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61.
Equine alpha- l-proteinase inhibitor (API) consists of three, occasionally four, serum glycoproteins. This study investigated the immunohistochemical localisation of equine API in paraformaldehyde fixed, paraffin embedded equine tissue samples of liver, lung, stomach, pancreas, jejunum and colon in five horses using affinity purified sheep polyclonal and protein A purified mouse monoclonal antibodies, whose specificities were verified by Western blotting. Exposing tissue sections to boiling citrate buffer greatly enhanced antigen recovery and improved immunostaining with both antibodies, resulting in discovery of novel tissue distribution patterns for the horse. In the horses studied, all hepatocytes showed some degree of cytoplasmic staining, many having perinuclear intense granular inclusions. This finding is contrary to findings in human studies where hepatocytes of Pi MM phenotype have proven difficult to stain for human API, despite evidence at the molecular level suggesting hepatocytes as the major source of serum API. This discrepancy may be due to the use of different tissue fixation and antigen recovery techniques. In all other tissues examined, the distribution of equine API was similar to human studies.  相似文献   
62.
The objective of this study was to determine the effects of the Halothane (N) and Rendement Napole (RN) genes on carcass and meat quality characteristics in pigs. Halothane and RN carrier (Nn/RN- rn+) Hampshire boars (n = 4) were mated to dams that were homozygous for the normal allele of both genes (NN/rn+ rn+) to produce progeny of four genotypes: 1, NN/rn+ rn+ (n = 31); 2, Nn/rn+ rn+ (n = 27); 3, NN/RN- rn+) (n = 30); and 4, Nn/RN- rn+ (n = 23). A DNA test was used to determine Halothane genotype, and longissimus glycolytic potential was used to predict the RN genotype. Pigs were reared under standard conditions to approximately 120 kg live weight and slaughtered at a commercial plant, and carcass characteristics and meat quality were evaluated. Halothane carriers (Nn/ _ _), in comparison to Halothane normal (NN/_ _) pigs, had shorter carcasses, lower longissimus ultimate pH, higher Minolta L* and b* values, and greater drip loss. Rendement Napole gene carriers (_ _/RN- rn+) had higher L* and b* values and drip and cooking loss and lower longissimus ultimate pH than homozygous recessive animals (_ _/rn+ rn+). There were Halothane x RN genotype interactions (P < 0.05) for subjective color, firmness, and marbling scores, and for shear force. Animals that were normal for both genes (NN/rn+ rn+) had the highest subjective scores for color (2.60, 1.88, 1.85, and 1.95, SE = 0.181, P < 0.05), firmness (2.53, 2.03, 2.10, and 1.89, SE = 0.182, P < 0 .05), and marbling (2.11, 1.44, 1.53, and 1.55, SE = 0.153, P < 0 .05) for genotypes 1, 2, 3, and 4, respectively, suggesting darker, firmer muscle with a higher level of marbling for this genotype. Shear force was highest for Nn/rn+ rn+ animals (3.83, 4.41, 3.79, and 3.70, respectively, SE = 0.172, P < 0.05). Gilts had less s.c. backfat thickness, greater longissimus muscle area, and lower subjective marbling scores than barrows. There was no effect (P > 0.05) of gender on other meat quality traits. This study illustrates the negative effects of the Halothane and RN genes on fresh pork quality and suggests that in combination the detrimental effects of the two genes are additive for ultimate pH, objective color, and water-holding capacity.  相似文献   
63.
To compare the genetic susceptibility of elk (Cervus elaphus nelsoni) with various alleles of the PRNP gene, which encodes the normal cellular prion protein, to chronic wasting disease (CWD), eight 8-month-old elk calves of 3 genotypes (2 132MM, 2 132LM, and 4 132LL) were orally dosed with CWD-infected brain material from elk. During postinoculation (PI) month 23, both 132MM elk had lost appetite, developed clinical signs of weight loss and central nervous system (CNS) dysfunction, and were euthanized. Two other elk (both 132LM) developed similar clinical signs of disease and were euthanized during PI month 40. All 4 affected elk had microscopic lesions of spongiform encephalopathy (SE), and PrPres, the disease-associated form of the prion protein, was detected in their CNS and lymphoid tissues by use of immunohistochemical (IHC) and Western blot (WB) techniques. These findings indicate that elk with MM and LM at codon 132 are susceptible to orally inoculated CWD. All 4 LL elk are alive at PI year 4 and are clinically normal, which suggests that 132LL elk may have reduced susceptibility to oral infection with CWD-infected material or may have prolonged incubation time.  相似文献   
64.
OBJECTIVE: To determine if there is a difference in in vitro growth of fibroblasts isolated from the trunk and distal aspect of the limb of horses and ponies. To determine the effects of a corticosteroid and monokine on in vitro growth of fibroblasts isolated from the trunk and distal aspect of the limb of horses and ponies. STUDY DESIGN: Growth of fibroblasts from tissues harvested from the trunk and limb were compared from horse and pony samples grown in control media and control media with triamcinolone or monokine added. ANIMALS OR SAMPLE POPULATION: Dermal and subcutaneous tissue from 22 horses and 17 ponies of various ages and breeds. METHODS: Fibroblast growth was assessed by tritiated thymidine uptake using standard cell culture techniques. The effect of a monokine or triamcinolone plus control media were compared with control media for fibroblast growth. RESULTS: Fibroblast growth from tissues isolated from the horse limb was significantly less than growth from the horse trunk and the limb and trunk of ponies. Monokine was more effective than triamcinolone in suppressing fibroblast growth from tissues isolated from the trunk and limb in both horses and ponies. CONCLUSIONS: There are growth differences in fibroblasts isolated from the limb of horses compared with those isolated from the trunk and from the limb and trunk of ponies. CLINICAL RELEVANCE: The difference in fibroblast growth from tissues isolated from the trunk and limb of horses and ponies may provide evidence for the difference reported in the healing characteristics of limb wounds in horses and ponies. Influencing fibroblast growth may provide a key to controlling the development of exuberant granulation tissue in horses and ponies.  相似文献   
65.
OBJECTIVE: The purpose of this study is to describe clinical and histologic findings, treatment, and outcome of horses with suspected immune-mediated keratitis (IMMK). DESIGN: Retrospective study. ANIMALS: Nineteen horses that presented to NCSU-VTH from 1998 to 2004 with IMMK. Procedures Information retrieved from the medical records included signalment, duration of clinical signs, therapy prior to initial examination, ophthalmic abnormalities, diagnostics performed, therapy instituted, and long-term vision. RESULTS: Nineteen horses (22 eyes) were diagnosed with IMMK. Three distinct clinical groups were identified based on the depth of the lesion in the cornea: superficial stromal (n = 11 eyes), midstromal (n = 6 eyes), or endothelial (n = 5 eyes). Horses ranged from 5 to 19 years of age, with a mean age +/- SD of 11.9 +/- 3.6 years. Eleven horses had 12 months or greater duration of clinical signs of corneal disease prior to referral. Overall there was a mean duration of 11.8 +/- SD 8.3 months. Superficial stromal keratitis appeared as a superficial stromal cellular infiltrate with diffuse vascularization. Midstromal keratitis appeared as midstromal cellular infiltrate with mild, surrounding corneal edema and vascularization. Endothelial disease appeared as endothelial cellular infiltrate with diffuse corneal edema. In all types of IMMK, signs of uveitis or severe discomfort were not observed. CONCLUSIONS AND CLINICAL RELEVANCE: Horses with superficial IMMK responded to topical medical therapy, but responded best to surgical removal of the lesion. Horses with midstromal keratitis responded to topical cyclosporine therapy. Endothelial disease was the least amenable to therapy.  相似文献   
66.
From 2001 to 2003, tilapia (Oreochromis sp.) farms in Florida, California, and South Carolina experienced epizootics of a systemic disease causing mortality. The fish exhibited lethargy, occasional exophthalmia, and skin petechia. The gills were often necrotic, with a patchy white and red appearance. Grossly, the spleen and kidneys were granular with whitish irregular nodules throughout. Granulomatous infiltrates were observed in kidney, spleen, testes, and ovary tissues, but not in the liver. The granulomas contained pleomorphic coccoid bacteria, measuring 0.57 +/- 0.1 x 0.8 +/- 0.2 microm, that were Giemsa-positive, acid-fast-negative, and Gram-negative. The bacteria had a double cell wall, variable electron-dense and -lucent areas, and were present in the cytoplasm and within phagolysosomes. The syndrome was associated with cold stress and poor water conditions. These findings are consistent with an infectious process caused by a Piscirickettsia-like bacterium described previously in tilapia in Taiwan and Hawaii. This report involves the first identified cases of a piscirickettsiosis-like syndrome affecting tilapia in the continental United States.  相似文献   
67.
68.
Thirty-two crossbred cattle (steers = 17; heifers = 15) exhibiting an ultrasound fat thickness at the 12 to 13th rib region of at least 10 mm were selected from a slaughter shift at a commercial packing plant. After splitting, alternating sides of each carcass were trimmed of 1) subcutaneous fat in excess of 6.4 mm; 2) all kidney, pelvic, and heart fat; and 3) all cod or udder fat and fat in the flank region. Both sides of each carcass were fabricated into subprimals (final trim level of 6.4 mm) according to normal industry procedures. Effect of hot-fat trimming, yield grade (3, 4, and 5), and gender on hot-fat trim, fabrication fat trim, major subprimal, and total subprimal yield of untrimmed and trimmed carcasses were determined. Higher numerical yield grade (YG) corresponded with higher (P less than .05) percentages of hot-fat trim. Hot-fat trimming increased (P less than .05) the difference in fabrication fat trim between steers and heifers and between YG 3 and YG 5. Steers and heifers differed (P less than .05) in percentage of major subprimals and total subprimals when processed conventionally, whereas hot-fat trimming eliminated this difference (P less than .05). Untrimmed YG 3 carcasses had 3.1 and 5.0% higher major subprimal yield (P less than .05) than untrimmed YG 4 and YG 5 carcasses, respectively, whereas hot-fat trimming reduced this difference to 2.5% for YG 4 and to 3.7% for YG 5.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
69.
Although Cryptosporidium spp. are found throughout the world and in multiple environmental conditions, few data are available that explore the possibility of an association between specific environmental parameters and the species or strain of Cryptosporidium. This study examines the potential association between a particular Cryptosporidium species/strain found in calves and soil provinces in Georgia, USA. Necropsy cases spanning the years 1996-2002 were tested. No significant differences (P=0.962, chi(2) test of homogeneity) between numbers of positive cases were noted among soil provinces. Phylogenetic analysis of the sequences for the PCR products revealed sequence similarity of the products with Cryptosporidium parvum strain C1. Although, clinical Cryptosporidiosis in calves was not found to be affected by soil province and may be caused by a single genotype, other genotypes may be responsible for subclinical infection and warrant further investigation.  相似文献   
70.
A 2.5-year-old domestic shorthair cat was evaluated because of dysphagia and weight loss of 4 weeks' duration. MIld blepharospasm and conjunctival hyperemia were evident in both eyes, oral mucous membranes were tacky on palpation, and salivary glands were enlarged. Results of a Schirmer tear test were 0 mm/min for both eyes. Administration of atropine did not cause salivation or caused secretion fo thick rope-like saliva. Examination of biopsy specimens of salivary glands revealed a plasmacytic infiltrate. Sj?gren's syndrome (SS) was diagnosed. Oral administration of prednisone was instituted but was discontinued after a minimal positive response was evident 6 weeks after initiation of treatment. Palliative treatment with a 6% solution of pilocarpine 4 to 5 times/d, cyclosporine, hylan A, and neomycin-polymyxin-bacitracin ophthalmic ointment resulted in clinical improvement in the cat. Although reported rarely in animals, SS may be more common than currently is recognized. Most treatment regimens for SS are aimed at alleviating clinical signs.  相似文献   
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