanhaute 《Landscape Ecology》2016,31(7):1395-1417