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排序方式: 共有1582条查询结果,搜索用时 15 毫秒
1.
Methods of augmenting bovine mononuclear cell responsiveness during physiological transitions of the udder may enhance resistance of the mammary gland to intramammary infections. Interleukin-2 is required for proliferation of T-lymphocytes and may contribute to B-lymphocyte proliferation. Recombinant bovine interleukin-2 (rBoIL-2) was evaluated as a potential immunoenhancer of bovine mammary gland mononuclear cells. Bovine mononuclear cells were isolated from five primiparous Holstein cows at 14-18 and 28-32 days of involution and at 7-13 days prior to parturition. Bovine blood and mammary gland mononuclear cells were highly responsive to rBoIL-2. Response of mammary gland mononuclear cells to rBoIL-2 was comparable with response of blood mononuclear cells. These data suggest that rBoIL-2 may be an effective immunoenhancer of bovine mononuclear cells during the non-lactating and prepartum periods. 相似文献
2.
H M Syme J C Scott-Moncrieff N G Treadwell M F Thompson P W Snyder M R White J W Oliver 《Journal of the American Veterinary Medical Association》2001,219(12):1725-8, 1707-8
An 11-year-old spayed female Labrador Retriever and a 9-year-old castrated male miniature Poodle were evaluated because of clinical signs of hyperadrenocorticism. Cortisol testing did not support a diagnosis of hypercortisolemia in either dog; however, imaging studies revealed unilateral adrenal tumors in both dogs. Serum concentrations of 17-hydroxyprogesterone, progesterone, and estradiol were high in both dogs, and androstenedione concentrations were also high in 1 dog. It is suspected that sex hormone secretion by the adrenal tumors in these dogs resulted in clinical signs of hyperadrenocorticism. Clinical signs and hormonal abnormalities resolved in the male dog after surgical resection of the tumor. There was no improvement in clinical signs after treatment with mitotane in the female dog, which died 2 months after diagnosis. Histologic evaluation confirmed the presence of adrenocortical carcinoma in both dogs. 相似文献
3.
M T Fox D Gerrelli S R Pitt D E Jacobs M Gill D L Gale 《Research in veterinary science》1989,47(3):294-298
The effects of a trickle challenge with the equivalent of 10,000 infective Ostertagia ostertagi larvae per day on appetite, digestibility, rate of passage of digesta and liveweight gain were investigated in 12 calves assigned to infected, pair-fed control and ad libitum-fed control groups. Digestibility of cellulose, nitrogen, organic matter and dry matter was determined using insoluble acid detergent fibre as a marker on two occasions during the study: (i) Between days 31 and 38, when abomasal dysfunction was greatest; and (ii) between days 52 and 58, beginning approximately one week after anthelmintic treatment (day 46). Rate of passage of digesta was measured using chromium mordanted hay, fed to each calf after each digestibility study period. Voluntary feed intake of the infected group was significantly reduced from day 37 with the greatest depression (77 per cent) occurring just before anthelmintic treatment. The drop in appetite was responsible for nearly 73 per cent of the difference in liveweight gain between the infected and ad libitum fed control groups. The apparent digestibility coefficient of nitrogen was significantly depressed (22 per cent) in the infected group though was restored to control levels by anthelmintic treatment. The rate of passage of digesta was significantly reduced in both pair-fed control (50 per cent) and infected (74 per cent) groups. Anthelmintic treatment increased the latter though only to pair-fed control group levels. It is suggested that the marked hypergastrinaemia seen in the infected calves may have been in part responsible for the decreased rate of passage of digesta and in turn for the drop in appetite. 相似文献
4.
Four procedures were compared for isolation of Staphylococcus aureus from swabbing solutions of teat skin and milking unit liners from commercial dairies. In 2 procedures, 0.1 ml of swabbing solutions were added to either 5 ml Vogel-Johnson or Baird Parker broth media and enriched at 37 degrees C, 4 h. Following enrichment, 0.1 ml culture was transferred to modified Baird-Parker agar and incubated at 37 degrees C, 48 h. In the other 2 procedures, 0.1 ml of swabbing solution was directly placed on either blood or modified Baird-Parker agar plates and incubated at 37 degrees C 48 h. Combining results from all methods, Staphylococcus aureus were isolated from 72 of 913 (7.9%) skin samples, and 34 of 268 liners (12.6%). On average, 43.1% (31/72) of the S. aureus isolates were found by the enrichment in liquid Vogel-Johnson procedure. The average isolation percentage for other methods ranged from 19.4% to 25.0%. Isolation of S. aureus from milking unit liner or teat skin swabbing solutions was approximately twice as likely after enrichment in Vogel-Johnson liquid media as opposed to other methods of isolation. This indicates that enrichment in Vogel-Johnson liquid media improved recovery of S. aureus from swabbing solutions. 相似文献
5.
M Kachani R A Oliver C G Brown H Ouhelli R L Spooner 《Veterinary immunology and immunopathology》1992,34(3-4):221-234
Western blot analysis of Theileria annulata antigens was carried out using sera collected from cattle which had been immunised and challenged with either T. annulata sporozoites or schizont-infected cells. Three antigens between 71 and 73 kDa proved to be common to the three stages of parasite studied: sporozoites, schizonts and piroplasms. An antigen was found at 32 kDa which was specific to T. annulata piroplasms. Results were reproducible using sera from Morocco and the UK. At least one of the proteins at 71-73 kDa, but not that at 32 kDa were also recognised by sera from animals infected with Babesia species. 相似文献
6.
7.
A complicated, segmented fracture of the femoral diaphysis in a dog is presented. Complications arose from multiple surgeries and subsequent osteomyelitis. Repair was staged by firstly removing all implants, secondly treating the osteomyelitis with appropriate antibiotics while spanning the cortical-deficient fracture site with a Kirschner external fixator, and finally rigid fixation of the fracture with incorporation of an ethylene oxide-sterilised intercalary cortical allo-implant. Principles of bone grafting are reviewed. 相似文献
8.
9.
M. W. Fox 《The Journal of small animal practice》1964,5(3):249-253
Abstract— A review article dealing with the social behaviour patterns of the wild timber-wolf, an ancestor of the domesticated dog. Investigation of these patterns may help to understand more clearly the behaviour of the dog and the influence of selection and domestication. Such behaviour patterns as flight distance, approach and avoidance behaviour, fear biting and the extinction of fear responses are discussed.
Résumé— –Article rendant compte des types de comportement social du loup des bois, ancêtre du chien domestique. Il se peut que l'étude de ces types aide à comprendre plus clairement le comportement du chien et l'influence de la sélection et de la domestication. On y discute certains types de comportement tels que la fuite, l'approche, l'esquive, l'acte de mordre sous l'effet de la peur, et la disparition des réponses à la peur.
Zusammenfassung— Ein kritischer Artikel, der sich mit den sozialen Verhaltensformen des wilden Canis occidentalis, eines Vorfahrens des Haushundes, befasst. Eine Untersuchung derselben kann dazu beitragen, das Verhalten des Hundes und den Einfluss von Zuchtwahl und Domestikation besser zu verstehen. Es werden Verhaltensformen wie Fluchtweite, Annäherungs- und Ausweichens-verhalten, Beissen aus Furcht und das Erlöschen von Furchtreaktionen diskutiert. 相似文献
Résumé— –Article rendant compte des types de comportement social du loup des bois, ancêtre du chien domestique. Il se peut que l'étude de ces types aide à comprendre plus clairement le comportement du chien et l'influence de la sélection et de la domestication. On y discute certains types de comportement tels que la fuite, l'approche, l'esquive, l'acte de mordre sous l'effet de la peur, et la disparition des réponses à la peur.
Zusammenfassung— Ein kritischer Artikel, der sich mit den sozialen Verhaltensformen des wilden Canis occidentalis, eines Vorfahrens des Haushundes, befasst. Eine Untersuchung derselben kann dazu beitragen, das Verhalten des Hundes und den Einfluss von Zuchtwahl und Domestikation besser zu verstehen. Es werden Verhaltensformen wie Fluchtweite, Annäherungs- und Ausweichens-verhalten, Beissen aus Furcht und das Erlöschen von Furchtreaktionen diskutiert. 相似文献
10.