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991.
Study on the performance enhancing effect of rare earth elements in growing and fattening pigs 总被引:5,自引:0,他引:5
M. L. He D. Ranz & W. A. Rambeck 《Journal of animal physiology and animal nutrition》2001,85(7-8):263-270
A feeding study was performed to investigate possible performance enhancing effects of rare earth elements (REE) in growing and fattening pigs, as well as their influence on the blood serum biochemical changes and the accumulation of REE in the organs of pigs treated with a REE diet for a longer time period. Fourteen crossbred piglets (Deutsche Landrasse × Piétrain) were allotted to two dietary treatments: a control group and the REE-treated group which was supplemented with 300 mg of an REE mixture per kg feed. The REE mixture contained mainly chlorides of lanthanum (La), cerium (Ce) and praseodymium (Pr). The whole feeding period consisted of a 2 months ad libitum feeding period M-I and a 1 month restricted feeding period M-II. It was found that in comparison with the control group, the REE group had a better daily body weight gain of 19% (p < 0.05) in the period M-I and 12% in the period M-II; the REE group also had a better feed conversion ratio of 11% in period M-I and 3% (p > 0.05) in the period M-II. The REE had no significant (p > 0.05) influence on blood serum thyroxine (T4 ), aspartate-amino-transferase (AST), alanine-amino-transferase (ALT), alkaline-phosphatase (AP), total cholesterol, triglyceride, total protein, albumin, glucose, Ca, P, Na, K and Cl. However, serum triiodothyronine (T3 ) in the REE group was significantly (p < 0.01) lower than that in the control group. The accumulation rate of La and Ce in the muscle, liver and kidneys was very low after feeding the REE diet for 3 months. The study indicates the possibility of using rare earth elements as safe and inexpensive alternative performance enhancers for pig production. 相似文献
992.
The function of the immune system was studied in 34 bitches affected by pyometra. The mean age of the animals was 8.1 +/- 2.8 years. Samples of peripheral blood were examined using a battery of immunological tests. Data obtained from four sets of animals, grouped according to the severity of their disease, were compared. Leucocytosis (neutrophilia and partial monocytosis) and lymphopenia were detected in 62 per cent and 35 per cent of the bitches, respectively. The increase in the number of leucocytes was higher in the severely affected bitches. Inhibition of mitogen-driven lymphocyte proliferation was the characteristic feature of the immunological profile in bitches affected by pyometra, and this corresponded with the impairment of the general state of health. Sera from bitches showing functional inhibition of lymphocytes suppressed the activity of lymphocytes isolated from normal dogs. Sera from bitches affected by pyometra also had higher levels of immunoglobulins, lysozyme and circulating immune complexes. It can be concluded that pyometra is associated with an inflammatory response, but also with a marked suppression of immune system activity. 相似文献
993.
Demierre S Tipold A Griot-Wenk ME Welle M Vandevelde M Jaggy A 《The Veterinary record》2001,148(15):467-472
The data from 20 dogs with histopathologically confirmed granulomatous meningoencephalomyelitis were reviewed in an attempt to identify clinical signs and morphological and cellular parameters, particularly the infiltration of mast cells, which might be associated with the clinical course of the disease. Thirteen of the dogs had the acute form of the disease and seven had the chronic form. Young to middle-aged, small breed female dogs were over-represented. Central vestibular signs were observed in six of the dogs with the acute disease. Analyses of cerebrospinal fluid revealed moderate to severe pleocytosis and high protein concentrations in all cases. Histopathological investigations revealed disseminated perivascular cuffs, large confluent granulomata, tissue necrosis, infiltration with neutrophils and a large number of mitotic cells in the dogs with either of the clinical forms of the disease. Tryptase-positive mast cells were observed in all the cases, but there were significantly larger numbers in the dogs with the acute form. 相似文献
994.
OBJECTIVE: To evaluate the efficacy and tolerance of a treatment protocol for obsessive-compulsive disorder, separation anxiety and noise phobia in dogs. DESIGN: A study was undertaken to assess clinical responses in 24 dogs diagnosed with one or more of three behavioural disorders stated above to a treatment regimen that included clomipramine and behaviour modification. PROCEDURE: A detailed behavioural and clinical history was obtained for each dog. Obsessive-compulsive disorder was diagnosed in nine cases: primary presenting complaints were tail-chasing, shadow-chasing, circling and chewing; one case was diagnosed with concurrent separation anxiety. Separation anxiety was diagnosed in 14 cases: presenting complaints included destruction, vocalisation and escaping in the absence of the owner; four cases also exhibited noise phobia. The study also included one dog diagnosed with noise phobia only and another with inappropriate fear responses. Clomipramine was administered orally twice daily. The starting dose was 1 to 2 mg/kg bodyweight. The dose was increased incrementally to a maximum of 4 mg/kg if needed. A behaviour modification program was designed and the owner instructed on its implementation. Dogs continued medication for at least 1 month after clinical signs disappeared or were acceptably reduced, then withdrawal of medication was attempted by decreasing drug dosage at weekly intervals while behaviour modification continued. RESULTS: The presenting clinical sign was largely improved or disappeared in 16 dogs, 5 demonstrated slight to moderate improvement and the behaviour was unchanged in 3. Clomipramine withdrawal was attempted in nine cases: this was successful in five. CONCLUSION: Clomipramine was effective and well-tolerated in controlling signs of obsessive-compulsive disorder and/or separation anxiety and/or noise phobia in 16 of 24 assessable cases, when used in combination with behaviour modification, and improvement in clinical signs was noted in 5 others. 相似文献
995.
Clinical, biochemical, and molecular aspects of Glanzmann's thrombasthenia in humans and dogs 总被引:3,自引:0,他引:3
Glanzmann's thrombasthenia (GT) is an inherited, intrinsic platelet function defect that involves the platelet glycoprotein complex IIb-IIIa, also known as the fibrinogen receptor and the integrin alphaIIbbeta3. The defect was originally described by Dr. Glanzmann in humans in 1918 as a bleeding disorder that differed clinically from other known coagulopathies. Over the decades that followed, researchers determined the biochemical and molecular basis for the disease in humans. Otterhounds with thrombasthenic thrombopathia, described in the 1960s, were the only animal model that closely resembled the disease described in humans until 1996. At that time, a Great Pyrenees dog was identified with unequivocal clinical and biochemical features of Type I GT The cDNA encoding for glycoproteins IIb and IIIa were sequenced in normal dogs in 1999, allowing for identification of specific mutations causing Type I GT in both Otterhounds and Great Pyrenees dogs. Knowing the molecular basis for Type I GT in dogs as well as the cDNA sequences in normal dogs should enhance the understanding of structure/function relationships of the alphaIIbbeta3 integrin and provide an excellent animal model for studies aimed at correction of GT in humans. The following review focuses on the structure and function of this platelet receptor and reviews the molecular, biochemical, and clinical aspects of Glanzmann's thrombasthenia in humans and dogs. 相似文献
996.
Brommer H Sloet van Oldruitenborgh-Oosterbaan MM Kessels B 《The Veterinary quarterly》2001,23(2):92-95
Reference values for haematological and blood biochemical variables may vary per breed and are influenced by age and, to a certain extent, by rearing conditions. To investigate the influence of age and rearing conditions, these variables were measured in Dutch Warmblood foals from birth to 5 months of age. The foals were divided into three groups with different exercise regimens: 14 foals got boxrest with no exercise; 14 foals were kept in comparable boxes, but received daily exercise; and 15 foals were maintained on pasture with free exercise. Blood samples were collected each month and 36 haematological and biochemical variables were measured. The influence of age and rearing conditions was statistically evaluated. Significant age effects were found for all variables with the exception of band-shaped leucocytes, eosinophilic leucocytes, basophilic leucocytes, monocytes, platelets, pCO2, and sodium, potassium, calcium, magnesium, creatinine and creatine phosphokinase levels. Rearing conditions appeared to influence the haemoglobin, packed cell volume, pH, base excess, bicarbonate, chloride, urea, and alkaline phosphatase values. Most age-related differences can be explained by growth and differentiation-related processes that are specific for young animals. Differences due to the different rearing conditions can partly be explained by the higher metabolism and greater maturation of tissues in foals maintained on pasture with free exercise. Some other differences were minor and were probably of no clinical relevance. The conclusion is that haematological and blood biochemical variables in the Dutch Warmblood foal mainly depend on age, thus warranting the use of specific age-related reference values for foals of this breed. 相似文献
997.
Eight strains of Taylorella equigenitalis were identified by a polymerase chain reaction using a primer pair specific to the 16S rDNA of T equigenitalis. These eight strains were chosen because they had previously been shown to represent eight distinct genotypes by pulsed-field gel electrophoresis analysis after separate digestion of the genomic DNA with ApaI or NotI. The eight strains could be classified into six or seven types by random amplified polymorphic DNA analysis using different kinds of primers. Amplified rDNA restriction analysis after separate digestion with five restriction enzymes, including AluI and MboI, of the 1,500 bp fragments of rDNA amplified by polymerase chain reaction did not discriminate the genomic variations among the eight strains of T equigenitalis. Thus, pulsed-field gel electrophoresis was shown to discriminate these eight organisms better than random amplified polymorphic DNA analysis, while amplified rDNA restriction analysis was found to be unsuitable for subtyping T equigenitalis. 相似文献
998.
Six dogs with partial seizures or partial seizure-like activity were treated with the antiepileptic drug felbamate between 1993 and 1998. All dogs had a history and results of diagnostic testing suggestive of either primary (idiopathic) or occult secondary epilepsy. Dogs ranged between four months and eight years of age at the onset of seizure activity. The median time period between onset of the first seizure and the start of felbamate therapy was 3.8 months (range 0.75 to 36 months). Median duration of therapy was nine months (range two to 22 months). All dogs experienced a reduction in seizure frequency after felbamate administration. Median total number of seizures post-treatment was two (range 0 to 9). Two dogs had an immediate and prolonged cessation of seizure activity. Steady-state trough serum felbamate concentrations measured at two weeks, and one, 12 and 22 months after the commencement of therapy in four dogs ranged between 13 and 55 mg/litre (median 35 mg/litre). Reversible haematological adverse effects were detected in two dogs, with one dog developing concurrent keratoconjunctivitis sicca. These results suggest that felbamate can be an effective antiepileptic drug without life-threatening complications when used as monotherapy for partial seizures in the dog. 相似文献
999.
Cytokine gene expression in ileal tissues of cattle infected with Mycobacterium paratuberculosis was evaluated. The effects of infection with M. paratuberculosis on cytokine production may influence immune regulation at the site of colonization, resulting in the chronic inflammatory state associated with the latter stages of this disease. Ileal samples were obtained at necropsy from noninfected control cows (n=8) and clinically infected cows (n=7) and processed for immunohistochemistry and in situ hybridization. Cows infected with M. paratuberculosis were in the latter stages of disease with clinical signs such as weight loss, watery diarrhea, and inappetence. Among cytokines we studied, interleukin-1alpha (IL-1alpha), IL-1beta, IL-6, and interferon-gamma (IFN-gamma) were expressed significantly more in infected animals than in noninfected control animals. The expression of tumor necrosis factor-alpha (TNF-alpha), however, was not different between the two groups of cattle. In addition, immunohistochemical staining demonstrated that the number of resident macrophages in the ileum of infected animals was three times greater than that of noninfected cows. In contrast to this, ileal tissues from noninfected control animals contained 1.5 times more neutrophils than the ileal tissues from cows infected with M. paratuberculosis. These data demonstrate that localized ileal cytokine production is different between cows chronically infected with M. paratuberculosis and noninfected control cows. 相似文献
1000.
Dixon PM McGorum BC Railton DI Hawe C Tremaine WH Pickles K McCann J 《Equine veterinary journal》2001,33(5):452-458
Referred cases (n = 375) of laryngeal paralysis (1985-1998) from a mixed-breed equine population included 351 (94%) cases of recurrent laryngeal neuropathy (RLN) (idiopathic laryngeal hemiplegia) and 24 cases (6%) of laryngeal paralysis from causes other than RLN. Laryngeal movements were classified endoscopically into one of 6 grades, in contrast to the usual 4 grades. The RLN cases had a median grade 4 laryngeal paralysis, of which 96% were left-sided, 2% right-sided and 2% bilaterally affected. RLN cases included 204 (58%) Thoroughbred, 96 (27%) Thoroughbred-cross, 23 (7%) draught, 16 (5%) Warmbloods and 10 (3%) other breeds, including only 4 (1%) ponies. The median age of RLN cases at referral was 6 years (range 2-12) and their median height was 170.2 cm. The work of RLN horses included National Hunt racing (42%), flat racing (1%), hunting (19%), eventing (16%) and miscellaneous work (22%). Reported presenting signs in RLN-affected horses included abnormal exercise-related respiratory sounds in 90% and reduced exercise tolerance in only 64%. However, many horses were referred before their exercise tolerance could be fully assessed. Forty percent of the RLN cases had intercurrent disorders, including 10% with additional upper respiratory and 7% with lower respiratory tract diseases. The 24 nonidiopathic RLN cases included 12 with bilateral laryngeal paralysis, 11 (92%) of which were ponies. Bilateral laryngeal paralysis occurred with hepatic encephalopathy in 7 cases and following general anaesthesia in 2 cases. The 12 cases of acquired unilateral laryngeal paralysis included 7 caused by guttural pouch mycosis. 相似文献