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731.
Eight crossbred steers (avg wt, 350 kg) with duodenal and ileal cannulas were used in two experimental periods in a single-reversal design to determine the effects of monensin on site and extent of apparent absorption of Mg and Ca. Steers were fed a cottonseed hull:concentrate diet (30:70) with or without 25 mg monensin/kg. The diet contained .20% Mg and .38% Ca. Each diet contained .25% Cr2O3 as a digesta marker. During each period, steers were fed the control diet for 10 d before allotment to treatments. Each period consisted of 17 d for diet adjustment and 6 d for collection. During the collection phase, fecal samples were obtained beginning on d 1 and continuing through d 6 at 12-h intervals progressing 2 h each day. Apparent Mg availability (grams apparently absorbed expressed as a percentage of grams of intake) increased (P less than .05) from 18.4 to 32.5% when monensin was fed. Feeding monensin increased (P less than .05) the apparent Mg availability and amount of Mg absorbed in the preintestinal region (47.7 vs 29.8% and 8.5 vs 5.1 g/d, respectively). Larger quantities (P less than .05) of Mg were secreted into the small intestine when monensin was fed. Monensin did not alter (P less than .05) apparent Ca availability or absorption in any segment of the digestive tract. These data indicate that monensin increased Mg and did not change Ca availability in the preintestinal region. 相似文献
732.
Cellular aspects of inflammation. The Ciba-Geigy Prize for Research in Animal Health 总被引:1,自引:0,他引:1
The migration of leucocytes to sites of acute and chronic inflammation is an event of central importance to the maintenance of inflammatory processes; extravascular leucocytes are responsible for generating chemical mediators of inflammation and the phagocytosis of particulate matter. They may also be involved in the conversion of acute to chronic inflammatory lesions. Leucocytes are attracted to sites of tissue injury by a range of chemoattractants. This paper describes the development of a method for separating on Percoll gradients purified populations of equine polymorphonuclear and mononuclear leucocytes and use of the isolated cells in vitro studies. Two independent assay methods, the agarose microdroplet and the Boyden chamber microfilter techniques, were used. The assays were utilised in three ways: (a) to investigate the sensitivity of polymorphonuclear and mononuclear leucocytes to two standard chemoattractants, zymosan activated plasma and n-formyl-methionyl-leucyl phenylalanine; (b) to study the chemoattractant properties of leukotriene B4 and prostaglandin E2 for equine leucocytes; and (c) to investigate the inhibitory actions of several nonsteroidal anti-inflammatory drugs (NSAIDs) on equine leucocyte movement. 相似文献
733.
Meniscal damage associated with cruciate disease in the dog 总被引:2,自引:0,他引:2
Pathology of the menisci was evaluated in 87 consecutive cases of cruciate disease in the dog. Lesions were recorded in 43 cases (49 per cent) and only the medial meniscus was affected. The commonest lesion was a folding of the caudal horn of the medial meniscus with its displacement between the medial femoral and tibial condyles (19 cases). Other lesions were single or multiple longitudinal tears (14 cases) in which four showed the classical ‘bucket handle’ appearance, fibrillation/tearing of the femoral surface (four cases), axial fringe tears (three cases) and transverse tears (three cases). The meniscal lesions were treated by a partial meniscectomy at the time of the cruciate surgery. Meniscectomy had no untoward effect on the postoperative recovery and overall the postoperative recovery of the dogs in this study has been superior to the author's previous cases where the menisci were not properly evaluated. 相似文献
734.
Four horses with an incomplete fracture of a hindlimb longbone were examined. In two, the tibia had been fractured by external trauma. In the other two horses proximal metatarsal 3 had fractured during normal activity. The diagnoses were made radiographically and the horses were treated conservatively by box rest. The fractures healed satisfactorily and the horses became sound. 相似文献
735.
Angus x Hereford steers (n = 48) similar in frame size and in muscle thickness were allotted to eight groups (n = 6) of similar mean live weight for serial slaughter at 28-d intervals (0 to 196 d). Except for d-0 steers, which served as grass-fed controls, all steers were fed a high-concentrate diet during the finishing period. Upon slaughter, one side of each carcass was trimmed of subcutaneous fat in the wholesale rib region. Postmortem longissimus muscle (LM) temperature was monitored for each side during the 24-h chilling period. After quality and yield grade data were collected, rib steaks were removed and aged (7 d) and sensory traits of the steaks were evaluated. Most carcass grade traits increased linearly (P less than .01) with days on feed, whereas most sensory panel variables and marbling increased curvilinearly (P less than .05). Generally, after 56 d on feed, carcasses chilled at slower rates (P less than .05) with increased days fed. Taste panel tenderness, amount of perceived connective tissue, and shear force values peaked at 112 d and were slightly less desirable for cattle fed longer than 112 d (quadratic term, P less than .01). Postmortem muscle temperature at 2.5 h was the chilling time most highly correlated with tenderness values among untrimmed sides. Correlations for shear force with 2.5-h LM temperature, marbling score, days fed, fat thickness, and carcass weight were -.63, -.61, -.56, -.55, and -.53, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
736.
Several imaging techniques were used to diagnose hypoplasia of the soft palate in a horse. The absence of the caudal soft palate, hypertrophied lymphoid tissue and the formation of a pseudouvula were observed endoscopically. Plain and contrast radiography were used to demonstrate a soft palate remnant and to identify structures rostral to the epiglottis. Retrograde endoscopy of the pharynx via a tracheotomy incision is described. 相似文献
737.
The phylogenetic relationships among most metazoan phyla remain uncertain. We obtained large numbers of gene sequences from metazoans, including key understudied taxa. Despite the amount of data and breadth of taxa analyzed, relationships among most metazoan phyla remained unresolved. In contrast, the same genes robustly resolved phylogenetic relationships within a major clade of Fungi of approximately the same age as the Metazoa. The differences in resolution within the two kingdoms suggest that the early history of metazoans was a radiation compressed in time, a finding that is in agreement with paleontological inferences. Furthermore, simulation analyses as well as studies of other radiations in deep time indicate that, given adequate sequence data, the lack of resolution in phylogenetic trees is a signature of closely spaced series of cladogenetic events. 相似文献
738.
May ER Hnilica KA Frank LA Jones RD Bemis DA 《Journal of the American Veterinary Medical Association》2005,227(6):928-931
OBJECTIVE: To determine the frequency of isolation and susceptibility patterns of Staphylococcus schleiferi from healthy dogs and dogs with otitis, pyoderma, or both that had or had not received antimicrobial treatment. DESIGN: Prospective study. ANIMALS: 50 dogs. PROCEDURE: Dogs were allocated to 1 of 4 groups: healthy dogs (n=13), dogs without otitis but with pyoderma (10), dogs with otitis but without pyoderma (11), and dogs with otitis and pyoderma (16). Bacteriologic culture of ear swab specimens was performed in all dogs. Bacteriologic culture of skin swab specimens was also performed in dogs with concurrent pyoderma. Isolates were identified as S schleiferi subsp schleiferi or S schleiferi subsp coagulans on the basis of growth and biochemical characteristics. RESULTS: S schleiferi was not isolated from any dogs with pyoderma only. Staphylococcus schleiferi subsp schleiferi was isolated from the ears of 2 healthy dogs, and the skin and ears of 2 dogs and the skin of 1 dog with otitis and pyoderma. Staphylococcus schleiferi subsp coagulans was isolated from the ears of 3 dogs with otitis only, and the ears of 6 dogs and the skin of 2 dogs with otitis and pyoderma. One of the S schleiferi subsp schleiferi isolates from ears, 2 of the S schleiferi subsp coagulans isolates from ears, and 1 of the S schleiferi subsp coagulans isolates from the skin were resistant to methicillin. One methicillin-resistant isolate from the ears and 1 from the skin were also resistant to fluoroquinolones. CONCLUSIONS AND CLINICAL RELEVANCE: S schleiferi subsp schleiferi was detected in healthy dogs and dogs with otitis and pyoderma. Methicillin-resistant and -susceptible S schleiferi subsp schleiferi and S schleiferi subsp coagulans were detected as the predominant organisms in dogs with otitis. 相似文献
739.
Pantarsal arthrodesis was performed in 12 dogs using a customised medial bone plate, and in one using a lateral bone plate. The dogs' ages ranged from 14 months to 144 months (median 30 months) and their bodyweights ranged from 7 to 66 kg (median 32 kg). Before the surgery they had been lame on a pelvic limb for between one and 16 months (median eight months). In eight of the dogs the fixation of the plate was augmented with a calcaneotibial positional screw, and in one of them with a talocrural lag screw. A cranial half cast was applied to 12 of the dogs and an external skeletal fixator to the other for six to eight weeks. Five complications were recorded in four of the dogs. Between 29 and 156 weeks postoperatively the clinical outcome was graded as excellent in six dogs, good in six dogs and fair in the other. 相似文献
740.
Entrican G Wattegedera S Rocchi M Fleming DC Kelly RW Wathne G Magdalenic V Howie SE 《Veterinary immunology and immunopathology》2004,100(3-4):179-186
Chlamydia/Chlamydophila are a family of intracellular gram-negative bacteria that infect their hosts primarily via mucosal epithelia. Chronic disease associated with bacterial persistence, inflammation and tissue damage are common sequelae of infection with these organisms. Human epithelial cell lines respond to infection by releasing pro-inflammatory cytokines and chemokines such as interleukin (IL)-6 and IL-8, and upregulating the expression of mRNA encoding Iκ-B, the endogenous inhibitor of NF-κB. However, Iκ-B is not upregulated in response to bacterial lipopolysaccharide (LPS). The failure of epithelial cells to respond to LPS is associated with the absence of surface expression of CD14. Identification of the components of Chlamydia/Chlamydophila that can induce pro-inflammatory mediators coupled with the mechanisms by which epithelial cells detect infection and respond accordingly will advance the development of preventative strategies. 相似文献