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51.
Shiilegdamba E Carpenter TE Perez AM Thurmond MC 《Veterinary research communications》2008,32(3):201-207
Prior to 2000, foot-and-mouth disease (FMD) had not been observed in Mongolia since 1973; however, between April 2000 and
July 2002, Mongolia reported 44 FMD outbreaks that affected cattle, sheep, goats, and camels. The objectives of this study
were to describe the distributions of the 44 reported FMD outbreaks in Mongolia and to assess their spatial clustering and
directions of movement. Official reports were collected to obtain the number and species of animals both affected and at risk,
and the date and geographical coordinates of each outbreak. Significant global and local spatial clusters of reported FMD
outbreaks were identified. Disease spread during the second epidemic moved 76° northeast and the spread of the disease during
the third epidemic moved 110° northwest. FMD outbreaks were clustered intensely close to other FMD-positive counties. These
findings can be used in the future to help plan prevention and control measures in high risk areas. 相似文献
52.
53.
Silvia Pietschmann Katrin Hoffmann Michael Voget Ulrich Pison 《Veterinary research communications》2009,33(6):489-505
The therapeutic value of antibiotics depends on the susceptibility of the infecting microorganism and the pharmacological
profile of the drugs. To assess the value of an antibiotic combination of polymyxin B and miconazole this study examined the
in vitro synergistic potential of the two drugs on Gram-negative and Gram-positive bacteria and yeast. Antifungal and antibacterial
activity was tested by minimum inhibitory concentration (MIC) of broth macrodilution and urea broth microdilution, by fluorescence
microscopy and flow cytometry. Synergism was calculated using the fractional inhibitory concentration index (FICi). With Staphylococcus intermedius as target we found up to an eightfold reduction of the individual MICs when both drugs were combined. However, the FICi was
0.63 suggesting no real interaction between the two drugs. With Escherichia coli, Pseudomonas aeruginosa, and Malassezia pachydermatis as targets the antimicrobial drug combination reduced the MICs of polymyxin B and miconazole from fourfold to hundredfold
resulting in FICi between 0.06 and 0.5 which defines a synergistic action. Thus, if polymyxin B and miconazole are combined
their effect is greater than the sum of the effects observed with polymyxin B and miconazole independently, revealing bactericidal
and fungicidal synergism. Our results indicate a strong therapeutic value for the combination of these antimicrobial agents
against Gram-negative bacteria and yeast and a weaker value against Gram positive bacteria for clinical situations where these
pathogens are involved. 相似文献
54.
Danilo T. Stipp Aline F. Barry Alice F. Alfieri Elisabete Takiuchi Alexandre M. Amude Amauri A. Alfieri 《Tropical animal health and production》2009,41(7):1563-1567
Bovine coronavirus (BCoV) is one of the main causes of neonatal calf diarrhoea. Several diagnostic assays have been employed
to detect the presence of the virus in stool samples from calves. Despite this, the frequency of BCoV infection among Brazilian
and even South American cattle herds has yet to be well characterised. This study describes the occurrence of BCoV infection
among calves from dairy and beef herds in four Brazilian states. A total of 282 stool samples from 1 to 60-day-old calves
were evaluated for the presence of BCoV by a semi-nested (SN) PCR assay. The animals were from herds (n = 23) located in three geographical regions in Brazil (south, southeast, and center-west). The specific BCoV amplicon was
detected in 15.6% (44/282) of the faecal specimens examined, of which 95.4% (42/44) were from diarrhoeic and 4.6% (2/44) from
asymptomatic calves. The specificity of the SN-PCR amplicons was evaluated by restriction fragment length polymorphism (RFLP)
analysis. The results show that the BCoV is widespread, mainly among calves from 16 to 30-days-old (p = 0.0023), and verify the association between BCoV infection and clinical signs of diarrhoea (p = 0.005). These findings emphasise the importance of this virus in enteric infections of Brazilian cattle herds. 相似文献
55.
Denis M Lacy-Hulbert SJ Buddle BM Williamson JH Wedlock DN 《Veterinary research communications》2011,35(3):145-156
The presence, phenotype and function of Streptococcus uberis-specific T cells in the mammary gland secretion (MGS) and blood of cows exposed to S. uberis were assessed. MGS T cells in the udder were purified and incubated with autologous blood monocytes as antigen-presenting
cells (APC). Most cows, irrespective of prior S. uberis infection status and lactation status, were shown to have S. uberis-specific T cells both in MGS and in the blood. When cells from a subgroup of cows were studied, it was found that the S. uberis-specific T cells produced high levels of interferon-gamma (IFN-γ), but low levels of interleukin-10 (IL-10). A high percentage
of responding T cells were of the CD8
+
memory (CD45RO) subset. T cells from the MGS specific for S. uberis were propagated from animals during the drying off period and expanded in vitro using interleukin-2 (IL-2) and S. uberis antigens. This led to the accumulation of T cells of the CD8
+
subset bearing memory cell markers (CD45A
−
, CD45RO
+
), which released high levels of IFN-γ. Four of the five T cell lines derived from the MGS of three animals had substantial
direct killing activity towards S. uberis in vitro. It is concluded that there is an emergence of S. uberis-specific bactericidal T cells in the MGS of cows after infection or environmental exposure to S. uberis. Vaccines aimed at activating and expanding this T cell population in the mammary glands of cattle may offer an avenue for
the prevention of mastitis caused by S. uberis. 相似文献
56.
Ouédraogo-Koné S Kaboré-Zoungrana CY Ledin I 《Tropical animal health and production》2008,40(2):155-164
Foliage of Afzelia africana, Pterocarpus erinaceus and Khaya senegalensis, from 10 trees per species, was collected every two weeks during the late dry, rainy and cool season to determine the seasonal
effects on chemical composition. Fifteen rams of the Djallonké breed, weighing on average 20.0 kg, were used to evaluate the
voluntary intake and digestibility of hay of A. gayanus, foliage of A. africana (as a sole feed), and A. africana, P. erinaceus and K. senegalensis offered with 30% of the diet as A. gayanus hay. The crude protein (CP) content of A. africana, and P. erinaceus decreased significantly from the late dry season to the cool season when that of K. senegalensis tended to increase. The mean CP of A. africana, P. erinaceus and K. senegalensis differed significantly (173 g, 139 g and 114 g/kg DM, respectively). The DM intake of A. africana offered with hay (571 g/d) or as a sole feed (598 g/d) were not significantly different, but was higher than that of P. erinaceus (428 g/d) and K. senegalensis (298 g/d). The digestibility calculated by difference of DM and CP of A. africana (582 g/kg DM and 795 g/kg CP, respectively) did not differ significantly from A. africana as a sole feed, but were higher than for the other species. The nutritive value of A. africana seems to justify the high preference of herders for this species. 相似文献
57.
A cross-sectional survey was conducted in Sudan to determine sero-prevalence and risk factors associated with Neospora caninum infection in non-vaccinated dairy herds and to assess importance of the disease. Blood samples were collected from a total
of 262 animals from 25 herds. Sera were tested for antibodies against N. caninum using ELISA test. The prevalence rates of N. caninum antibodies in cattle were high both at herd level (44%) and at individual animal level (10.7%). Herd level infection rates
were similar in Khartoum State (43.7%) and at Gazira States (44.4%). The overall prevalence rates were higher (16.1%) in Gazira
State than in Khartoum State (9%) but with no significant variation. The sero-prevalence at individual animal level was significantly
higher (p < 0.05) in animals with history of abortion (12.8%) than in apparently healthy animal (11.3%), animal with history of infertility
(8.1%), or neonatal death of calves (4.3%). In addition, significantly higher (P < 0.05) sero-prevalence was observed in samples collected during the rainy season (6.87%) than winter (3.05%) or summer (0.76%).
However, no significant differences in sero-prevalence due to locality, animal breed, sex, and age were observed (p > 0.05). This preliminary study reveals for the first time the existence of natural N. caninum infection in Sudan. Also, the findings of the present study indicated that this disease is highly prevalent in two major
areas of dairy production in the country, and this calls for control strategy to be implemented. 相似文献
58.
Probiotics of Lactobacillus acidophilus, Saccharomyces cerevisiae, and Aspergillus niger and three commercial exogenous fibrolytic enzymes (EFE) were tested in vitro to select best source and optimum dose followed
by in vivo studies on male buffalo calves. Bacterial (P < 0.001) and protozoal population were increased significantly (P < 0.001) with probiotics and EFE. In vitro dry matter digestibility was more (P < 0.001) on L. acidophilus and then on S. cerevisiae. Dose required for L. acidophilus and S. cerevisiae probiotics was 1 × 109 and 3 × 109 cfu/flask, respectively. Cellulase and xylanase were effective at 4,000 and 12,500 IU/kg DM. In vitro cell wall digestibility
was increased (P < 0.001) when probiotics and EFE were used together. Best source and optimum dose of probiotics and EFE were fed to 18 male
buffalo calves with concentrate supplement (CS). Calves were randomly divided into three groups either without probiotics
and EFE (CG) or with probiotics (EG1) or probiotics combined with EFE (EG2) on wheat straw diet. Organic matter, neutral detergent fiber, and acid detergent fiber digestibility was improved significantly.
Average daily weight gain (ADG) and feed efficiency were significantly higher (P < 0.001) in EG2 than EG1 or CG. Final body weight was 4% and 12% and feed efficiency was 2.6% or 1.6% more (P < 0.001) in EG2 compared to CG or EG1, respectively. Fortification of CS with probiotics and EFE together had more impact on FE and ADG in buffalo calves. 相似文献
59.
K Ashley S Wilson JR Young HP Chan S Vitou S Suon PA Windsor RD Bush 《Tropical animal health and production》2018,50(1):63-73
Forage technology has been successfully introduced into smallholder cattle systems in Cambodia as an alternative feed source to the traditional rice straw and native pastures, improving animal nutrition and reducing labour requirements of feeding cattle. Previous research has highlighted the positive impacts of forage technology including improved growth rates of cattle and household time savings. However, further research is required to understand the drivers, challenges and opportunities of forage technology for smallholder cattle households in Cambodia to facilitate widespread adoption and identify areas for further improvement. A survey of forage-growing households (n = 40) in July–September 2016 examined forage technology adoption experiences, including reasons for forage establishment, use of inputs and labour requirements of forage plot maintenance and use of forages (feeding, fattening, sale of grass or seedlings and silage). Time savings was reported as the main driver of forage adoption with household members spending approximately 1 h per day maintaining forages and feeding it to cattle. Water availability was reported as the main challenge to this activity. A small number of households also reported lack of labour, lack of fencing, competition from natural grasses, cost of irrigation and lack of experience as challenges to forage growing. Cattle fattening and sale of cut forage grass and seedlings was not found to be a widespread activity by interviewed households, with 25 and 10% of households reporting use of forages for these activities, respectively. Currently, opportunities exist for these households to better utilise forages through expansion of forage plots and cattle activities, although assistance is required to support these households in addressing current constraints, particularly availability of water, if the sustainability of this feed technology for smallholder cattle household is to be established in Cambodia. 相似文献
60.