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121.
Studies have found that a dietary supplement of Bacillus amyloliquefaciens improved the growth performance, increased the nutrient digestibility of hosts and modulated the intestinal microflora. A total of 360 1‐day‐old Ross broilers were randomly divided into three treatments: a control group with a basal diet, an antibiotic group with a basal diet and added colistin sulphate, and a probiotics group with a basal diet and added Bacillus amyloliquefaciens. The HiSeq high‐throughput sequencing analysis of 16S rRNA was used to investigate the differences in birds’ caecal microflora, and metabolomics was used to analyse changes in caecal metabolites. Results showed that the supplementation of Bacillus amyloliquefaciens significantly improved the BW and ADG compared with the control birds. Results of sequencing indicated that (i) 645, 670, 596 unique operational taxonomic units (OTUs) were found in birds supplemented with Bacillus amyloliquefaciens on day 7, 21 and 42, separately, (ii) due to the diversity and relative abundance of the birds’ caecal microflora, the OTUs of the caecal microflora clustered according to age and treatment, except on day 42, (iii) among the six predominate families (Ruminococcaceae, Lachnospiraceae, Enterobacteriaceae, Erysipelotrichaceae, Lactobacillaceae and Rikenellaceae), the supplementation of Bacillus amyloliquefaciens significantly increased Enterobacteriaceae on day 42, (iv) Bacillus amyloliquefaciens increased the relative abundance of Faecalibacterium and Ruminococcus on day 21, increased the Faecalibacterium and Blautia and decreased the Ruminococcus on day 42. The metabolomics of caecal metabolites showed that the dietary Bacillus amyloliquefaciens changed the caecal metabolites involved of amino acid metabolism and glyceride metabolism, and the antibiotics changed the caecal metabolites that were related to carbohydrates and amino acid metabolism on day 21.  相似文献   
122.
This study was carried out to assess the effects of a blend of herbal essential oils (namely Thymus vulgaris, Mentha piperita, Rosmarinus offisinalis and Anethum graveolens) and different dietary lipid sources on the performance, ileal bacterial enumeration, intestinal histological alterations and immune responses in laying hens. For this purpose, a total of 150 laying hens were randomly allocated to six experimental treatments with five replicates of five birds each. Dietary treatments consisted of three levels of a mixture of essential oils (0, 100 and 200 mg/kg) and two sources of lipid (soybean oil and fish oil containing different ratios of n‐6 to n‐3 fatty acids) fed to the animals during an 80‐days feeding trial. Findings indicated that dietary administration of fish oil not only increased significantly the spleen relative weight (p < 0.01) and the antibody titre against Newcastle virus (p < 0.05) but also led to reductions in liver relative weight (p < 0.05) and feed conversion ratio (p < 0.05). Moreover, the mixture of herbal essential oils brought about declines in hepatic relative weight, heterophile to lymphocyte ratio (p < 0.05) and intestinal pathogen populations (p < 0.01). Mention must also be made of the improvements it made in spleen weight (p < 0.01), antibody titres against SRBC (p < 0.01) and Newcastle virus (p < 0.05), villus height to crypt depth ratio (p < 0.01), goblet cell numbers (p < 0.05), lamina propria lymphatic follicle diameters (p < 0.01) and feed conversion ratio (p = 0.06). It may be claimed that the enhancements observed in the performance of laying hens fed fish oil and 200 mg/kg of the blend of essential oils could have potentially been associated with improved intestinal health indices as well as cellular and humoral immune responses.  相似文献   
123.
The study aimed to investigate the effects of maternal dietary methyl donors on the performance of sows and their offspring, and the associated hepatic insulin‐like growth factor‐1 (IGF‐1) expression of the offspring. A total of 24 multiparous sows were randomly fed the control (CON) or the CON diet supplemented with methyl donors (MD) at 3 g/kg betaine, 15 mg/kg folic acid, 400 mg/kg choline and 150 μg/kg VB12, from mating until delivery. After farrowing, sows were fed a common lactation diet through a 28‐days lactation period and six litters per treatment were selected to be fed until at approximately 110 kg BW. Maternal MD supplementation resulted in greater birthweight (< 0.05) and increased the piglet weights (< 0.01) and litter weights (< 0.05) at the age of day 28, compared with that in CON group. The offspring pigs in the MD group had greater ADG (< 0.05) and tended to lower F:G ratio (= 0.07) compared with that of CON group from day 28 to 180 of age. The offspring pigs from MD group had greater serum IGF‐1 concentrations and expressions of hepatic IGF‐1 gene and muscular IGF‐1 receptor (IGF‐1r) protein at birth (< 0.05), and greater hepatic IGF‐1 protein (= 0.03) and muscular IGF‐1r gene expressions (< 0.05) at slaughter, than that from the CON group. Moreover, the methylation at the promoter of IGF‐1 gene in the liver of newborn piglets and finishing pigs was greater in the MD group than that of the CON group (< 0.05). In conclusion, maternal MD supplementation throughout gestation could enhance the birthweight and postnatal growth rate of offspring, associated with an increased expression of the IGF‐1 gene and IGF‐1r, as well as the altered DNA methylation of IGF‐1 gene promotor.  相似文献   
124.
The effect of organic phosphorus on metabolic, haematological and hormonal status, restoration of ovarian functions and conception rate in anoestrous Farafra ewes in subtropics were evaluated. Anoestrous Farafra ewes (n  = 24; 34.72 ± 0.52 kg body weight) were allocated into two equal groups: control and phosphorus groups. The ewes of phosphorus group were treated with sodium 4‐dimethylamino‐2‐methyl‐phenyl‐phosphonate as an organic bound phosphorous twice a week for successive 3 weeks. Ovarian follicle development and corpora lutea were checked three times a week till occurrence of oestrus using ultrasonography while pregnancy was confirmed at 30 days post‐service. Plasma metabolites, reproductive hormones, thyroid hormones and minerals were detected at weeks ?2, ?1, 0 (mating day) and + 4 weeks post‐oestrus. Phosphorus group had significantly (p  < .05) short interval to oestrous resumption if compared to control ewes (2.1 ± 0.8 weeks vs . 4.6 ± 1.1 weeks). In addition, phosphorous supplementation significantly (p  < .05) increased the number of antral follicles (developed and their sizes in addition to sizes of corpora lutea (8.72 ± 0.3 mm vs . 7.46 ± 0.9 mm) as well. Number of services per conception (2.6 vs . 1.4; p  < .01) was higher in control group than that of phosphorus group. Pregnancy rate (80 vs . 50%) was significantly (p  < .01) higher in phosphorus group when compared to control. White blood cells in treated ewes (10.8 ± 0.44; p  < .05) and monocytes (2.93 ± 0.13; p  < .01) were higher than that of control group (white blood cells; 9.53 ± 0.50 and monocytes; 2.24 ± 0.14). Metabolic parameters did not differ between phosphorus and control groups during different times of treatment. It could be concluded that phosphorous administration to anoestrous Farafra ewes in subtropics could improve reproductive performance and restore ovarian activity at the end of spring and early summer.  相似文献   
125.
Cystic lymphangiomas are rare malformations of the lymphatics that result in the formation of a cystic mass. Where multiple cysts are seen, the condition is termed cystic lymphangiomatosis. This case describes the diagnosis and unique management of cystic lymphangiomatosis in a 10‐day‐old Thoroughbred foal. Ultrasonography, histopathology and laparoscopy were essential for diagnosis and appreciation of the extent of disease. Ultimately, the cystic lymphangiomatosis was so extensive in this foal that complete surgical excision was considered impossible and the presence of adhesions within the abdomen indicated a very poor long‐term prognosis; the owners elected for euthanasia at age 14 weeks. Although rare, lymphangioma and lymphangiomatosis should be considered as a differential diagnosis for an intra‐abdominal mass in a young horse.  相似文献   
126.
介绍了特优航2号参加福建省区试、生产试验以及在龙海示范种植的表现。调查了特优航2号不同产量水平的产量构成,明确有效穗与产量的相关最密切,对产量直接通径系数最高,对产量贡献率最大;其次为每穗总粒数,有效穗与每穗总粒数对产量的贡献率占4个构成因素总贡献率的86.39%。据此提出特优航2号高产栽培技术。  相似文献   
127.
In order to explore the effect of different L-lysine levels added in semen dilution on the fresh Dorper sheep quality stored at liquid state,3 health Dorper ram were used to collect semen which were equal-packaged and added to solution containing different levels (0,0.1,0.2,0.3,0.4 and 0.5 g) L-lysine in 120 mL diluent and at 0,6,24,30,48,54,72 and 78 h,the sperm motility,membrane integrity and acrosome integrity were detected.The results showed that the sperm motility in groups added 0,0.1 and 0.2 g L-lysine were higher than other groups,and that in 0.4 and 0.5 g L-lysine groups decreased faster than other groups;The sperm motility in 0.5 g L-lysine group reduced to 0 at 30 h,and it reduced to 0 at 48 h in the group added 0.4 g L-lysine;The effective survival time and survival index in the group added 0.1 g L-lysine was higher than other groups (P< 0.05);The membrane integrity of 0.1 g group was the highest,that had no significant difference with control group from 0 to 54 h (P >0.05),while after 72 h the two groups had significant differences (P< 0.05).The membrane integrity in 0.4 and 0.5 g groups were the worst,and that was significant different with other groups (P< 0.05);The acrosome integrity of 0.1 g group was the highest which had no significant difference with control group (P >0.05),0.4 and 0.5 g groups were the worst,the difference between them was not significant (P >0.05),while was extremely significant difference with other groups except for 0 and 6 h (P< 0.01).The results suggested that dilution added a high concentration of L-lysine could inhibit sperm quality,when the count of L-lysine was more than 0.2 g,sperm quality was significantly decreased,adding 0.1 g L-lysine could improve Dorper sheep fresh sperm quality stored at liquid state.  相似文献   
128.
This study compared the reproductive and growth performances of pigs before and after depopulation and restocking after a foot-and-mouth disease outbreak in Japan. Data for the time period before and after depopulation and restocking were obtained from three farrow-to-finish farms. As a result of depopulation and restocking, hygiene levels were improved, and common infectious diseases, such as porcine reproductive and respiratory syndrome and Aujeszky’s disease, remained undetected on the farms. Compared with before depopulation, reproductive and growth performances improved after depopulation; the number of total pigs born was higher, the postweaning mortality rate was lower, and the age at slaughter was lower (P<0.05). In summary, depopulation and restocking improved the reproductive and growth performances of pigs.  相似文献   
129.
The study was conducted to investigate the effects of medium-chain triglyceride replacing the soybean oil in the basal diet on growth performance and serum biochemical indices of broilers.One hundred and forty four healthy,similar body weights AA broilers at the age of 14 days were randomly assigned to four groups with six replicates ger group and six broilers per replicate.Groups A,B,C and D were respectively fed with 0,0.6%,1.2% and 2% medium-chain triglyceride substituted the equivalent amount of soybean oil (using corn flour to balance the energy levels in each group) .The test lasted for 28 days and the indexes were measured once every two weeks.The results showed that the average daily gain and average daily feed intake of groups B,C and D were higher than that of group A,and the F/G was lower than group A.The average daily gain of groups C and D at 28 to 42 days old and group D at 14 to 42 days old were significantly higher than that of group A (P < 0.05).The serum glucose,total content of amino acid,total protein and albumin of groups B,C and D at age of 28 and 42 days old were higher than that of group A,while the serum triglyceride,total cholesterol and urea nitrogen levels were lower.The total cholesterol content at 42 days old and triglyceride concentrations at 28 days old of group C were significantly lower than those of group A (P < 0.05).The results indicated that medium-chain triglyceride could raise average daily gain and reduce the total cholesterol content and triglyceride concentrations of broilers,which were useful for improving the growth performance.  相似文献   
130.
沙地生境不同播期对紫花苜蓿生产性能及其越冬率的影响   总被引:1,自引:0,他引:1  
为确定科尔沁沙地种植苜蓿(Medicago sativa)的适宜播期,本研究于2017年在内蒙古阿鲁科尔沁旗,选择骑士T、公农1号、擎天柱3个紫花苜蓿品种,7月1日开始播种,每5天播种1期,共10个播期,分析播期、生产性能、越冬率之间的关系。结果表明:建植当年苜蓿播种越晚干草产量越低,骑士T干草产量在7月21日播期显著降低(P<0.05),公农1号干草产量在7月16日播期显著降低(P<0.05),擎天柱干草产量在7月11日播期显著降低(P<0.05);随播种时期的推迟,苜蓿株高、单枝条重呈降低的变化趋势,单位面积株数和枝条数呈先增加后降低的变化趋势;苜蓿越冬率从播期7月16日开始显著降低,公农1号在7月16日以前播种越冬率显著高于骑士T和擎天柱(P<0.05);播种翌年第1茬苜蓿干草产量和株高随着播期的推迟而逐渐降低,2,3茬则无明显变化;苜蓿单位面积株数和枝条数都随播期的推迟呈降低的变化趋势,随着刈割茬次的增加,苜蓿的株数逐渐降低。因此,在科尔沁沙地种植紫花苜蓿最佳播期为7月1日—7月16日。  相似文献   
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