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Epidemiology and effect of gastrointestinal nematodes on dairy goats in Argentina
2017
Suarez, Victor H.(Centro de Investigaciones Agropecuarias Instituto Nacional de Tecnología Agropecuaria) | Martínez, Gabriela M.(Centro de Investigaciones Agropecuarias Instituto Nacional de Tecnología Agropecuaria) | Viñabal, Alberto E.(Centro de Investigaciones Agropecuarias Instituto Nacional de Tecnología Agropecuaria) | Alfaro, José R.(Centro de Investigaciones Agropecuarias Instituto Nacional de Tecnología Agropecuaria)
The aim of this work was to study the epidemiology and harmful effects of gastrointestinal nematodes (GINs) on dairy goats maintained in an intensive system. Two groups of goats were studied: untreated group (UG) (subdivided into UGjun goats that kidded in June, and UGjul goats that kidded in July) and treated group (TG) (with no subgroups, treated with monepantel: 3.75 mg/kg, orally, monthly). Eggs per gram (epg) in faeces were counted, faecal culture was performed to differentiate nematode genera and milk production was measured. Differences between groups were compared using least squares means analysis of variance (milk production and milking period length) and Kruskal-Wallis test (faecal egg counts). Nematode infection was moderate, with Haemonchus and Trichostrongylus being the dominant genera; the faecal egg counts reached the level of 2000 only once throughout the study. Goats that kidded in June had higher egg count after parturition (UGjun = 1564 epg), with significant differences (p < 0.04) from those that still had not kidded (UGjul = 962 epg). Over the entire trial period, the mean total milk production of TG (399.5 L ± 34.0 L) was significantly higher (p < 0.05) than that of UG (281.6 L ± 37.5 L), representing an increase of 41.8% in total milk yield. The results of this study show a post-partum peak in egg count and a negative effect of GINs on milk yield, even with moderate infections.
Mostrar más [+] Menos [-]History of Newcastle disease in South Africa
2017
Abolnik, Celia(University of Pretoria Department of Production Animal Studies)
Poultry production in South Africa, a so-called developing country, may be seen as a gradient between two extremes with highly integrated commercial enterprises with world-class facilities on one hand and unimproved rural chickens kept by households and subsistence farmers on the other. Although vaccination against Newcastle disease is widely applied to control this devastating infection, epizootics continue to occur. Since the first official diagnosis in 1945, through the sporadic outbreaks of the 1950s and early 1960s, to serious epizootics caused by genotype VIII (late 1960s-2000), genotype VIIb (1993-1999), genotype VIId (2003-2012) and most recently genotype VIIh (2013 to present), South Africa's encounters with exotic Newcastle disease follow global trends. Importation - probably illegal - of infected poultry, poultry products or exotic birds and illegal swill dumping are likely routes of entry. Once the commercial sector is affected, the disease spreads rapidly within the region via transportation routes. Each outbreak genotype persisted for about a decade and displaced its predecessor.
Mostrar más [+] Menos [-]Prevalence and renal pathology of pathogenic Leptospira spp. in wildlife in Abeokuta, Ogun State, Nigeria
2017
Ajayi, Olusola L.(Federal University of Agriculture Department of Veterinary Pathology) | Antia, Richard E.(University of Ibadan Department of Veterinary Pathology) | Ojo, Olufemi E.(Federal University of Agriculture Department of Veterinary Microbiology and Parasitology) | Awoyomi, Olajoju J.(Federal University of Agriculture Department of Veterinary Public health and Reproduction) | Oyinlola, Latifa A.(Federal University of Agriculture Department of Food Science and Technology) | Ojebiyi, Oluwabusola G.(Federal University of Agriculture Department of Veterinary Pathology)
There is paucity of information on the prevalence of leptospirosis in wildlife in Nigeria. This study investigated the prevalence and renal pathology of leptospirosis in wild animals in Southwest Nigeria. One hundred and five kidney samples were examined from 10 different wildlife species (antelope) greater cane rat (GCR), hare, African giant rat (AGR), tree hyrax, civet cat, monitor lizard, python, bushbuck and partridge) using a combination of Ellinghausen McCullough Johnson Harris (EMJH) medium, microscopic agglutination test (MAT), Warthin-Starry silver stain (WSss) and immunohistochemistry. Chi-square test was used with confidence level set at 0.05 to ascertain associations between positive cases and sex and species. Eighty-two (78.1%) samples were culturally positive, while 67.7% (63/93), 57.0% (16/28) and 66.7% (8/12) were WSss, MAT and immunohistochemically positive, respectively. Interstitial nephritis (41.0%) and tubular nephrosis (81.0%) were the most prominent histopathological changes. Pathogenic Leptospira organisms were highest in GCR (32.1%) and antelope (14.3%). Serovars hardjo (11.54%), bratislava (3.9%), canicola (3.9%), icterohaemorrhagiae (15.4%), pomona (7.14%) gripptotyphosa (19.2%) and undetermined isolates were also detected in other animals. The result showed high prevalence of Leptospira infection in the wild and the possibility of domestic animals and humans contracting the disease. This study is the first documentation of evidence of pathogenic Leptospira species in wildlife in Nigeria.
Mostrar más [+] Menos [-]Evaluation of plant-produced Clostridium perfringens type D epsilon toxoid in a vaccine against enterotoxaemia in sheep
2017
Mokoena, Tinyiko(Council for Scientific and Industrial Research ,University of Pretoria Forestry and Agricultural Biotechnology Institute Department of Plant Science) | Chakauya, Ereck(Council for Scientific and Industrial Research) | Crampton, Michael(Council for Scientific and Industrial Research) | Weyers, Boet(Onderstepoort Biological Products) | Tselanyane, Malefa(Council for Scientific and Industrial Research) | Tsekoa, Tsepo(Council for Scientific and Industrial Research) | Chikwamba, Rachel(Council for Scientific and Industrial Research)
Enterotoxaemia (pulpy kidney) is a common bacterial disease of sheep caused by Clostridium perfringens type D epsilon toxin. It has mortality rates of up to 30% in non-vaccinated animals. Current vaccines from whole cell cultures are expensive to manufacture and can induce local inflammatory responses in sheep. They usually have reduced immunogenicity because of the difficulty of standardising the inactivation step in vaccine manufacturing. In the current study, we evaluated the safety and potency of a recombinant plant-made epsilon toxoid protein (r-Etox) as an affordable and safer alternative vaccine for developing countries. Results of injection site reactions, rectal temperature and toxin neutralisation test in single and prime-boost inoculations of mice, guinea pigs and sheep suggest that the product is not toxic to animals and could protect sheep against enterotoxaemia.
Mostrar más [+] Menos [-]Emerging vector-borne diseases in dromedaries in Tunisia: West Nile, bluetongue, epizootic haemorrhagic disease and Rift Valley fever
2017
Hassine, Thameur B.(Université la Manouba Ecole Nationale de Médecine Vétérinaire de Sidi Thabet) | Amdouni, Jihane(Université Tunis El Manar Institut de la Recherche Vétérinaire de Tunisie) | Monaco, Federica(Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise) | Savini, Giovanni(Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise) | Sghaier, Soufien(Université Tunis El Manar Institut de la Recherche Vétérinaire de Tunisie) | Selimen, Imed B.(Commissariats Régionaux au Développement Agricole) | Chandoul, Walid(Commissariats Régionaux au Développement Agricole) | Hamida, Khaled B.(Université Tunis El Manar Institut de la Recherche Vétérinaire de Tunisie) | Hammami, Salah(Université la Manouba Ecole Nationale de Médecine Vétérinaire de Sidi Thabet ,Université Tunis El Manar Institut de la Recherche Vétérinaire de Tunisie)
A total of 118 sera were collected during 2016 from two groups of dromedaries from Kebili and Medenine governorates in the south of Tunisia. The aim of this study was to provide the first serological investigation of four emerging vector-borne diseases in two groups of dromedaries in Tunisia. Sera were tested by ELISA and serum neutralisation test to identify West Nile virus (WNV), bluetongue virus (BTV), epizootic haemorrhagic disease virus (EHDV) and Rift Valley fever virus (RVFV). In the first group, the seroprevalence for BTV was 4.6%, while in the second group, it was 25.8% for WNV and 9.7% for BTV. Only serotype 1 was detected for BTV in the two groups. No evidence for circulation of RVF and EHD viruses was revealed. Results indicated that dromedaries can be infected with BTV and WNV, suggesting that this species might play a significant role in the epizootiology of these viral diseases in Tunisia and neighbouring countries.
Mostrar más [+] Menos [-]Epidemiological studies based on multi-locus sequence typing genotype of methicillin susceptible Staphylococcus aureus isolated from camel's milk
2017
Ali, Alsagher O.(South Valley University Animal Medicine Department Division of infectious Diseases) | Mahmoud, Hassan Y.A.H.(South Valley University Animal Medicine Department Division of infectious Diseases)
One hundred milk samples were collected from camel's milk for the isolation of Staphylococcus aureus. Thirty-one isolates were S. aureus, 45 were other forms of staphylococci and 24 represented other bacteria. Five isolates from S. aureus were methicillin resistant S. aureus (MRSA) and 26 samples were methicillin susceptible S. aureus (MSSA). The whole genome sequence of S. aureus was annotated and visualised by rapid annotation using subsystem technology (RAST) which is a fully-automated service for annotating complete or nearly complete bacterial genomes. Four isolates from MSSA strains were subjected to multi-locus sequence typing (MLST). Three multi-locus sequences types or sequence types (MLST/ST) were found, namely ST15, ST1153 and ST130. The phylogenetic analysis of the concatenated sequences of the seven genes forming the MLST profile of S. aureus classification revealed a high degree of similarity and close relationship between the ST15 and ST1153 while the third ST (ST130) was located in a different cluster.
Mostrar más [+] Menos [-]A retrospective study of anthrax on the Ghaap Plateau, Northern Cape province of South Africa, with special reference to the 2007-2008 outbreaks
2017
Hassim, Ayesha(University of Pretoria Department of Veterinary Tropical Diseases) | Dekker, Edgar H.(South Africa Department of Agriculture, Forestry and Fisheries) | Byaruhanga, Charles(University of Pretoria Department of Veterinary Tropical Diseases) | Reardon, Tommy(South Africa Department of Agriculture, Forestry and Fisheries) | van Heerden, Henriette(University of Pretoria Department of Veterinary Tropical Diseases)
Anthrax is a zoonotic disease caused by the gram-positive, endospore-forming and soil-borne bacterium Bacillus anthracis. When in spore form, the organism can survive in dormancy in the environment for decades. It is a controlled disease of livestock and wild ungulates in South Africa. In South Africa, the two enzootic regions are the Kruger National Park and the Ghaap Plateau in the Northern Cape province. Farms on the Plateau span thousands of hectares comprising of wildlife - livestock mixed use farming. In 2007-2008, anthrax outbreaks in the province led to government officials intervening to aid farmers with control measures aimed at preventing further losses. Because of the ability of the organism to persist in the environment for prolonged periods, an environmental risk or isolation survey was carried out in 2012 to determine the efficacy of control measures employed during the 2007-2008, anthrax outbreaks. No B. anthracis could be isolated from the old carcass sites, even when bone fragments from the carcasses were still clearly evident. This is an indication that the control measures and protocols were apparently successful in stemming the continuity of spore deposits at previously positive carcass sites.
Mostrar más [+] Menos [-]Construction of a live attenuated Salmonella strain expressing FanC protein to prevent bovine enterotoxigenic Escherichia coli and evaluation of its immunogenicity in mice
2017
Won, G., Chonbuk National University, Iksan, Republic of Korea | Kim, H.J., Chonbuk National University, Iksan, Republic of Korea | Lee, J.H., Chonbuk National University, Iksan, Republic of Korea
To construct a novel vaccine candidate against bovine enterotoxigenic Escherichia coli (ETEC), FanC, the major subunit of K99 fimbriae adhesion, was inserted into secretion plasmid pYA3560 containing a β-lactamase secretion system. This was then transformed into Δasd Δcrp Salmonella (S.) Typhimurium and designated as JOL950. Secretion of recombinant fanC fimbrial antigens was confirmed by immunoblot analysis. Groups of mice were inoculated with single or double doses of JOL950. Another group was used as a negative control. Compared to control mice, all immunized mice had significantly higher levels (p less than 0.05) of serum immunoglobulin (Ig)G, and secretory IgA against FanC. The IgG2a and IgG1 titer assays revealed that immunization highly induced IgG2a compared to that of IgG1, indicating that T helper-1- related cell-mediated immune responses may be elicited by JOL950. The results show that both systemic and mucosal immunities against selected fimbrial antigens of bovine ETEC expressed by a live attenuated S. Typhimurium strain are prominently produced in mice immunized with JOL950 via an oral route.
Mostrar más [+] Menos [-]Improvement of indirect enzyme-linked immunosorbent assay for detection of Japanese encephalitis virus antibodies in swine sera
2017
Yang, D.K., Viral Disease Division,Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea | Kim, H.H., Viral Disease Division,Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea | Jo, H.Y., Viral Disease Division,Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea | Lee, S.H., Viral Disease Division,Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea | Jang, S.H., R and D Center, MEDIAN Diagnostics, Chuncheon, Republic of Korea | Lee, S.O., R and D Center, MEDIAN Diagnostics, Chuncheon, Republic of Korea | Choi, S.S., Viral Disease Division,Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea | Cho, I.S., Viral Disease Division,Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea
Japanese encephalitis (JE) is an important zoonosis caused by the mosquito-transmitted JE virus (JEV), which is a causative agent of reproductive failure in pregnant sows. Detection of JEV antibodies in swine is performed by hemagglutination inhibition (HI), virus neutralization (VN), and the plaque reduction neutralization test (PRNT). The most stringent PRNT is the 90% endpoint PRNT (PRNT∧90). These conventional assays are difficult to carry out in diagnostic laboratories with insufficient instruments or cell culture systems. An alternative assay that is easily conducted and time efficient is required. In this study, we improved the indirect enzyme-linked immunosorbent assay (I-ELISA) with clarified antigen for the detection of JEV antibodies. The I-ELISA results obtained from 175 swine serum samples were compared with HI, VN, and PRNT∧90 results. The sensitivity of I-ELISA was 91.8%, 95.0%, and 94.7% compared with HI, VN, and PRNT∧90 results, respectively. The specificity of I-ELISA was 92.2%, 94.7%, and 94.7% compared with HI, VN, and PRNT∧90 results, respectively. Moreover, the I-ELISA results were significantly correlated with the HI (r = 0.93), VN (r = 0.95), and PRN∧T90 (r = 0.92) results. These results suggest that the improved I-ELISA is useful for serosurveillance of JEV in swine.
Mostrar más [+] Menos [-]Dehydroepiandrosterone and cortisol concentrations in the cerebrospinal fluid of dogs
2017
Mongillo, P., University of Padova, Legnaro, Italy | Bernardini, M., University of Padova, Legnaro, Italy | Prana, E., University of Padova, Legnaro, Italy | Balducci, F., Portoni Rossi Veterinary Hospital, Zola Predosa, Italy | Gabai, G., University of Padova, Legnaro, Italy | Marinelli, L., University of Padova, Legnaro, Italy
Concentrations of cortisol, dehydroepiandrosterone and dehydroepiandrosterone-sulfate were measured by performing radioimmunoassay of the cerebrospinal fluid of 68 dogs diagnosed with idiopathic epilepsy or inflammatory, degenerative, or non-neurological disease. No steroid concentration differences were found among diagnoses. Dehydroepiandrosterone and dehydroepiandrosterone-sulfate concentrations were higher in males than in females and dehydroepiandrosterone-sulfate decreased with increasing age. No sex or age effects were observed on cortisol or hormone ratios. Although limited to a relatively small sample, our results show sex- and age-dependent variations in these neurosteroid concentrations in cerebrospinal fluid. The role of such variations in the pathophysiology of the dog brain warrants further investigation.
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