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81.
Lactose in normal saline was administered intravenously to a group of Zebu cattle infected with Trypanosoma vivax to determine the blood plasma kinetics at onset of an experimental infection and its ability to protect tissues against damage as part of preliminary studies to determine its suitability for use in the treatment of trypanosomosis. Significantly (P < 0.01) higher lactose concentrations were observed in the T. vivax-infected bulls at 30 min and 1 h (P < 0.05) post-infection (p.i.) and by 4 h p.i. the plasma lactose remained above the level prior to infusion, after which it fell slightly below the pre-infusion level in the uninfected group. Calculated pharmacokinetic parameters revealed delayed excretion of lactose in the T. vivax-infected group soon after infection. The total body clearance (Cl(B)) was significantly (P < 0.05) reduced. The biological half-life (t1/2), elimination rate constant (k(el)) and apparent volume of distribution (V(d)) were relatively decreased (P > 0.05) as a result of the T. vivax infection. Retention of lactose in the plasma was attributed to decreased plasma clearance. It is suggested that the presence of trypanosomes in circulation rather than organic lesions could have been responsible for the delay observed in the excretion of lactose. At 12 weeks p.i., when the experiment was terminated, the group infected and given lactose infusion (despite higher parasitaemia) had no gross or histopathological lesions in the brain, spleen, lymph nodes, heart, kidneys, liver and testes. However, the group infected but not infused with lactose were emaciated, had pale mucosae, watery blood, general muscular atrophy, serous atrophy of coronary fat and other adipose tissue, hepatomegaly, splenomegaly, swollen and oedematous lymph nodes, all of which are suggestive of trypanosomosis. Histopathological lesions included narrowing of Bowman's space and hypercellularity of glomerular tufts in the kidneys with the mean glomerular tuft nuclear indices (GTNs) in the group significantly higher (P < 0.01) than the mean GTNs of the lactose-infused and control bulls. Degenerative changes occurred in the myocardium, spleen, testes and epididymides. The tesicular and epididymal lesions are indicative of male reproductive dysfunction.  相似文献   
82.
Tropical Animal Health and Production - In comparison with other livestock, tuberculosis (TB) in camels has not been extensively studied in Nigeria. Camels in the hands of Nigerian pastoralists...  相似文献   
83.

A total of 1000 clinically healthy small ruminants comprising 500 sheep and 500 goats from five districts within Riyadh Province in Saudi Arabia were investigated by routine Giemsa staining for hematozoan parasites. Out of these, 100 sheep and 95 goat samples were investigated by PCR using three pairs of hemoprotozoan-specific primers. Based on microscopic examination, 33.2% of sheep and 25.2% of goats were found infected with hemoprotozoan parasites, while PCR detected hematozoan infection in 46% of sheep and 33.7% of goats. Extensive molecular characterization of hematozoan infection using six pairs of species-specific primers revealed the dominance of Theileria ovis, rather than any other species, which is recorded for the first time in small ruminants in Saudi Arabia. Prevalence of T. ovis in sheep and goats was found to be the highest in Riyadh (32, 48%) followed by AL-Kharj (31, 35%), Ad-Dawadimi (31, 33%), AL-Majmaah (15, 27%), and Rumah (17, 23%). The highest parasite prevalence was recorded in the 3 years of age and >?4 years of age ruminants, while the lowest prevalence was recorded in <?1 year of age ruminants. No noticeable differences in parasite prevalence between male or female ruminants were recorded. Partial sequencing of 18S rRNA gene revealed the infection of the studied ruminants with four new isolates of T. ovis. Further characterization of the pathogenicity and the clinical effects of these T. ovis isolates in sheep and goats is highly needed. The current results can be helpful in protecting and improving livestock industry in the countries that depend on a high number of small ruminants.

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84.

In the next two decades, the world population will increase significantly; the majority in the developing countries located in the tropics of Africa, Asia, Latin America, and the Caribbean. To feed such a population, it is necessary to increase the availability of food, particularly high-value animal protein foods produced locally, namely meat and dairy products. Dairy production in tropical regions has a lot of growth potential, but also poses a series of problems, particularly as dairy production systems were developed in temperate countries and in most cases are difficult to implement in the tropics. Drawbacks include hot weather and heat stress, the lack of availability of adequate feeds, poor infrastructure, and cold chain and the competition with cheap imports from temperate countries. This position paper reviews the major drawbacks in dairy production for the five major dairy species: cattle, water buffalo, sheep, goat, and camel, as well as the future trends in research and development. It also concerns the major trends in reproduction and production systems and health issues as well as environmental concerns, particularly those related to greenhouse gas emissions. Tropical Animal Health and Production now launches a topical collection on Tropical Dairy Science. We aim to publish interesting and significant papers in tropical dairy science. On behalf of the editorial board of the Tropical Animal Health and Production, we would like to invite all authors working in this field to submit their works on this topic to this topical collection in our journal.

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85.
In this study, energy use patterns and the functional relationship between energy inputs and output for pomegranate production were investigated in Antalya province in Turkey. It further objective to identify greenhouse gas (GHG) emissions in pomegranate production. Data were obtained from 75 farms using face-to-face interview method. The results indicated that 50,605.5?MJ ? ha?1 of total energy input was required for 76,252.3?MG ? ha?1 pomegranate energy output. 1.51 unit energy output was provided by using 1 unit energy input. 1 unit energy output and 1?kg pomegranate require 0.66 unit and 2.57?MJ energy input, respectively. The average CO2 emission amounts were also calculated to be 1.73?t CO2 per hectare and 88.1?kg CO2 per 1000?kg pomegranate production. Electricity, fertilizers and pesticides were the highest contributors to GHG emissions. Both total energy input usage and GHG emission amounts have been found to be decreasing as the farm size increases. Increasing scale of pomegranates orchards will not only increase energy efficiency and productivity but also decrease environmental pollution and damages. The regression analysis revealed that, excessive use of machinery and fuel inputs results in a decline in energy production in pomegranate.  相似文献   
86.
87.
The frequencies of B-alleles in RDM were analysed in samples of 637 bulls born in 1963–64–65, 794 bulls born in 1960–61–62 and 1226 cows from common herds.Among the 46 distinct alleles for which frequencies were estimated only about 10 alleles have frequencies above 1 %. The frequency of some alleles shows consistent variations during the last 10–15 years.The degree of homozygosity at the B-locus has remained almost constant among bulls during the last 10–15 years, while the homozygosity among cows from common herds shows a decreasing tendency.  相似文献   
88.
In a search for alternative, environmentally friendly and effective disinfecting agents, a commercially available protease—Neutrase®—was tested in this work for inactivation of koi herpesvirus (KHV) and of viral haemorrhagic septicaemia virus (VHSV). For comparison, the stability of these viral pathogens in similar configurations at various pH values and concentrations of peracetic acid or quicklime, typically used for disinfection, was tested. Therefore, virus suspensions were incubated with various concentrations of different agents for 24 hr and the titre of the remaining infectious particles was determined by virus titration. Furthermore, the treatment of both viruses, with the agents at concentrations that were previously appointed as effective, was also examined in the presence of solid material (quartz sand). All procedures investigated in this study, including the protease treatment, were able to reduce the titre of KHV and VHSV below the detection limit of the titration. Although further studies are necessary, this is the first report of the application of a protease for the inactivation of the selected fish pathogens, demonstrating the great potential of the latter for disinfection.  相似文献   
89.
Toxoplasma gondii consists of three genotypes, namely genotype I, II and III. Based on its virulence, T. gondii can be divided into virulent and avirulent strains. This study intends to evaluate an alternative method for predicting T. gondii virulence using hierarchical cluster analysis based on complete coding sequences (CDS) of sag1, gra7 and rop18 genes. Dendrogram was constructed using UPGMA with a Kimura 80 nucleotide distance measurement. The results showed that the prediction errors of T. gondii virulence using sag1, gra7 and rop18 were 7.41%, 6.89% and 9.1%, respectively. Analysis based on CDS of gra7 and rop18 was able to differentiate avirulent strains into genotypes II and III, whereas sag1 failed to differentiate.  相似文献   
90.
Soybean root rot is a worldwide soil-borne fungal disease threatening soybean production, causing large loss in yield and quality of soybean. Fusarium species are well recognized as the important causal agent of Fusarium root rot, which are often distinct with respect to various factors in different soybean-producing regions around the world. Recently, Fusarium root rot has been frequently reported in Sichuan Province of China, where is unique in its climate and diverse cropping patterns, but it is still unclear about the predominant Fusarium species and their pathogenicity on soybean. In this study, diseased soybean roots were collected from three regions of Sichuan Province during 2014–2015. Based on morphological characteristics and phylogenetic analysis of nucleotide sequences of the ribosomal internal transcribed spacer region and the translation elongation factor 1-α gene, 78 isolates of Fusarium were identified as nine distinct species. Pathogenicity tests showed that seven species of Fusarium were able to infect soybean, but differed in pathogenicity. F. oxysporum, F. equiseti and F. graminearum were the most aggressive species to soybean, whereas F. fujikuroi and F. verticillioides were not pathogenic to soybean. There was a strong positive correlation of the pathogenicity of Fusarium species with seedling emergence and fresh root weight. In addition, the diversity of Fusarium species varied among soybean-growing regions. To our knowledge, this report on population and pathogenicity of Fusarium species, in particular, F. graminearum, associated with soybean root rot in Sichuan Province of southwest China, will be helpful to provide effective control strategies for the disease.  相似文献   
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