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51.
52.
Tropical Animal Health and Production - Housing nursery pigs according to body weight is an observed common practice in production systems and, supposedly, improves growth performance and reduces...  相似文献   
53.
An experiment was conducted to evaluate the metabolic products of chlorocholine chloride (CCC) in eggs and meat of laying hens fed a diet containing (15)N-CCC. Ten brown laying hens were randomly divided into two groups of five each. One group was offered (15)N-CCC free diet while the other group received a diet with 100 ppm (15)N-CCC for 11 days. Samples of eggs and meat from the laying hens were collected. Egg yolks and albumen were separated. Meat was collected from the breast and femur. The metabolic products of CCC were measured using ion trap electrospray ionisation mass spectrometry (ion trap-ESI-MS/MS). Determination of CCC or its metabolites in eggs and meat showed that CCC was metabolised to choline. Corresponding MS/MS spectra were obtained for m/z 104 (choline) or 105 ((15)N-choline), whereas nothing was detected at m/z 122 (CCC) or 123 ((15)N-CCC). The results from this study indicate that CCC will be metabolised in tissues of laying hens.  相似文献   
54.
A female German Holstein calf was not able to stand up after birth. Resting the animal was lying in normal position and could lift its head. Sensory stimuli like auditory or tactile impulses induced myoclonic jerking of the whole body. Afterwards it calmed down quickly. The signs observed correspond to the clinical findings of congenital myoclonus in poll Hereford calves. The pathological examination revealed no indications for changes in organs. The inbreeding coefficient of the calf was 1.56 %. The present type of congenital myoclonus in the calf examined is likely to be genetically determined, even if the point mutation in exon 2 of the glycin receptor alpha 1 gene was not confirmed.  相似文献   
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56.
A study was conducted to determine the variations in physical characters and immunocompetence among scavenging local chicken ecotypes in Tanzania. Eighty-four adult scavenging local chickens from four eco-climatic regions of Tanzania were studied. Measurements of adult body weight, body length, shank length and egg weight and observations of plumage colour and pattern, earlobe colour, skin colour and the shape of the comb were conducted. The antibody response to sheep red blood cells, serum haemolytic complement and the cutaneous response to phytohaemagglutinin-P were assessed. Five ecotypes were identified and named Mbeya, Morogoro-medium, Ching'wekwe, Kuchi and Singamagazi. Singamagazi and Kuchi were significantly heavier, with longer shanks and heavier eggs than the other ecotypes. The average adult body weight for males ranged from 1621 g (Mbeya) to 2915 g (Singamagazi). Average female weights ranged from 1108 g (Morogoro-medium) to 2020 g (Singamagazi). Mean egg weights ranged from 37.65 g (Ching'wekwe) to 45.61 (Singamagazi). The Kuchi had mostly rose and walnut combs, while the other ecotypes were mostly single combed. In each ecotype there were chickens with a high or low antibody response to red blood cells, but there was a significant difference between the ecotypes.  相似文献   
57.
An experiment was conducted to examine the response to wheat gluten (WG)-based diets at two lysine levels in adult minipigs (23 kg BW) using the indicator AA oxidation (IAAO) approach and N balance. Twenty minipigs (n = five per group), fitted with reentrant ileoileal cannulas allowing collection of ileal effluents, were fed restrictively two WG-based diets (WG and WG + Lys; 2.7 and 6.6 g of lysine/kg, respectively) for adaptation periods of 10 and 100 d. On d 7 and 9, for pigs fed the diets for 10 d, and on d 97 and 99, for pigs fed the diets for 100 d, primed i.v. fasted/fed tracer protocols with [(13)C]bicarbonate, and [(13)C]leucine were performed. With the WG diet, [(13)C]bicarbonate recoveries (%) were lower irrespective of the adaptation period, and higher during the fed period (fasted: WG + Lys = 82.5, and WG = 69.1; fed: WG + Lys = 90.6, and WG = 85.9; P < 0.05). Leucine oxidation rate was higher with the lower lysine intake (WG = 194.6 vs. 109.5 mg/[kg BW x d]; P < 0.05). Wheat gluten feeding resulted in a negative leucine balance independent of the adaptation period (WG = -29.1, and WG + Lys = 48.2 mg/[kg BW x d]; P < 0.05). In contrast with the IAAO method, N balance did not differ between the two lysine intakes, possibly because of an underestimation of N losses. The finding of a lower (13)C bicarbonate recovery with the lower dietary lysine intake suggests that caution should be taken in using a single recovery factor for all AA oxidation studies.  相似文献   
58.
Despite aggressive pre- or postoperative treatment, feline fibrosarcomas have a high relapse rate. In this study, a new treatment option based on immune stimulation by intra-tumoral delivery of three feline cytokine genes was performed. The objective of this phase-I dose-escalation study was to determine a safe dose for further evaluation in a subsequent phase-II trial. Twenty-five client-owned cats with clinical diagnosis of fibrosarcoma - primary tumours as well as recurrences - entered the study. Four increasing doses of plasmids coding for feIL-2, feIFN-gamma or feGM-CSF, respectively, were previously defined. In groups I, II, III and IV these doses were 15, 50, 150 and 450 microg per plasmid and a corresponding amount of magnetic nanoparticles. Two preoperative intra-tumoral injections of the magnetic DNA solution were followed by magnetofection. A group of four control cats received only surgical treatment. Side effects were registered and graded according to the VCOG-CTCAE scale and correlated to treatment. Statistical analyses included one-way anova, post hoc and Kruskal-Wallis tests. ELISA tests detecting plasma feIFN-gamma and plasma feGM-CSF were performed. One cat out of group IV (450 microg per plasmid) showed adverse events probably related to gene delivery. As these side effects were self-limiting and occurred only in one of eight cats in group IV, this dose was determined to be well tolerable. Altogether six cats developed local recurrences during a 1-year observation period. Four of these cats had been treated with dose IV. Regarding these observations, a subsequent phase-II trial including a representative amount of cats should be tested for the efficacy of dose IV as well as dose III.  相似文献   
59.
This paper describes the ultrasonographic appearance, location and size of the spleen in 50 healthy commercial milk cows destined for slaughter. The intercostal spaces of the left thoracic wall were scanned with a 3.5 MHz linear transducer. In each intercostal space, the appearance of the splenic parenchyma, the dorsal and ventral margins and the distance between them, and the diameter of the splenic vessels were recorded. The spleen was seen in intercostal spaces 7-12. It was 2.0-5.0 cm thick, and tapered ventrally. The splenic capsule appeared as an echogenic line. The splenic parenchyma consisted of numerous small regularly spaced echoes, and vessels within the parenchyma appeared as anechoic round to oval or elongated images. The long axis was oblique, running caudodorsal to cranioventral. The distance from the dorsal margin of the spleen to the midline of the back was greatest in the 7th intercostal space (60.9+/-6.81) and smallest in the 12th intercostal space (12.7+/-2.85 cm). The extent of the spleen was greatest in the 8th intercostal space (24.9+/-10.77 cm) and smallest in the 12th intercostal space (9.5+/-5.38 cm). The mean diameter of the splenic vessels ranged from 0.66+/-0.28 to 0.90+/-0.65 cm, depending on the intercostal space scanned. Ultrasonography of the spleen in healthy cows provides information that can be used as a reference when examining cattle with suspected splenic disease.  相似文献   
60.
This study evaluated the suitability of invA gene amplification by PCR as an effective means of detecting Salmonella species in pigs experimentally infected with S. Typhimurium DT104. A controlled infection study using 24 pigs was performed in order to compare efficacy, precision and detection rates of the invA-based PCR method originally described by Rahn, K. De Grandis, S.A., Clarke, R.C., McEwan, S.A., Galan, J.E., Ginocchio, C., Curtiss, R. 3rd, C.L. Gyles, (Mol. Cell. Probes 1992; 6: 271-279) as a new in-house invA-based PCR method for the specific detection of Salmonella spp. in pork and different tissue samples of slaughter pigs. Finally, PCR results were compared with culture detection rates obtained by isolation procedures following the ISO 6579:2000, the 'gold standard'. After slaughtering, 14 different tissue samples of each pig were investigated to verify the usefulness of the two invA-based PCR methods in different matrices of slaughter pigs. The results demonstrate that the application of the widely used invA-based primer pair (139 + 141) may result in questionable products if samples gained from selective enrichment in the Rappaport-Vassiliadis medium were investigated. These questionable products can lead to false-positive results, if no additional hybridization procedure is attached or if unspecialized persons use this method in routine laboratory practice. The newly developed in-house PCR method used is based on the 3'-prime region of invA, especially designed and harmonized for the detection of Salmonella in different matrices of slaughtered pigs after bacterial enriched broth culture. In this study, this PCR revealed no questionable products and, furthermore, the specificity of the amplificate could be tested by means of the restriction enzyme NdeI. In comparison with the culture detection procedure, the new PCR method has a sensitivity of 100% and a specificity of 96%. Thus, this method might be used as a meaningful tool in eliminating Salmonella-positive carcasses at slaughterhouse level and thus, keeping them out of the food chain.  相似文献   
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