首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   14篇
  免费   1篇
林业   1篇
农学   2篇
  1篇
综合类   2篇
水产渔业   1篇
畜牧兽医   6篇
植物保护   2篇
  2023年   1篇
  2020年   2篇
  2018年   2篇
  2016年   1篇
  2015年   1篇
  2014年   1篇
  2013年   2篇
  2011年   2篇
  2006年   1篇
  2004年   1篇
  1999年   1篇
排序方式: 共有15条查询结果,搜索用时 15 毫秒
1.

Using a cross-sectional survey, we determined the prevalence and risk factors associated with bovine brucellosis in herds under extensive production system in southwestern Nigeria. Antibodies to Brucella species in serum samples were tested using the Rose Bengal test (RBT) and competitive enzyme-linked immunosorbent assay (cELISA); for milk, the milk ring test (MRT) and indirect-ELISA (i-ELISA) were used. Questionnaire was administered to cattle herdsmen to determine factors predisposing the animals to bovine brucellosis. Data were analyzed using STATA 12. From 513 serum and 635 milk samples tested among 120 herds, overall animal-level prevalence of 10.1% (95% CI 7.5–12.7%) and 20.2% (95% CI 17.1–23.3%) were recorded by RBT and MRT, respectively; while 9.4% (95% CI 6.9–11.9%) and 17.8% (95% CI 14.8–20.8%) were obtained using cELISA and i-ELISA, respectively. In all, from the 120 herds tested, 29.2% and 43.3% were positive by RBT and MRT, respectively. Multivariable logistic regression revealed that herd location (OR?=?8.12, 95% CI 1.68–38.90) and improper disposal of placenta/fetus (OR?=?17.33, 95% CI 4.81–62.33) were predictors for a seropositive herd using RBT; while herd location (OR?=?5.13, 95% CI 1.27–20.28), large herd size (OR?=?2.62, 95% CI 1.15–5.85), and occurrence of abortion for a year or more (OR?=?4.62, 95% CI 1.53–13.71) were predictors of seropositivity to antibodies to Brucella spp. using MRT. We found high prevalence of brucellosis in cattle herds under extensive management system in southwestern Nigeria. Urgent and coordinated control strategies are required to mitigate this problem.

  相似文献   
2.
The haematological effect of ethanolic extract of Allium ascalonicum was evaluated in male albino rats during a 21 day administration at the doses of 50, 100 and 200 mg/kg b.w, orally. Parameters evaluated include the serum lipids, red and white cell indices. The results showed that the extract administered decreased most of the parameters relating to red cell and increased most of those parameters relating to white cells. It also decreased the total cholesterol (TCH), high density lipoprotein cholesterol (HDL) and low density lipoprotein cholesterol (LDL) with no significant effect on the triglyceride levels.  相似文献   
3.
Monitoring the physical, chemical and biological properties during accelerated composting enables concise determination of its stability and maturity. Determination of physical parameters such as pH, moisture and temperature, chemical parameters such as total nitrogen (N), phosphorus (P), potassium (K), organic matter and humic acid as well as biological parameters such as microbial count and carbon dioxide (CO2) evolution was carried out during a four (4) week composting period, The trend observed for pH showed the mesophilic and thermophilic phases and a similar trend was observed for the compost temperature. Intermittent increase and decrease was observed for total N, P, K as well as for the fungal and bacterial population. A direct relationship was observed among the bacterial population, CO2 evolution and humic acid. However, composting for four (4) weeks produced a stable compost, which was evident through the physical observation of the final product and the results obtained for the chemical and biological parameters.  相似文献   
4.
5.

A thorough knowledge of cattle herding systems is very important for planning sustainable genetic improvement and conservation strategies. This paper is initiated to characterize Benin native Borgou cattle farming systems in its department of origin by mean of survey including 180 cattle farmers owning at least one phenotype of that breed. Using multiple correspondence analysis and hierarchical ascending classification, four groups of Borgou cattle farms have been identified. The first group qualified as “semi-intensive purebred Borgou cattle farming” own high numbers (87.2 ± 3.95 heads) purchased and reared with the view to promote its genetic improvement, its production, and its conservation as Benin animal genetic resource. The second group (sedentary purebred Borgou cattle farming) is represented by Bariba ethnic group with small numbers (22.18 ± 0.71 heads) of purebred Borgou cattle used mainly for draught. Cattle farmers of the third group are “large transhumant of Zebu and Borgou crossbred cattle farmers” represented by Fulani and Gando ethnic groups whose herds are generally composed of high numbers (75.20 ± 3.43 heads) of cattle acquired by purchasing, inheriting, and fostering. The last one is the “small transhumant of Zebu and Borgou crossbred cattle farming” with an average herd size of 31.98 ± 0.72 heads. Cattle farming is their main activity and animals are used for the production of milk and cheese. These distinctions between Borgou cattle farmers can be an anchorage point for designing sustainable community-based in situ conservation strategies for safeguarding this local breed in its original cradle.

  相似文献   
6.
Two experiments were carried out to determine the effects of diets containing fermented and amino acid (AA)-supplemented malted sorghum sprout (MSP) on performance, nutrient utilisation and feed cost analysis of growing pigs. In experiment 1 (digestibility trial), 12 pigs were individually housed in metabolic crates, equipped with feeding and watering troughs which also allow for separate collection of faeces and urine. Data collection lasted for 7 days during which feed intake and faecal output were weighed, with daily storage of collected faeces at ?4 °C. Four diets, a basal diet, basal plus malted sorghum sprout (B?+?MSP), basal plus fermented malted sorghum sprout (B?+?FMSP) and basal plus amino acids plus malted sorghum sprout (B?+?AA?+?MSP), were tested. Samples of test ingredients, feed and faeces were analysed for their gross energy and proximate compositions. In experiment 2, 18 weaner pigs were used in a completely randomised design for 63 days to determine the performance and cost analysis of feeding malted sorghum sprout at 0, 100 and 200 g/kg in pig’s diet, six pigs per diet with each pig representing a replicate. Daily feed intake and weekly weight gain were determined. The prevailing cost of each feed ingredient was used to compute the feed cost and, subsequently, the feed cost analysis. Results of digestibility trial showed that there was no difference in the utilisation of the chemical constituents of B?+?MSP and B?+?AA?+?MSP diets, which were also similar to the basal diet, except the crude protein (CP) in amino acid-supplemented malted sorghum sprout diet, which was lower compared to the basal diet. B?+?FMSP was lower (P?<?0.05) in the digestibility of dry matter, organic matter and CP compared to the basal diet. The digestible energy (DE) and the fraction of gross energy utilised as DE of each diet also were not affected by fermentation and supplementation with AA. In experiment 2, the levels of MSP used did not affect (P?>?0.05) the performance and feed cost indices measured. It was concluded that MSP can be used in growing pig’s diet, without the need for fermentation and AA supplementation, at 200 g/kg level with no adverse effect on the nutritive value of the diet.  相似文献   
7.
We report the development of a novel and more efficient, rapid, cost-effective and simple technique than current PCR-based identification methods for screening cotton (Gossypium hirsutum) plants for the presence of cotton leafroll dwarf virus (CLRDV). This protocol takes advantage of the PACE (PCR Allele Competitive Extension) system and uses PCR amplification of cDNA, coupled with sequence-specific fluorescent probes to differentiate between infected and uninfected cotton plants. This procedure has the potential for application in detection of other RNA viruses in a variety of other crops, by using primers specific for the RNA-dependent RNA polymerase (RdRP) gene and a widely conserved housekeeping gene in the host organism; in this case, the G. hirsutum polyubiquitin gene (GhUB).  相似文献   
8.

This study aimed at determining chicken genotypes of choice and traits preference in chicken by smallholder farmers in Nigeria. Data were obtained from a total of 2063 farmers using structured questionnaires in five agro-ecological zones in Nigeria. Chi square (χ2) statistics was used to explore relationships between categorical variables. The mean ranks of the six genotypes and twelve traits of preference were compared using the non-parametric Kruskal–Wallis H (with Mann–Whitney U test for post hoc separation of mean ranks), Friedman, and Wilcoxon signed-rank (with Bonferroni’s adjustments) tests. Categorical principal component analysis (CATPCA) was used to assign farmers into groups. Gender distribution of farmers was found to be statistically significant (χ2?=?16.599; P?≤?0.002) across the zones. With the exception of Shika Brown, preferences for chicken genotypes were significantly (P?≤?0.01) influenced by agro-ecological zone. However, gender differentiated response was only significant (P?≤?0.01) in Sasso chicken with more preference by male farmers. Overall, FUNAAB Alpha, Sasso, and Noiler chicken were ranked 1st, followed by Kuroiler (4th), Shika Brown (5th), and Fulani birds (6th), respectively. Within genotypes, within and across zones and gender, preferences for traits varied significantly (P?≤?0.005 and P?≤?0.01). Traits of preference for selection of chicken breeding stock tended towards body size, egg number, egg size, and meat taste. Spearman’s rank order correlation coefficients of traits of preference were significant (P?≤?0.01) and ranged from 0.22 to 0.90. The two PCs extracted, which explained 65.3% of the variability in the dataset, were able to assign the farmers into two groups based on preference for body size of cock and hen and the other ten traits combined. The present findings may guide the choice of appropriate chicken genotypes while the traits of economic importance may be incorporated into future genetic improvement and conservation programs in Nigeria.

  相似文献   
9.
Intact microencapsulated protozoeal diets (MED), added to 5 m filtered hatchery water at the recommended concentration of 4 mg L-1 gave no significant difference in bacterial numbers after 6 h, over a 48 h period compared to control groups in autoclaved hatchery water. Disruption of the MED resulted in a significant increase in bacterial numbers up to 12 h compared to controls with intact microcapsules. Protein leach rates were similar in sterile water and 5 m filtered water, indicating that leaching was independent of microbial activity. MED leached significantly less dietary solubles compared to a microparticulate diet (MPD). There was no evidence to suggest significant attachment of bacteria to diet particles for at least 48 h.In low-quality water after algal blooms, survival of white shrimp (Penaeus indicus) larvae was poor when reared in both sterile and 5 m filtered water. The addition of bacteria filtered from xenic algal cultures together with the algal exudates to such water gave significant improvements in survival to larvae fed MED in 5 m filtered water but not in autoclaved culture water. Live algal diets promote high larval survival and growth irrespective of the inclusion of bacteria.It is suggested that algal exudates act as selective bacteriocides and total replacement of algae with MED requires a balanced bacterial community which can be attained at times from natural sea water, or when the natural bacterial community balance is disturbed, corrected by the use of algal exudates.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号