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31.
32.
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
33.
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
34.
Khanyisile Mdladla Edgar Farai Dzomba Farai Catherine Muchadeyi 《Tropical animal health and production》2017,49(3):515-527
Expansion of goat improvement programs requires exploration of the factors that influence the production system and breeding initiatives. Characterization of goat breeds or populations is crucial in providing information on prevalent goat types and their attributes and may suffice as a guideline on conservation, development, and selection for improved productivity. This study investigated the existing village goat production system and phenotypic diversity of the different village populations from four South African provinces. The study further investigated the use of phenotypic attributes to classify goats to breeds or populations. Data was collected from 142 households in 26 villages of the Eastern Cape (n?=?2 villages), KwaZulu-Natal (n?=?6 villages), Limpopo (n?=?13 villages), and North West (n?=?5 villages) provinces through a survey. Individual interviews and focus group discussions revealed that the mean goat herd size per household was least in Limpopo at 13.2?±?12.40 and highest in Eastern Cape (34.18?±?28.36). Flocks had more (p?<?0.05) adults than kids, and the distribution of breeding animals was biased towards does and less bucks. Goats were kept mainly for meat, for selling, and for ritual ceremonies. The goat production system was mainly scavenging. Goat health was a major challenge across households and villages. Qualitative traits such coat, horn, ears, and wattle characteristics were recorded for populations of village goats (n?=?319) and a feral Tankwa breed (n?=?50). The dominant coat pattern was plain (74.53%) with black as the most common coat color (31.98%). Across breeds, a majority (88.08%) of the goats had horns, and 7.59% had wattles while 56.64% had beard. Adult goats (<3 years; n?=?398) were further analyzed for five quantitative traits of chest girth, height, length, and pin bone and there were significant (p?<?0.05) breed differences in all. A stepwise discriminatory procedure was used to rank the quantitative traits according to their discriminatory power to separate breeds or populations. Significant traits were then subjected to canonical discriminant analysis for principle component analysis. Based on the quantitative traits, the Tankwa, Xhosa, and Tswana goats formed their own cluster separated from commercial meat type breeds and the Venda and Zulu ecotypes. The discriminant function analysis correctly classified 90.41% of the Zulu goats and 82.93% of the Xhosa village populations. None of the Savanna goats were correctly classified. The study demonstrated diversity in village goat populations and production systems, which would allow for within population selection in genetic improvement programs. The heterogeneity in the phenotypic traits in the village goats is reflective of the role of village production systems in the maintenance of animal diversity in local populations. 相似文献
35.
Awareness of animal influenza and its prevention and control is important for ensuring livestock health, production and welfare. In China, a country stereotyped as a major source of emerging zoonotic infectious diseases, research on the public understanding of animal influenza is limited to the Han, the main ethnic group. The present qualitative study in Southwest China investigated awareness of animal influenza among the Dai, an ethnic minority. The participants (15 men and 10 women, ages 18–83) were smallholder farmers of pigs and poultry in rural areas of Jinghong, Xishuangbanna, Yunnan Province. A mixture of interviews and group discussions took place in homes and villages. The participants were asked about their knowledge of avian influenza (H7N9), swine influenza (H1N1), precautions taken to protect against influenza, procedures when animals were sick and perceived risk of animal influenza. The data were analysed following coding and thematic analysis. The findings demonstrated a limited understanding of animal health and welfare among participants. Specifically, they were largely unaware of animal influenza (H7N9, H1N1) including its causes, symptoms, prevention and treatment. The farmers were also uninformed of the risks they faced and unknowingly engaged in behaviours which increased direct or indirect exposure to infected animals, a risk factor for human infection. They also reported poor usage of veterinary services. In order to guarantee the health, welfare and production of their livestock, immediate action is needed to enable Dai smallholder farmers to prevent and respond to animal influenza effectively and timely. 相似文献
36.
Ezenduka EV Oboegbulem SI Nwanta JA Onunkwo JI 《Tropical animal health and production》2011,43(3):557-559
The use of antimicrobial agents in poultry production results in their accumulation in the body tissues and products such
as milk and egg. The subsequent accumulation of these drugs and their metabolites in body cells is known as drug residue.
This study was designed to determine the prevalence of antimicrobial residues in eggs from poultry farms and retail outlets
in Enugu State, Nigeria. Eggs from 25 selected commercial farms and ten retail outlets were screened for the prevalence of
antimicrobial residue. Also, structured questionnaires were administered to 25 commercial farms in the state to determine
the management practices and the most widely used antimicrobial drugs in farms and possible association between the management
practices and the occurrence of antimicrobial residues in eggs from these farms. All the 25 farms surveyed use oxytetracycline.
Eggs from nine of the surveyed farms tested positive for antimicrobial residue and three of the ten surveyed farms also tested
positive for antimicrobial residue. No association was observed (p 0.05; Fisher’s exact test) between the occurrence of antibiotic residues in eggs and farm size, feed source and housing systems.
This study was able to demonstrate the presence of antimicrobial residues in eggs destined for human consumption. Drugs like
nitrofurans which has been banned for use in food animals are still very much in use in Enugu State, Nigeria. Antibiotics
given as feed additives may give rise to drug residues in food animals. 相似文献
37.
38.
39.
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
40.
Michael H. Woodford 《Tropical animal health and production》2009,41(7):1023-1033
Proliferation of disease pathogens capable of affecting humans, domestic livestock and wildlife increasingly threatens environmental
security and biodiversity. Livestock and wild animals in proximity to human beings are often in the chain of transmission
and infection. Globalization of industrial livestock production (especially poultry upon which so much of the burgeoning human
population depends) often permits transcontinental disease spread. Rapidly expanding (and often illegal) international trade
in wild and domestic animals and their products are increasingly involved in the emergence of new diseases that may have the
ability to transmit among humans, livestock and wildlife. Rapidly increasing urbanization has led in many places to overcrowded
townships that rely on “bushmeat” for sustenance and has contributed to the emergence of virulent zoonotic pathogens. The
emergence and proliferation of pathogens are exacerbated by anthropogenic transformation of natural landscapes in order to
increase agricultural and livestock production. This paper posits that data gathered by veterinary ecologists should be interpreted
and used by other disciplines. The importance of a thorough knowledge of the “natural history” (ecology) of the disease agent
and its human, domestic and wild hosts is stressed. 相似文献