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1.
The digestive tract of termite(Microcerotermes diversus) contains a variety of lignocellulose-degrading bacteria with exocellulases enzyme activity, not found in the rumen, which could potentially improve fiber degradation in the rumen. The objectives of the current study were to determine the effect of inoculation of rumen fluid(RF) with three species of bacteria isolated from termite digestive tract, Bacillus licheniformis, Ochrobactrum intermedium, and Microbacterium paludicola, on in vitro gas production(IVGP), fermentation parameters, nutrient disappearance, microbial populations, and hydrolytic enzyme activities with fibrous wheat straw(WS) and date leaf(DL) as incubation substrate. Inoculation of RF with either of three termite bacteria increased(P0.05) ammonia-N concentration compared with the control group(free of termite gut bacteria). Termite bacteria inoculation had no effect(P0.05) on gas production characteristics, dry matter, organic matter and neutral detergent fiber disappearance, pH, and concentration and composition of volatile fatty acids. Population of proteolytic bacteria and protozoa, but not cellulolytic bacteria, were increased(P0.05) when RF was inoculated with termite bacteria with both WS and DL substrates. Inoculation of RF with termite bacteria increased protease activity, while activities of carboxymethyl-cellulase, microcrystalline-cellulase, α-amylase and filter paper degrading activity remained unchanged(P0.05). Overall, the results of this study indicated that transferring lignocellulose-degrading bacteria, isolated from digestive tract of termite, to rumen liquid increased protozoa and proteolytic bacteria population and consequently increased protease activity and ammonia-N concentration in vitro, however, no effect on fermentation and fiber degradation parameters were detected. These results suggest that the termite bacteria might be rapidly lysed by the rumen microbes before beneficial effects on the rumen fermentation process could occur.  相似文献   
2.
SUMMARY Effects of storage at room temperature (23–25°C) and refrigeration (4–5°C) on various biochemical constituents of camel serum were investigated. Albumin, globulin, calcium, phosphorus, cholesterol, aspartate aminotransferase (AST), alkaline phosphatase (AP) and gamma glutamyltransferase (GGT) did not change over 9 days when stored at 4–5°C. At 4–5°C, creatinine, iron and glucose in camel sera remained stable for 6 days; total protein for 7 days; and blood urea nitrogen for 8 days. Decreased activities in creatine kinase (CK), lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) were apparent after 1, 6 and 7 days, respectively. At room temperature, total protein, albumin, globulin, calcium and phosphorus were stable throughout the 9 days. Changes in glucose and iron occurred after 3 days. Stability at room temperature for LDH was 1 day; AST, 3 days; GGT and ALT, 6 days; and AP, 8 days. CK activity had already declined by 4 hours and by 9 days, only 34% activity remained.  相似文献   
3.
耕作方式对岩溶区甘蔗地土壤优先流特征的影响   总被引:2,自引:0,他引:2  
陈晓冰  严磊  李振东  SAEED R  陈廷速  甘磊 《土壤》2019,51(4):786-794
岩溶区特殊的岩性地质条件,使土壤优先流现象广泛发生。以广西岩溶区内的典型农地甘蔗地作为研究对象,利用野外染色示踪技术和图像解析方法,分别对传统耕作(CT)和粉垄耕作(SRT)方式下的田间土壤优先流特征进行分析,揭示耕作方式对岩溶区甘蔗地土壤优先流的发生及其空间发展变化的影响。结果表明:①在相同外部供水条件下,传统耕作甘蔗地优先流运动分化程度相对较高,多呈指状形式,且平均湿润锋下渗深度为43.19 cm,显著大于粉垄耕作(P0.05),而粉垄耕作甘蔗地优先流以横向运动形式为主,表现为团块状湿润锋形式;②粉垄耕作甘蔗地土壤优先流发生时间显著滞后于传统耕作(P0.05),是其1.67倍;③随土壤深度的增加,两种耕作方式下的甘蔗地土壤优先流发育程度总体呈现先增加后降低的变化趋势,但粉垄耕作甘蔗地优先流比(70.72%)和长度指数(527.12%)均显著小于传统耕作甘蔗地(P0.05),且在土壤空间中对应的染色形态变异系数(1.19)是传统耕作的1.38倍,优先流发育程度显著低于传统耕作甘蔗地。粉垄耕作与传统耕作方式相比,在一定程度上降低了田间土壤优先流现象,改善了田间土层中的水肥状况。  相似文献   
4.
Objective— To describe a minimally invasive technique for preparation of teaser rams by needle-assisted ligation through the tail of the epididymis.
Study Design— Experimental study.
Animals— Mature rams (n=6), estrus-induced ewes (2).
Methods— After local anesthesia, epididymis ligation was achieved by restraining the testis distally within the scrotal sac and passing suture through a hypodermic needle inserted between tail of epididymis and distal pole of testis, caudomedial to craniolateral through the scrotum. The needle was removed leaving the suture in place and the testis pushed up dorsally, then the needle was reinserted through the original holes and the suture passed back through the needle, which was withdrawn. This resulted in the suture forming a complete loop around the epididymis. The suture ends were tied ligating the epididymis. Semen was evaluated pre- and postligation. Testes were removed after 30 days for gross and histologic examination.
Results— Epididymis ligation was accomplished without postoperative complications. Three weeks after the epididymis ligation, no motile and live spermatozoa were found in ejaculates. From 5 to 28 days after epididymis ligation, attraction to ewes and libido was unchanged and similar to 14 days before ligation.
Conclusions— This novel minimally invasive technique is a simple, alternative method for preparation of teaser rams.
Clinical Relevance— This method is simply performed, without skin wounds, and minimal postoperative care is needed. The technique should be readily adaptable to other species.  相似文献   
5.
西南岩溶区粉垄耕作和免耕方式下甘蔗地土壤优先流特征   总被引:2,自引:2,他引:2  
以西南岩溶区的典型农地甘蔗地为研究对象,采用野外染色示踪技术,利用形态学解析手段,并结合土壤水分分层评价方法,对粉垄耕作和免耕方式下甘蔗地土壤优先流特征进行研究。结果表明:在相同外部供水条件下,粉垄耕作甘蔗地水分下渗湿润锋迹线较免耕甘蔗地平缓,呈均匀整体形式下渗,平均下渗深度是免耕甘蔗地的0.95倍,其优先流染色形态相对于免耕甘蔗地的枝状分化状态,多以零散团块状分化形式为主;在相同外部条件下,免耕甘蔗地最先发生优先流现象,优先流的发生速度是粉垄耕作甘蔗地的1.45倍,平均优先流比达88.61%,大于粉垄耕作甘蔗地(82.89%),二者之间差异显著(P0.05);沿土壤深度的增加,优先流在粉垄耕作甘蔗地土壤空间中的发展变化程度表现为"次活跃—活跃—次活跃—相对稳定—次活跃",而免耕甘蔗地表现为"次活跃—活跃—次活跃—相对稳定",免耕甘蔗地的优先流空间发展变化程度较高,主要发生在5—35cm土层范围内,相比粉垄耕作甘蔗地10—30cm土层深。粉垄耕作方式与免耕方式相比,降低了岩溶区甘蔗地土壤优先流的发生与发展,在一定程度上提高了土壤的保肥蓄水能力。  相似文献   
6.
Abstract. Bacterial agglutination, passive haemagglutination, complement-dependent passive haemolysis, indirect immunofluorescence, agar gel immunodiffusion and agglutination with fractions of immunized fish serum were compared for detecting humoral antibody to the lipopolysacchande (LPS) of Edwardsiella icialuri Hawke in channel catfish. Bacterial agglutination titres averaged 1: 672; passive haemagglutination titres averaged 1: 1152; and complement-dependent haemolysis titres averaged 1: 2360. Serum from non-vaccinated fish ranged from 0 to 1:32. Indirect fluorescence and immunodiffusion demonstrated positive reactions to the LPS antibody. Fractionation of immune sera produced three fractions, one of which strongly haemagglutinated E. ictaluri but the other two did not. All six serological techniques were sensitive to E. ictaluri LPS antibody.  相似文献   
7.
Estimation of above-ground biomass is vital for understanding ecological processes. Since direct measurement of above-ground biomass is destructive, time consuming and labor intensive, canopy cover can be considered as a predictor if a significant correlation between the two variables exists. In this study, relationship between canopy cover and above-ground biomass was investigated by a general linear regression model. To do so, canopy cover and above-ground biomass were measured at 5 sub-life forms(defined as life forms grouped in the same height classes) using 380 quadrats, which is systematic-randomly laid out along a 10-km transect, during four sampling periods(May, June, August, and September) in an arid rangeland of Marjan, Iran. To reveal whether obtained canopy cover and above-ground biomass of different sampling periods can be lumped together or not, we applied a general linear model(GLM). In this model, above-ground biomass was considered as a dependent or response variable, canopy cover as an independent covariate or predictor factor and sub-life forms as well as sampling periods as fixed factors. Moreover, we compared the estimated above-ground biomass derived from remotely sensed images of Landsat-8 using NDVI(normalized difference vegetation index), after finding the best regression line between predictor(measured canopy cover in the field) and response variable(above-ground biomass) to test the robustness of the induced model. Results show that above-ground biomass(response variable) of all vegetative forms and periods can be accurately predicted by canopy cover(predictor), although sub-life forms and sampling periods significantly affect the results. The best regression fit was found for short forbs in September and shrubs in May, June and August with R~2 values of 0.96, 0.93 and 0.91, respectively, whilst the least significant was found for short grasses in June, tall grasses in August and tall forbs in June with R~2 values of 0.71, 0.73 and 0.75, respectively. Even though the estimated above-ground biomass by NDVI is also convincing(R~2=0.57), the canopy cover is a more reliable predictor of above-ground biomass due to the higher R~2 values(from 0.75 to 0.96). We conclude that canopy cover can be regarded as a reliable predictor of above-ground biomass if sub-life forms and sampling periods(during growing season) are taken into account. Since,(1) plant canopy cover is not distinguishable by remotely sensed images at the sub-life form level, especially in sparse vegetation of arid and semi-arid regions, and(2) remotely sensed-based prediction of above-ground biomass shows a less significant relationship(R~2=0.57) than that of canopy cover(R~2 ranging from 0.75 to 0.96), which suggests estimating of plant biomass by canopy cover instead of cut and weighting method is highly recommended. Furthermore, this fast, nondestructive and robust method that does not endanger rare species, gives a trustworthy prediction of above-ground biomass in arid rangelands.  相似文献   
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10.
Objective— To determine outcome and survival rate after surgical treatment of intestinal atresia, gender predilection, and effect of rectal palpation on the cause of atresia coli in calves.
Study Design— Prospective clinical study.
Animals— Newborn calves (n=68).
Methods— Data collected were husbandry system, anamneses, physical examination findings, surgical treatments, and postoperative results. Calves with atresia ani, and with atresia coli et recti had anal reconstruction and right flank colostomy, respectively. In midflank colostomized calves, the inner muscular layers were dissected to form a valve-like stoma.
Results— Of 68 calves with intestinal atresia, 37 were treated surgically. Anal reconstruction was performed in 21 calves with atresia ani with a long-term survival rate of at least 6 months with good condition. Colostomy was performed in 14 calves with atresia coli and 1 with atresia coli et recti; survival rate was 73%. The case morbidity rate for intestinal atresia was 13.8% and for atresia coli, 5.7% in the hospital population. No gender predilection for occurrence of atresia ani and atresia coli was identified. Palpation per rectum for early pregnancy diagnosis did not predispose to atresia coli.
Conclusion— Surgical treatment of atresia ani through circular anal skin removal has a good prognosis for survival. Colostomy is not an acceptable treatment from the calf's perspective because of the resulting poor condition but the high survival rate is important to allow continued milk production of the dam.
Clinical Relevance— Early diagnosis, supportive treatment, and surgical correction are important in management of atresia coli.  相似文献   
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