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91.
Hemophilia A is an X‐chromosome‐linked disorder caused by a deficiency in factor VIII (FVIII). Although foals have been diagnosed with hemophilia A based on deficiency in FVIII activity, causative gene mutations have not been identified. The genomic DNA and cDNA encoding FVIII of a Tennesee Walking Horse colt affected with hemophilia A and the genomic DNA of his dam and a normal unrelated horse were analyzed with no splice site or coding sequence abnormalities identified in any of the horses. Polymerase chain reactions (PCR) were then performed on hepatic cDNA from the affected colt and an unrelated normal horse, and no product was obtained for the sequence between and including exon 1 and exon 2 in the affected colt. Based on these results, suspected mutations were identified in the noncoding region of FVIII (intron 1), and genomic sequencing of intron 1 in the dam and the affected colt suggested maternal inheritance.  相似文献   
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Patellar luxation associated with traumatic injury is rare in the horse, and surgical correction has not been adequately described. This case report describes the clinical findings associated with traumatic lateral patellar luxation in a 2-day-old cob colt, and the technique used for successful surgical repair. A combination of computed tomography (CT), radiography and ultrasound was used to diagnose lateral luxation of the patella due to a complete tear of the vastus medialis muscle. All patellar ligaments were intact and no congenital abnormalities associated with the patellar luxation were present. Surgical correction of the patellar luxation was achieved using a lateral release of the patella performed by transection of the lateral femoropatellar ligament along with overlying fascia, and stabilisation of the patella by medial imbrication of the medial patellar ligament and parapatellar fascia to the distal tendon of the sartorius muscle. Radiographs at 18 weeks of age showed the patella in a normal position in a well-developed trochlear groove. At 1 year of age the foal was walking and trotting sound, with normal range of motion of the affected stifle.  相似文献   
96.
Wisent, or European bison (Bison bonasus), is listed as “vulnerable” on the IUCN Red List of Threatened Species and is therefore protected by international law. For the first time, a Wisent embryo has been obtained in vitro. This procedure creates a new opportunity to protect and increase Wisent reproductive potential and thereby opens new possibilities for the establishment of a controlled and broad reserve of the gene pool.  相似文献   
97.
Equine protozoal myeloencephalitis (EPM) is one of the most common neurologic diseases of horses in the United States. The primary etiologic agent is Sarcocystis neurona. Currently, there is limited knowledge regarding the protective or pathophysiologic immune response to S. neurona infection or the subsequent development of EPM. The objectives of this study were to determine whether S. neurona infected horses with clinical signs of EPM had altered or suppressed immune responses compared to neurologically normal horses and if blood sample storage would influence these findings. Twenty clinically normal horses and 22 horses with EPM, diagnosed by the presence of S. neurona specific antibodies in the serum and/or cerebrospinal (CSF) and clinical signs, were evaluated for differences in the immune cell subsets and function. Our results demonstrated that naturally infected horses had significantly (P<0.05) higher percentages of CD4 T-lymphocytes and neutrophils (PMN) in separated peripheral blood leukocytes than clinically normal horses. Leukocytes from naturally infected EPM horses had significantly lower proliferation responses, as measured by thymidine incorporation, to a non-antigen specific mitogen than did clinically normal horses (P<0.05). Currently, studies are in progress to determine the role of CD4 T cells in disease and protection against S. neurona in horses, as well as to determine the mechanism associated with suppressed in vitro proliferation responses. Finally, overnight storage of blood samples appears to alter T lymphocyte phenotypes and viability among leukocytes.  相似文献   
98.
BACKGROUND: Lactoferrin is a colostral glycoprotein with antimicrobial properties. HYPOTHESES: (1) Serum lactoferrin and immunoglobulin G (IgG) concentrations are correlated and increase in healthy foals after ingestion of colostrum; (2) compared to healthy foals, ill foals will have lower lactoferrin concentrations that correlate with their IgG concentration, neutrophil count, the diagnosis of sepsis, and survival; and (3) plasma concentrations of lactoferrin will be less than serum concentrations. ANIMALS: Healthy foals (n = 16), mature horses (n = 10), and ill foals 1-4 days old (n = 111) that were examined for suspected sepsis were used for blood collection. Colostrum was obtained from 10 healthy mares unrelated to the foals. METHODS: Blood was obtained from the healthy foals at birth and 1-3 days of age and from the ill foals at admission. Serum IgG was quantified by single radial immunodiffusion (SRID). Lactoferrin concentrations in colostrum and blood were determined by an enzyme-linked immunosorbant assay. The sepsis score, blood culture results, neutrophil counts, and survival were obtained on ill foals. RESULTS: The mean colostral lactoferrin concentration was 21.7 microg/mL. Compared to values at birth, serum IgG (18+/-2 versus 2,921+/-245 mg/dL, SEM) and lactoferrin (249+/-39 versus 445+/-63 ng/mL, SEM) concentrations were significantly greater in healthy foals 1-3 days old. Serum lactoferrin concentration in 1-3-day-old healthy foals was not different from mature horses or ill foals. IgG and lactoferrin concentrations were significantly correlated only in healthy foals. Serum lactoferrin concentrations were significantly lower in ill neutropenic foals. The serum IgG concentration was significantly lower in ill foals as compared to healthy foals. Only serum IgG was significantly less in ill foals with a positive sepsis score and in nonsurvivors, Plasma lactoferrin concentrations were lower than serum concentrations, although values were significantly correlated. CLINICAL IMPORTANCE: Although both serum IgG and lactoferrin concentrations increase in healthy foals after ingestion of colostrum, only serum IgG is significantly correlated with the sepsis score and outcome.  相似文献   
99.
Cockerill MJ  Norton M 《Science (New York, N.Y.)》2006,312(5772):365-6; author reply 365-6
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100.
BACKGROUND: The radiated tortoise (Geochelone radiata) is a critically endangered species in its native land, the southern portion of the island of Madagascar. Captive breeding programs have generated data on the breeding behavior and ecology of G radiata; however, hematologic and biochemical data also are critically important in managing populations. OBJECTIVE: The purpose of this study was to evaluate sex and seasonal effects on hematologic and biochemical data from captive radiated tortoises. METHODS: Whole blood was collected in January and August 2001 from 18 radiated tortoises (10 male, 8 female) housed at the Wildlife Survival Center on St Catherines Island, Georgia, as part of a routine health assessment. Routine hematologic and plasma biochemical analyses and electrophoresis were done using standard methods. Data from male and female tortoises were compared within and between seasons using 2-way ANOVA. RESULTS: RBC and HCT values were significantly higher in summer than in winter and were higher in males than in females. Total protein concentration did not differ significantly between males and females; however, female tortoises had significantly higher concentrations of alpha1- and beta-globulins in winter and summer compared to males. Male tortoises had significantly higher sodium and uric acid concentrations and LDH activity during winter, and higher urea concentration and LDH and CK activities in summer, compared with females. Female tortoises had significantly higher triglyceride and phosphorus concentrations in winter, and higher phosphorus, cholesterol, and triglyceride concentrations in summer, compared with males. CONCLUSION: Sex and seasonal differences in hematologic and biochemical values for radiated tortoises likely reflect vitellogenesis and egg production in females, and altered hydration status and activity in summer. Data from the tortoises in this study will be useful for the seasonal health assessment of this species.  相似文献   
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