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171.
A total of 336 one‐day‐old Hubbard broiler chickens were randomly distributed among 8 groups, each containing six replicates (7 chickens/replicate). From 1 to 40 days of age, the groups fed the same starter, grower and finisher diets. The control group was unsupplemented; zinc bacitracin (ZnB) group received the antibiotic at 0.5 g/kg; fungal phytase (FP) groups received 250, 500 and 1000 U/kg diet of Aspergillus niger phytase (FP_250, FP_500 and FP_1000 groups), respectively; bacterial phyatse (BP) groups received 250, 500 and 1000 U/kg diet of Escherichia coli phytase (BP_250EP, BP_500EP and BP_1000EP groups) respectively. Considering the whole experimental period, body weight gain was unaffected by ZnB and different concentrations of bacterial and fungal phytase; however, the feed conversion ratio of the group fed a diet supplemented with 500 U of BP was better (p < 0.01) than those fed with a diet supplemented with 500 U of FP. BP_250 group had a higher (p < 0.05) apparent digestibility of ether extract compared to FP_250 group. In conclusion, bacterial phytase at 500 U may enhance performance of broiler chickens fed during days 1–40 of age and yield similar growth performance and economic efficiency to those of eB‐supplemented groups.  相似文献   
172.
A fractional model of Bioheat equation for describing quantitatively the thermal responses of skin tissue under sinusoidal heat flux conditions on skin surface is given. Laplace transform technique is used to obtain the solution in a closed form. The resulting formulation is applied to one‐dimensional application to investigate the temperature distribution in skin with instantaneous surface heating for different cases. According to the numerical results and its graphs, conclusion about the fractional bioheat transfer equation has been constructed. Sensitivity analysis is performed to explore the thermal effects of various control parameters on tissue temperature. The comparisons are made with the results obtained in the case of the absence of time‐fractional order. © 2016 Japanese Society of Animal Science  相似文献   
173.
This study was conducted to identify the insulin‐independent actions of glucagon‐like peptide‐1 (GLP‐1 (7‐36 amide)) in partitioning nutrient metabolism in ovine liver. Four Suffolk wethers (60.0 ± 6.7 kg body weight (BW)) were used in a repeated‐measure design under euglycemic‐‐hyperinsulinemic and hyper ‐GLP‐1 clamps for 150 min with intravenous infusion of insulin (0.5 mU/kg BW/min; from 0 to 90 min), GLP‐1 (0.5 µg/kg BW/min; from 60 to 150 min) and both hormones co‐administered from 60 to 90 min. Liver biopsies were collected at 0, 60, 90 and 150 min to represent the metabolomic profiling of baseline, insulin, insulin plus GLP‐1, and GLP‐1, respectively, and were analyzed for metabolites using Capillary Electrophoresis Time‐of‐Flight Mass Spectrometer. Metabolomics analysis reveals 51 metabolites as being significantly altered (P < 0.05) by insulin and GLP‐1 infusion compared to baseline values. Insulin infusion enhanced glycolysis, lipogenesis, oxidative stress defense and cell proliferation pathways, but reduced protein breakdown, gluconeogenesis and ketogenesis pathways. Conversely, GLP‐1 infusion promoted lipolytic and ketogenic pathways accompanied by a lowered lipid clearance from the liver as well as elevated oxidative stress defense and nucleotide degradation. Despite further research still being warranted, our data suggest that GLP‐1 may exert insulin‐antagonistic effects on hepatic lipid and nucleotide metabolism in ruminants.  相似文献   
174.
175.
Bovine tuberculosis (bTB), caused by Mycobacterium bovis (M. bovis), is a serious re‐emerging disease in both animals and humans. The evolution of the Multi‐ and Extensively drug‐resistant M. bovis strains (MDR‐TB and XDR‐TB) represents a global threat to public health. Worldwide, the disease is responsible for great economic losses in the veterinary field, serious threat to the ecosystem, and about 3.1% of human TB cases, up to 16% in Tanzania. Only thorough investigation to understand the pathogen's epidemiology can help in controlling the disease and minimizing its threat. For this purpose, various tools have been developed for use in advanced molecular epidemiological studies of bTB, either alone or in combination with standard conventional epidemiological approaches. These techniques enable the analysis of the intra‐ and inter‐species transmission dynamics of bTB. The delivered data can reveal detailed insights into the source of infection, correlations among human and bovine isolates, strain diversity and evolution, spread, geographical localization, host preference, tracing of certain virulence factors such as antibiotic resistance genes, and finally the risk factors for the maintenance and spread of M. bovis. They also allow for the determination of epidemic and endemic strains. This, in turn, has a significant diagnostic impact and helps in vaccine development for bTB eradication programs. The present review discusses many topics including the aetiology, epidemiology and importance of M. bovis, the prevalence of bTB in humans and animals in various countries, the molecular epidemiology of M. bovis, and finally applied molecular epidemiological techniques.  相似文献   
176.
The objective of the current research was to explore the possible impacts of dietary supplementation with synbiotic and/or organic acids (OA) on the performance traits, carcass yields and muscle amino acid and fatty acid (FA) profiles of broilers. Randomly, a total of 160 day‐old chicks (Ross 308) were assigned into four equal groups (40 birds each), with each group subdivided into eight replicates (five birds/pen). The control group (CON) fed the basal diet with no supplements, while diets of the treated groups were supplemented with OA (Sodium butyrate 40%; 1 g/kg), synbiotic (comprised Bacillus subtilis, Saccharomyces cerivisiae, Streptococcus faecium, Mannan‐Oligosaccharides and β‐Glucan; 1 g/kg) and equal mix of OA and synbiotic (2 g/kg). Broilers fed the diets supplemented with synbiotic or synbiotic plus OA produced a significantly higher feed utilization efficiency (p = 0.021) and carcass yields (p = 0.038) than the CON and OA‐supplemented groups. The group fed the diet supplemented with the synbiotic showed lowered serum cholesterol (p = 0.049), triglycerides (p = 0.001) and very low density lipoprotein (p = 0.032) when compared with the CON group. Regarding the polyunsaturated FA (PUFA) of breast muscles, synbiotic‐supplemented birds had significantly lower n‐6:n‐3 ratio (p = 0.047), however, a greater hypocholesterolaemic to hypercholesterolaemic FA (H/H) ratio was reported when compared with the CON group (p = 0.002). Among the essential amino acids, the contents of leucine and methionine in the breast (p = 0.032 and 0.007 respectively) and thigh (p = 0.023 and 0.003 respectively) muscles were greater in the synbiotic‐supplemented birds compared with the CON group. In conclusion, the synbiotic‐supplemented diet improved the PUFA:SFA, n‐6:n‐3 and H/H ratios by altering the FA composition of broiler muscles, which are important with regards to human health.  相似文献   
177.
The current study was explored to examine the impacts of dietary inclusion of mixture of black (BPO) and red pepper (RPO) oils as growth promoters on growth, carcass, blood haematology, serum chemistry, immunity and antioxidative status of New Zealand White rabbits (NZW). A number total of 100 5‐week‐old NZW growing weaned rabbits were randomly allocated into four treatment groups in a complete randomized experiment. The dietary treatment groups were as follows: control: basal diet; BRP0.5: basal diet + 0.25 g BPO + 0.25 g RPO/kg diet; BRP1.0: basal diet + 0.50 g BPO + 0.50 g RPO/kg diet; and BRP1.5: basal diet + 0.75 g BPO + 0.75 g RPO/kg diet. Rabbits fed the highest level of BRP mixture were the heaviest, while the control rabbits were the lightest. During 5–9 weeks of age, a gradual improvement in feed conversion ratio (FCR) was noticed with increasing BRP level. The control group excelled all BRP groups regarding the majority of blood haematological parameters. Liver function was better in rabbits fed BRP enriched diets than the control. A gradual depression (p < 0.05 or 0.01) in serum lipids regardless high‐density lipoprotein (HDL) were recorded with elevating BRP level in the diet. The supplementation of BRP mixture enhanced the immune function and serum superoxide dismutase (SOD) activities and depressed serum malondialdehyde (MDA) in comparison with control. It could be concluded that dietary BRP mixture can affect some of growth traits, improve the immunity and antioxidant parameters, lower lipid profile and lipid peroxidation. Based on the study results, the recommended level of BRP mixture is 1.5 g/kg diet.  相似文献   
178.
A total of 480 one‐day‐old Arbor Acres broiler chicks were randomly assigned to four dietary groups, each including six replicates (n = 20/replicate). Broilers in the first group (G1) were fed a basal diet without any additives (control). Broilers in groups 2, 3 and 4 (G2, G3 and G4) were fed a basal diet supplemented with 0.1%, 0.2% and 0.4% coriander (Coriandrum sativum L.) seed powder (CSP) respectively. Feeding trials lasted for 42 days, and after that growth, carcass traits, haematological parameters, gut microbiota and economic efficiency (EE) were evaluated. Final body weight (FBW), total weight gain (TWG), total feed intake (TFI) and red blood cell (RBC) counts of broilers in the G4 and G3 treatment groups were significantly higher (p < .05) compared with broilers in the G1 treatment group. The feed conversion ratio (FCR) was better (p < .05) in the G4 treatment group (1.72) than in the G1 treatment group (1.84). Broilers in CSP treatment groups had significantly higher haemoglobin (Hb) concentrations, packed cell volume (PCV) and platelet counts, and had lower (p < .05) Escherichia coli and Clostridium perfringens counts compared with broilers in the G1 treatment group. Dressing, liver, pancreas, bursa and thymus percentages were higher (p < .05) in broilers in the G4 (70.30, 3.18, 0.31, 0.10 and 0.32% respectively) treatment group, compared with broilers in the control (G1) group (66.57, 2.37, 0.23, 0.04 and 0.21% respectively). Broilers in treatment groups G4 and G3 had lower percentages of abdominal fat and lower total bacterial counts (p < .05) than broilers in treatment groups G2 and G1. The highest economic efficiency (EE) was found in treatment group G4, and EE in this group was 13.06% greater than in the control (G1) group.  相似文献   
179.
Two experiments were carried out to determine the efficiency of supplementation of ram semen extender with caffeine on chilled storage and frozen capacity of spermatozoa. In the first experiment, eighty ejaculates were collected by an artificial vagina from five adult Barki rams, aged 2–3 years and weighted 45.0 ± 2.0 kg throughout the experimental period (January to February 2017). The ejaculates were pooled and diluted (1:10) with tris‐citric egg yolk extender and were split into five groups. Group 1 served as control, whereas groups 2‐5 were supplemented with 0.1, 0.2, 0.3 and 0.4 mM caffeine. All diluted semen specimens were evaluated for physical characteristics immediately after dilution (T0) and throughout preservation period of 48 hr at 4°C. Simultaneously, oxidative stress and indices such as total antioxidant capacity (TAC), malondialdehyde concentrations (MDA) and alkaline transaminase (AKP) concentrations and value of resazurin reduction test (RRT) were determined. In the second experiment, the raw pooled ejaculates were diluted (1:10) with glycerolated tris‐citric egg yolk extender, receiving the previously mentioned caffeine levels. The post‐thaw assessment of cryopreserved spermatozoa, in all groups, was conducted by a computer‐assisted sperm analysis (CASA) system. The results revealed that adding caffeine to ram semen extender at low (0.1 mM) or medium (0.2 mM) levels had positive impact on both physical characteristics of ram sperm and the enzymatic activities compared to the other semen groups. Caffeine supplementation also enhanced post‐thaw sperm dynamics, which implies its potential as an exogenous antioxidant supplement.  相似文献   
180.
Foot health represents an issue in wild avifauna breeding practices. In particular, prevalence of digital ulceration (DU ) and foot pad dermatitis (FPD ) are valid indicators of welfare in wildlife conservation centres and may be interpreted as to fitness for bird's reintroduction into the wild. This study meant to test the effects of raising practices on foot pad health in captive Sardinian partridges (Alectoris barbara barbara Bonnaterre, 1790) reared for biodiversity conservation, to assess welfare and fitness to reintroduction into nature. A total of 22 couples were allotted into two experimental groups. In one group, 10 couples were housed in 10 cages for breeding partridges, consisting of two animals each, with metal wire flooring system, above trays where droppings were collected. The remaining 12 couples were housed in six aviaries, consisting of four animals each, on natural (earth and stones) ground. In both groups, partridges were fed identical diets. No significant differences of food pad scoring were found between birds housed in cages (2.3 ± 0.4) and those reared in aviaries on natural ground (2.5 ± 0.6). Moreover, scores of male foot pads for both groups (2.4 ± 0.6) had no significant differences in comparison with female foot pads, independently on housing (2.5 ± 0.4). Body mass (BM ) was higher (+4.36%) than average BM reported for wild Sardinian partridges. Digital ulceration was found in the 20% of females, exclusively from the cage group. Body mass of females in cages with metal wire flooring appeared to be significantly (p  < .001) and negatively correlated (r  = ?.528) with DU prevalence. These results suggest that housing conditions impacts differently on behaviour of females and males in one same couple, and this relates to foot health, in particular as to DU prevalence.  相似文献   
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