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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.

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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   
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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   
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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.

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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   
8.
Synchronization of the donor cell cycle is an important factor for successful animal cloning by nuclear transfer. To improve the efficiency of porcine cloning, in the present report, we evaluated effects of contact inhibition, serum starvation and roscovitine treatment of donor cells on in vitro and in vivo developmental potency of cloned porcine embryos. Fibroblasts derived from a porcine foetus at day 30 of gestation were isolated and cultured to 70% confluency. Then, cells were either cultured to 100% confluency for contact inhibition, or cultured in 0.5% serum for 72 h for serum starvation or with 15 μm roscovitine for 24 h. Cells were most effectively synchronized at G0/G1 in the serum starvation group (87.5%) compared with the contact inhibition and roscovitine treatment groups (76.3% and 79.9% respectively p < 0.05). However, after somatic cell nuclear transfer followed by in vitro culture, the serum starvation group showed a significantly lower blastocyst formation rate (5.6%) compared with the contact inhibition and roscovitine treatment groups (11.6% and 20.0% respectively). Differential expression of apoptosis‐related genes and the level of apoptosis in each treatment group explain the variation in developmental competence among the groups. Significantly higher level of apoptosis was observed in the serum starvation group. On the other hand, the roscovitine treatment group shows the lowest level of apoptosis and the best in vitro development among the groups. Cloned embryos derived from roscovitine‐treated donor cells were transferred to surrogate pigs. Three healthy live piglets were produced. In conclusion, we suggest that roscovitine treatment of donor cells improves development of cloned porcine embryos and can raise the efficiency of cloned piglet production.  相似文献   
9.
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   
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