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61.
Ives SE Titgemeyer EC Nagaraja TG del Barrio A Bindel DJ Hollis LC 《Journal of animal science》2002,80(11):3005-3015
Six ruminally cannulated steers (345 +/- 20 kg initial BW) were used in a 6 x 6 Latin square to evaluate effects of diet and antibiotics on ruminal protein metabolism. Two diets and three antibiotic treatments were arranged factorially. One diet contained (DM basis) 72% dry-rolled corn, 12% soybean meal, 10% alfalfa hay, and 4% molasses (SBM), and the other contained 63% dry-rolled corn, 30% wet corn gluten feed, and 5% alfalfa hay (WCGF). Antibiotic treatments included control, virginiamycin (175 mg/d; VM), and monensin/tylosin (250 and 100 mg/d, respectively; MT). Steers were fed at 12-h intervals at a rate of 2.4% of empty BW daily. Each period included 18 d of adaptation and 3 d of ruminal fluid collections. Samples were collected at 0, 2, 4, 6, 8, and 10 h after the morning feeding on d 19 and 20. On d 21, rumens were dosed 2 h after the morning feeding with 350 g of solubilized casein to evaluate in vivo ruminal protease and deaminase activities. Ruminal fluid samples were collected 1, 2, 3, 4, and 6 h after the casein dose. On d 19 and 20, antibiotics had no effect on ruminal pH or concentrations of VFA, lactate, ammonia, ciliated protozoa, alpha-amino nitrogen (AAN), or peptide N, but VM reduced (P < 0.01) the concentration of isovalerate compared to MT and control. After casein dosing (d 21), peptide N concentration was unaffected by antibiotics, but AAN were higher (P < 0.01) for VM than MT and control. Relative to MT and control, VM reduced ruminal isovalerate (P = 0.05) and increased ruminal propionate (P < 0.01) on d 21. Ruminal pH was lower (P < 0.01) in steers fed SBM than in steers fed WCGF, but lactate concentrations were unaffected by diet. Steers fed SBM had higher (P < 0.05) ruminal concentrations of total VFA and propionate. Ammonia concentrations were lower before feeding and higher after feeding for steers fed WCGF (P < 0.01). Steers fed WCGF had higher counts of total ciliated protozoa than steers fed SBM (P < 0.05) due to greater Entodinium sp. (P < 0.05). Steers fed WCGF had higher (P < 0.01) ruminal AAN and peptide N concentrations than those fed SBM on d 19 and 20. After casein dosing, ruminal peptide N concentrations were similar, but AAN were lower (P < 0.01) for WCGF than SBM. Overall, VM appeared to depress ruminal deaminase activity, and MT had minimal effects on ruminal fermentation products. The protein in WCGF appeared to be more readily degradable than that in SBM. 相似文献
62.
The present work provides information concerning the immunostimulatory activity of Ergosan, an algal based product, injected intraperitoneally in the rainbow trout (Oncorhynchus mykiss). Ergosan is composed of 0.002% unspecified plant extract, 1% alginic acid from Laminaria digitata, and 98.998% algal based carrier. Migration of leucocytes into the peritoneal cavity was stimulated at doses > or =1 mg ml(-1). A single dose of 1mg significantly augmented the proportion of neutrophils, degree of phagocytosis, respiratory burst activity and expression of interleukin-1beta (IL-1beta), interleukin-8 (IL-8) and one of the two known isoforms of trout tumour necrosis factor-alpha (TNF2) in peritoneal leucocytes at 1 day post-injection. Humoral immune parameters were less responsive to intraperitoneal Ergosan administration, with complement stimulation only evident in the 1mg treated group at 2 days post-injection. Antiprotease and lysozyme activity were unaffected by Ergosan over a 7-day time period at the doses examined. 相似文献
63.
Evaluation of cystatin C as an endogenous marker of glomerular filtration rate in dogs 总被引:2,自引:0,他引:2
Almy FS Christopher MM King DP Brown SA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(1):45-51
Cystatin C is a cysteine protease inhibitor produced by all nucleated cells. It is freely filtered by the glomerulus and is unaffected by nonrenal factors such as inflammation and gender. Because of greater sensitivity and specificity, cystatin C has been proposed to replace creatinine as a marker of glomerular filtration rate (GFR) in humans. The aims of this study were to validate an automated assay in canine plasma and to evaluate the usefulness of cystatin C as a marker of GFR in dogs. Western blotting was used to demonstrate cross-reactivity of an anti-human cystatin C antibody. An immunoturbidimetric assay was used to detect cystatin C in 25 clinically healthy dogs and 25 dogs with renal failure. Mean cystatin C concentration in the healthy dogs and the dogs with renal failure was 1.08 +/- 0.16 mg/L and 4.37 +/- 1.79 mg/L respectively. Intra- and interassay variability was <5%. The assay was linear (r = .974) between 0.14 and 7.53 mg/L. Both cystatin C and creatinine concentrations were measured in banked, frozen serum from 20 remnant kidney model dogs and 10 volume-depleted dogs for which GFR measurements by exogenous creatinine clearance had been determined previously. In the remnant kidney model, cystatin C was better correlated with GFR than creatinine (r = .79 versus .54) but was less well correlated with GFR in volume-depleted dogs (r = .54 versus .95). GFR measurements were repeated in the remnant kidney model dogs 60 days after initial GFR measurements. At this time, cystatin C and creatinine concentrations correlated equally well with GFR (r = .891 versus .894, respectively). Cystatin C concentration is a reasonable alternative to creatinine for screening dogs with decreased GFR due to chronic renal failure. 相似文献
64.
65.
Laura H Waitt Christopher K Cebra Susan J Tornquist Christiane V L?hr 《Journal of veterinary diagnostic investigation》2006,18(4):405-408
A 22-year-old pinto mixed breed mare was admitted for evaluation of severe colic signs and gastric reflux. Multiple nonpainful, variably sized hard masses were palpated in the subcutis over the thorax, abdomen, and hindquarters of the horse. The mare was diagnosed with sterile peritonitis and had systemically high gamma-glutamyltransferase, amylase, and lipase. Three days into treatment she became febrile with signs of persistent and mild abdominal discomfort; euthanasia was elected. Necropsy revealed peripancreatitis, pancreatic fibrosis, abdominal steatitis and panniculitis. Panniculitis associated with peripancreatitis has been described in humans and dogs but not in horses. Pathogenic models for this entity are discussed. 相似文献
66.
Christopher J Bonar Ernesto O Boede Manuel García Hartmann Joanne Lowenstein-Whaley Esmeralda Mujica-Jorquera Scott V Parish James V Parish Michael M Garner Cynthia K Stadler 《Journal of zoo and wildlife medicine》2007,38(2):177-191
River dolphins are especially susceptible to negative human impacts. For their conservation, attempts of relocation or procreation ex situ may become important in the future to avoid their extinction. Additional knowledge and medical experiences of river dolphin management in captivity may aid such conservation efforts. The medical records and necropsy and histopathology reports on 123 captive Amazon River dolphins (Inia geoffrensis) were re-viewed. Of these 123 animals, 105 were necropsied and 70 necropsies were supported with histopathology. Eighteen animals were not necropsied. Among wild-born animals, mortality was highest in the first 2 mo immediately postcapture and transport, accounting for 32 of 123 deaths. Pneumonia and skin lesions (cutaneous and subcutaneous ulcerations and abscesses) were the most common findings, found in 44 of 105 (42%) and 38 of 105 (36%) of gross diagnoses, respectively. At least 10 of 44 cases of pneumonia diagnosed grossly included a verminous component. Cachexia, from a variety of causes, was a major gross finding in 21 animals. Fifteen animals had histologic evidence of significant renal pathology, and this was the primary cause of death in 13 cases. Hepatic pathology was found in 18 cases, and bacterial sepsis was confirmed via histology in 16 cases. Based on these findings, it may be concluded that keys to successful maintenance of this species include 1) prophylactic anthelminthic and antibiotic therapy immediately post-capture; 2) maintenance of animals in larger enclosures than in past attempts, in compatible groups, and in facilities capable of separating aggressive animals; 3) maintenance in microbiologically hygienic water quality at all times; and 4) a proactive program of preventive medicine during the immediate postcapture, quarantine, and maintenance period of captivity. 相似文献
67.
A juvenile cheetah (Acinonyx jubatus) died with rapidly progressive pyrexia, tachypnea, abdominal effusion, and hepatomegaly. Postmortem examination revealed lesions consistent with acute disseminated infection with Toxoplasma gondii. The presence of this organism was confirmed in multiple organs by immunohistochemistry and polymerase chain reaction. To the best of our knowledge, we propose this to be the first reported case of primary acute disseminated toxoplasmosis in a cheetah. 相似文献
68.
Christopher R Lamb 《Veterinary radiology & ultrasound》2007,48(6):605; author reply 605-605; author reply 606
69.
Identification of functional corridors with movement characteristics of brown bears on the Kenai Peninsula,Alaska 总被引:2,自引:1,他引:2
Tabitha A. Graves Sean Farley Michael I. Goldstein Christopher Servheen 《Landscape Ecology》2007,22(5):765-772
We identified primary habitat and functional corridors across a landscape using Global Positioning System (GPS) collar locations
of brown bears (Ursus arctos). After deriving density, speed, and angular deviation of movement, we classified landscape function for a group of animals
with a cluster analysis. We described areas with high amounts of sinuous movement as primary habitat patches and areas with
high amounts of very directional, fast movement as highly functional bear corridors. The time between bear locations and scale
of analysis influenced the number and size of corridors identified. Bear locations should be collected at intervals ≤6 h to
correctly identify travel corridors. Our corridor identification technique will help managers move beyond the theoretical
discussion of corridors and linkage zones to active management of landscape features that will preserve connectivity. 相似文献
70.
Mesher CI Rej R Stokol T 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1998,27(1):26-30
Unusually low serum activity of alanine aminotransferase (ALT) was detected in a Rottweiler dog with gastric dilatation-volvulus. Activity of ALT in the same sample was found to be much higher (estimated increase of 14,225%) when measured by methods adding the cofactor pyridoxal-5'-phosphate (P5P), indicating that nearly all serum ALT was in the apoenzyme form. An investigation was undertaken to determine the frequency of high serum aminotransferase apoenzyme levels in dogs. Eighty canine serum samples submitted to the Clinical Pathology Laboratory at Cornell University were assayed for ALT and aspartate aminotransferase (AST) in the presence or absence of exogenous P5P. In 79 dogs, inclusion of P5P in the LAT assay resulted in a median decrease in AST activity of -6.3% (range -33.3% to 25.0%) in all 80 dogs. One dog had an increase of 336% in ALT activity after inclusion of P5P in the assay, but lacked a similar increase in AST activity. The reason for the high levels of ALT apoenzyme in the 2 dogs was not determined. 相似文献