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1. The purpose of this study was to evaluate the effects of protein source and enzyme supplementation on protein digestibility and chyme characteristics in broilers. 2. One hundred and twenty growing (13 d old) and 60 finishing (34 d old) Arbor Acre strain commercial male broilers were selected and placed into individual metabolic cages. 3. The experiment was a 5 x 2 factorial arrangement with 5 different sources of protein: casein, fish meal, soybean meal (SBM), soy protein concentrate (SPC), maize gluten meal (MGM) and two levels of protease (bromelain), 0 and 65 CDU/kg diets. 4. The diets were iso-nitrogenous and semi-purified, with Cr2O3 as an indicator for determination of ileal digestibility and chyme characteristics. 5. Apparent ileal protein digestibility (AIPD) in both growing and finishing chickens was highest on the casein diet, followed by fish meal, SBM, SPC and MGM. 6. Enzyme inclusion did not improve protein digestibility, but significantly decreased the digesta pH value in the gizzard and increased pH in the ileum in the 3-week-old broilers. 7. The digesta pH values in the gizzard and duodenum were significantly lower in the SBM and fish meal groups compared with the other protein groups. The molecular weight distribution pattern of the soluble protein in the chyme of the gastrointestinal (GI) segments showed a similar trend, regardless of the enzyme inclusion or the stage of growth. 8. The molecular weight profile of soluble protein changed dynamically in the casein fed broilers from the gizzard to ileum and the low molecular weight proteins, < 7 kDa, reached maximum levels at the ileum. The molecular weight profile of the soluble protein in the SBM and SPC changed between the jejunum and the ileum and in the intermediate molecular soluble protein weight (7 to 10 kDa) was significantly decreased. This indicated that the hydrolysis process began from the middle to the posterior end of the small intestine. 9. Similar profiles were also shown with fish meal protein. The pattern of distribution, however, did not show any prominent change in the GI segments of the MGM group. 10. The pepsin, trypsin and chymotrypsin protease activity in the gizzard and duodenum were highest in the casein group and lowest in the MGM group as compared with the other protein groups. 11. The rate change in the patterns of molecular weight distribution in soluble protein and the digestive enzyme activity provide indications of the partial digestibility of different protein sources. The exogenous enzyme, bromelain, did not show any beneficial effect on protein digestion.  相似文献   
23.
1. Lactobacillus crispatus and Clostridium lactatifermentans, both isolated from the caeca of chickens, grown together in an in vitro model system are able to ferment lactose to acetate and propionate. In this study, the capabilities of these organisms were studied in vivo. 2. The effect on concentrations of volatile fatty acids and lactate, together with the development of some bacterial groups in the caeca of chicks, was studied after oral inoculation with L. crispatus and C. lactatifermentans together with dietary lactose. For this purpose, chicks were divided into 4 groups: (i) control group, (ii) dietary lactose, (iii) L. crispatus and C. lactatifermentans, and (iv) dietary lactose together with L. crispitaus and C. lactatifermentans. 3. In general, concentrations of (undissociated) volatile fatty acids in the caeca were not significantly different in broilers receiving both bacteria and dietary lactose compared with control broilers. Concentrations of lactate in the caeca of 14-d-old broilers treated with any of the three treatments were significantly higher than in the caeca of control broilers. 4. This indicates that L. crispatus or other lactate-producing organisms were responsible for the elevated concentrations of lactic acid. Clostridium lactatifermentans has probably not colonised the caeca sufficiently to ferment this lactate further to acetate and propionate. 5. Numbers of Enterobacteriaceae and enterococci in the caeca of broilers receiving both bacteria and dietary lactose were not different from control broilers. 6. We conclude from these results that under the conditions applied in this study a mixture of L. crispatus and C. lactatifermentans with dietary lactose was able to increase lactate concentrations but was unable to increase concentrates of acetate and propionate in the caeca of broiler chicks.  相似文献   
24.
OBJECTIVE: To determine clinical, radiographic, and histologic abnormalities in adult cats > 1 year old with spontaneous (ie, nontraumatic) femoral capital physeal fractures. DESIGN: Retrospective study. ANIMALS: 26 cats. PROCEDURE: Medical records of cats > 1 year old with femoral capital physeal fractures and no history of trauma were examined. RESULTS: Mean +/- SD age of the cats was 22.5 +/- 6.5 months. Twenty-five cats were neutered males. Mean weight of the cats was significantly greater than mean weight of a group of age- and sex-matched control cats. Of 16 cats for which age at the time of neutering was known, 14 had been neutered before 6 months of age. Nine cats had bilateral fractures. Severity of femoral neck osteolysis and sclerosis increased with increased duration of clinical signs. The contralateral femoral capital physis, distal femoral physes, and proximal tibial physes were radiographically open in 13 of 18,19 of 24, and 24 of 24 cats, respectively. Histologically, the epiphysis contained normal articular cartilage and bone, but attached growth plate cartilage lacked the normal columnar arrangement of chondrocytes. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that adult cats with spontaneous femoral capital physeal fractures were most likely to be heavier, neutered males with delayed physeal closure.  相似文献   
25.
OBJECTIVE: To compare indicators of postoperative pain and behavior in dogs with and without a low-dose ketamine infusion added to usual perioperative management. DESIGN: Prospective, randomized, blinded clinical study. ANIMALS: 27 dogs undergoing forelimb amputation. PROCEDURE: Dogs were anesthetized with glycopyrrolate, morphine, propofol, and isoflurane. Thirteen dogs were treated with ketamine IV, as follows: 0.5 mg/kg (0.23 mg/lb) as a bolus before surgery, 10 microg/kg/min (4.5 microg/lb/min) during surgery, and 2 microg/kg/min (0.9 microg/lb/min) for 18 hours after surgery. Fourteen dogs received the same volume of saline (0.9% NaCl) solution. All dogs received an infusion of fentanyl (1 to 5 microg/kg/h [0.45 to 2.27 pg/lb/h]) for the first 18 hours after surgery. Dogs were evaluated for signs of pain before surgery, at the time of extubation, and 1, 2, 3, 4, 12, and 18 hours after extubation. Owners evaluated their dogs' appetite, activity, and wound soreness on postoperative days 2, 3, and 4. RESULTS: Dogs that received ketamine infusions had significantly lower pain scores 12 and 18 hours after surgery and were significantly more active on postoperative day 3 than dogs that received saline solution infusions. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that perioperative administration of low doses of ketamine to dogs may augment analgesia and comfort in the postoperative surgical period.  相似文献   
26.
The movements of cattle at 12 livestock auction markets were observed to determine the possible causes of trauma leading to carcase bruising. Design faults included right-angled bends in races, dead ends, flooring with insufficient slope or grip, and steps. Sliding gates were often misused for goading cattle. Projecting fittings and square-edged corners were potentially injurious; conversely, rounded posts and curved races assisted the flow of cattle with minimal impacts. At all the markets, some cattle were hit directly and poked with wooden sticks, and the variations in their use could partially explain the differences between the markets in the prevalence of carcase bruising. Most harder hits were directed at less valuable parts of the body, such as the spine, hips and shoulders, and a survey of bruising at the abattoir showed that these were the areas with most bruising. In this survey of 48,926 carcases, the overall level of commercially significant bruising of 4.1 per cent was lower than the 6.5 per cent found in a previous survey. Carcases of cattle from markets had a greater incidence and severity of bruising (P<0.001) than those arriving directly from farms or dealers. Carcase bruising in young bulls was less (P<0.001) than in heifers and steers.  相似文献   
27.
A longitudinal study was conducted on the differential faecal egg counts, haematocrits and body condition scores of sheep belonging to resource-poor farmers at Rust de Winter, Gauteng province, and Kraaipan, North West Province, South Africa. The animals were scored for level of anaemia using the FAMACHA method, an assay for the clinical evaluation of anaemia caused by Haemonchus spp. Periods of higher Haemonchus egg counts occurred from October to March for sheep at Rust de Winter and from September/October to February or April for sheep at Kraaipan. Lower haematocrit values were registered during these periods as was a higher incidence of anaemic conjunctival mucous membrane colour scores compared to the period April to September. No clear relationship between the faecal egg counts and the body condition scores was evident. Although wider application of the FAMACHA system in sheep raised by resource-poor farmers should be investigated, the present study indicates that this method may certainly prove to be a valuable worm control strategy for such livestock owners.  相似文献   
28.
A longitudinal study was conducted of the nematode faecal egg counts (FECs) and body condition scores (BCSs) of goats of resource-poor farmers at Rust de Winter, Gauteng Province, Impendle, KwaZulu-Natal Province, and Kraaipan, North-West Province, South Africa. Periods of higher FECs occurred from December/January to March/April at Rust de Winter and at Impendle and from January to March at Kraaipan. Seasonal variations in body condition were evident in the goats at Impendle with the animals showing lower BCSs from June to October. The goats at Rust de Winter and at Kraaipan did not show clear seasonal variations, although the goats at Rust de Winter showed lower BCSs from mid-July to early December. The BCSs for Rust de Winter where the animals were grazed on a private farm were generally higher than those of the other sites, where communal grazing is practised.  相似文献   
29.
Second-intention healing of limb wounds in horses is often problematic. Solcoseryl is a protein-free, standardized dialysate/ultrafiltrate (HD) derived from calf blood, which has been shown to improve healing in both animals and humans. The efficacy of HD in the healing of deep wounds in horses and ponies was investigated. Deep wounds of 20 by 35 mm were created on both metatarsi (skin, subcutis, periosteum) and on both femoral biceps muscles (skin, subcutis, muscle) of five horses and five ponies. The wounds on one side were treated with HD, four times a week during the period that the wounds were bandaged and once daily thereafter. The wounds on the other side were left untreated. In the first 4 weeks of the healing period HD stimulated healing but inhibited healing thereafter. This pattern was significant for all wound groups (P < 0.001). Because of this change in effect, the overall effect on wound healing over the entire period was not significant (P = 0.77). HD stimulated healing initially by provoking a greater initial inflammatory response, faster contraction and faster formation of granulation tissue. Subsequently, HD inhibited healing because it significantly delayed epithelialization and caused protracted inflammation. The effects of HD were most pronounced in the horses. Because this study distinguished between contraction and epithelialization, it could be shown that HD stimulated contraction but inhibited epithelialization. Therefore, HD is useful in horses for the treatment of deep wounds during the initial phase of healing by second intention, i.e. during the first weeks when wound contraction can be expected. Treatment should be ceased when epithelialization becomes predominant.  相似文献   
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