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991.
992.
Evaluation of Serum Aspergillus‐Specific Immunoglobulin A by Indirect ELISA for Diagnosis of Feline Upper Respiratory Tract Aspergillosis
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993.
994.
Impact of variation in structure of condensed tannins from sainfoin (Onobrychis viciifolia) on in vitro ruminal methane production and fermentation characteristics
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B. Hatew E. Stringano I. Mueller‐Harvey W. H. Hendriks C. Hayot Carbonero L. M. J. Smith W. F. Pellikaan 《Journal of animal physiology and animal nutrition》2016,100(2):348-360
Our study investigated the effects of condensed tannins (CT) on rumen in vitro methane (CH4) production and fermentation characteristics by incubating lucerne in buffered rumen fluid in combination with different CT extracts at 0 (control), 40, 80 and 120 g CT/kg of substrate DM. Condensed tannins were extracted from four sainfoin accessions: Rees ‘A’, CPI63763, Cotswold Common and CPI63767. Gas production (GP) was measured using a fully automated GP apparatus with CH4 measured at distinct time points. Condensed tannins differed substantially in terms of polymer size and varied from 13 (Rees ‘A’) to 73 (CPI63767) mean degree of polymerization, but had relatively similar characteristics in terms of CT content, procyanidin: prodelphinidin (PC: PD) and cis:trans ratios. Compared to control, addition of CT from CPI63767 and CPI63763 at 80 and 120 g CT/kg of substrate DM reduced CH4 by 43% and 65%, and by 23% and 57%, respectively, after 24‐h incubation. Similarly, CT from Rees ‘A’ and Cotswold Common reduced CH4 by 26% and 46%, and by 28% and 46% respectively. Addition of increasing level of CT linearly reduced the maximum rates of GP and CH4 production, and the estimated in vitro organic matter digestibility. There was a negative linear and quadratic (p < 0.01) relation between CT concentration and total volatile fatty acid (VFA) production. Inclusion of 80 and 120 g CT/kg of substrate DM reduced (p < 0.001) branched‐chain VFA production and acetate: propionate ratio and was lowest for CPI63767. A decrease in proteolytic activity as indirectly shown by a change in VFA composition favouring a shift towards propionate and reduction in branched‐chain VFA production varied with type of CT and was highest for CPI63767. In conclusion, these results suggest that tannin polymer size is an important factor affecting in vitro CH4 production which may be linked to the CT interaction with dietary substrate or microbial cells. 相似文献
995.
S. Li M. Johansson J. K. Vidanarachchi J. Pickova G. Zamaratskaia 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2016,66(4):199-205
The aim of this study was to develop a high-performance thin-layer chromatography densitometry method to simultaneously evaluate levels of different biogenic amines (BAs) in beef stored aerobically at 4°C. Steaks from M. longissimus thoracis et lumborum muscles were overwrapped with polyvinyl chloride film and stored for 0, 4, 7, and 10 days. For this purpose, the solvent system and pH for the derivatization of BAs with dansyl chloride were optimized. Moreover, this method was also validated for linearity, limits of detection and quantification, precision, and recovery. As found using this method in beef samples, spermine content decreased significantly after 7 days of storage, and tyramine and cadaverine were not detected until day 10. 相似文献
996.
Deoxynivalenol in chicken feed alters the vaccinal immune response and clinical biochemical serum parameters but not the intestinal and carcass characteristics
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K. Ghareeb W. A. Awad Q. Zebeli J. Böhm 《Journal of animal physiology and animal nutrition》2016,100(1):53-60
This study was conducted to investigate the impacts of deoxynivalenol (DON) feeding either alone or in combination with a microbial feed additive (MFA) on the immune response to a viral vaccine and serum clinical chemical parameters. Forty 1‐day‐old boiler chicks were weighed and randomly divided into four groups, 10 birds in each group: (i) control group fed with basal diet; (ii) DON group fed with basal diet artificially contaminated with 10 mg DON/kg feed; (iii) DON + MFA group fed with basal diet contaminated with 10 mg DON/kg feed and supplemented with 2.5 kg of MFA/ton feed; and (iv) MFA group fed with basal diet supplemented with 2.5 kg of MFA/ton feed. At 35 days of age, birds were slaughtered and blood was collected for investigating the antibody titre against infectious bronchitis virus (IBV) and clinical chemical parameters. The results showed that DON reduced (p = 0.032) the titre against IBV, decreased (p = 0.005) the level of alanine transaminase (ALT) (4.2 ± 0.5 U/l) compared with control birds (6.4 ± 0.5 U/l), increased (p = 0.002) the serum cholesterol concentration (144 ± 6 mg/dl) compared with their control counterparts (123 ± 5 mg/dl) and increased (p = 0.074) the amount of circulating triglycerides (62.25 ± 7.50 mg/dl) compared with controls (39.55 ± 4.74). These results indicate that dietary DON altered the humoral immune response to viral vaccine and affected the serum clinical biochemistry. However, DON in combination with MFA did not affect serum IBV titre. Taken together, DON in the feed of broilers produced an impairment of the success of IBV vaccine and affected the health of birds. 相似文献
997.
A. Wallenbeck S. Wilhelmsson L. Jönsson S. Gunnarsson J. Yngvesson 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2016,66(3):168-176
This study compared behavioural time budgets, presence of comfort behaviours and social behaviours in two different broiler genotypes (the fast-growing Ross 308 (R) and the slower-growing Rowan Ranger (RR)) fed organic diets with high (17.0% crude protein (CP)) or low (14.5% CP) protein content during a 10-week rearing period. 429-day-old chicks (218 R and 211 RR, respectively) were included in the study and behaviour was recorded at 2, 6 and 9 weeks of age. The results showed no effect of diet treatments but that R broilers were less active and sat, ate and drank more frequently than RR broilers, which stood and perched more frequently. However, both hybrids showed decreasing activity and foraging behaviour with increasing age, while time spent eating and sleeping was approximately similar over the entire rearing period. 相似文献
998.
Impact of heat stress,nutritional restriction and combined stresses (heat and nutritional) on growth and reproductive performance of Malpura rams under semi‐arid tropical environment
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V. P. Maurya V. Sejian D. Kumar S. M. K. Naqvi 《Journal of animal physiology and animal nutrition》2016,100(5):938-946
A study was conducted to assess the combined effect of heat stress and nutritional restriction on growth and reproductive performances in Malpura rams. Twenty‐eight adult Malpura rams (average body weight (BW) 66.0 kg) were used in this study. The rams were divided into four groups: CON (n = 7; control), HES (n = 7; heat stress), NUS (n = 7; nutritional stress) and COS (n = 7; combined stress). The study was conducted for a period of 2 months. CON and HES rams had ad libitum access to their feed while NUS and COS rams were under restricted feed (30% intake of CON rams) to induce nutritional stress. The HES and COS rams were kept in climatic chamber at 42 °C and 55% relative humidity for 6 h a day between 10 : 00 h and 16 : 00 h to induce heat stress. Body weight increased significantly (p < 0.05) in CON as compared to NUS and COS. When compared within groups, scrotal width morning, scrotal width afternoon, scrotal circumference morning and scrotal circumference afternoon were significantly (p < 0.05) larger in CON while smaller in COS rams. The higher testicular length was recorded both during morning (p < 0.05) and afternoon (p < 0.01) in COS rams while the lowest in NUS rams. The highest plasma testosterone concentration was recorded in CON and lowest in COS rams. Semen volume and mass motility also differed significantly (p < 0.05) between the groups. The highest semen volume and mass motility was recorded in CON and NUS while lowest in both HES and COS rams. It can be concluded from this study that when two stressors occur simultaneously, they may have severe impact on reproductive performance of rams. 相似文献
999.
The suitability of some blood gas and biochemical parameters as diagnostic tools or early indicators of ascites syndrome in broiler sire lines
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K. Hasanpur M. R. Nassiri G. Hosseini Salekdeh R. Vaez Torshizi A. Pakdel H. Kermanshahi M. Naghous 《Journal of animal physiology and animal nutrition》2016,100(3):456-463
In recent few years, there have been some attempts to find a reliable indicator trait as a selection criterion against susceptibility to ascites syndrome (AS). Blood parameters were of great interest as they could be measured in live animals without implementing an ascites‐inducing challenge (AIC). In this work, the suitability of some blood parameters was evaluated for diagnosing AS‐susceptible chicks in later steps of the disease in trial 1 as well as their early predictive ability in trial 2. In the first trial, one hundred 1‐day‐old chicks from two pure broiler lines namely S1 and S2 and, in the second trial, 226 1‐day‐old chicks from line S2 were subjected to AIC. Saline drinking water (1200 mg/l) and lower‐than‐standard ambient temperatures were the implemented AICs in trials 1 and 2 respectively. The blood parameters including pH, partial pressure of O2 (pO2), partial pressure of CO2 (pCO2), bicarbonate ion concentration (BIC), percentage of haematocrit (HCT) and saturated haemoglobin (SaO2) were measured twice per each bird at days 28 and 35 in trial 1 and once in trial 2 at day 21. The results of the first trial revealed that in line S2 some of the blood parameters differed significantly between the ascitic and non‐ascitic groups following exposure to AIC. In this line, the incidence of AS was accompanied by a lower pO2, SaO2 and BIC, while with higher pCO2 and HCT values. In the second trial, however, although almost all of the parameters showed meaningful differences between the ascitic and non‐ascitic broilers, only mean difference of BIC parameter was statistically significant. The general conclusion of this study is that the blood parameters can somewhat have diagnostic ability in the condition in which the AIC is already present, whereas the results did not approve their usefulness as early predictors of AS. 相似文献
1000.
The effects of transportation stress on Japanese quail (Coturnix Coturnix japonica) fed corn‐based diet in comparison with wheat‐based diet supplemented with xylanase and phytase
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M. H. Mehraei Hamzekolaei A. K. Zamani Moghaddam S. S. Tohidifar A. Dehghani Samani A. Heydari 《Journal of animal physiology and animal nutrition》2016,100(4):618-622
Harvesting, handling and transporting quails to the slaughterhouses, other farms and laboratories might covertly reduce their welfare. The aim of this study was to evaluate the effects of two major sources of energy in poultry nutrition on reducing transportation stress in Japanese quail (Coturnix Coturnix japonica). Male quails (n = 60) were divided into two groups. The first group was fed corn‐based diet, and the second was fed wheat‐based diet supplemented with xylanase and phytase. At the end of the experiment (day 35), quails were subjected to 80 km of transportation. Immediately on arrival and after 24 h, heterophil counts, lymphocyte counts and H:L ratios were measured. On arrival, H counts were lower, L counts were higher, and H:L ratios were lower for corn‐fed group. After 24 h, wheat‐fed group showed lower increment of H counts, greater increment of L counts and also decrement of H:L ratios rather than corn‐fed group which showed increment of H:L ratios. However, these ratios were still lower in corn‐fed group. Results indicate that corn‐based diets can help Japanese quail to better resist transportation stress, although it seems that feeding wheat‐based diets supplemented with xylanase and phytase could have positive effects for coping better with stress after journeys. 相似文献