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The influence of meat storage atmosphere on the quality parameters
2017
Fathy A. Khalafalla | Abdelrahim H.A. Hassan | Rabab A-H. Ali
This study was carried out to assess the effect of storage conditions on the sensory, quality parameters and microbiological status of beef from the muscle “Semitendinosus”. The experiment was design into 4 groups of beef samples, the first was control and the others were unpacked, aerobic packed and vacuum packed chilled meat. The obtained results showed that the mean values of mesophilic counts were 6×10⁷±5×10⁶, 3×10⁷±3×10⁶, 3×10⁷±2×10⁶ and 5×10⁷±5×10⁶ CFU/g, while those of psychrophilic count were 5×10⁷±5×10⁶, 3×10⁶±3×10⁵, 4×10⁶±3×10⁵ and 7×10⁶±7×10⁵ CFU/g, whereas the mean values of coliforms MPN were 10⁵±10⁴, 10⁵±10⁴, 2×10⁴±10³ and 4×10⁷±2×10⁶ MPN/g, the mean values of fecal coliforms MPN were 2×10³±2×10², 4×10⁴±3×10³, 2×10³±10² and 10⁷±10⁶ MPN/g, the mean values of E. coli MPN were 9×10²±9×10, 6×10±6×10², 6×10³±10² and 2×10³±10² MPN/g and the mean values of Staphylococcus count were (9×10⁵±9×10⁴, 10⁶±10⁵, 2×10⁶±10⁵ and 2×10⁶±2×10⁵ CFU/g) for control, unpacked, aerobic packed and vacuum packed chilled stored beef, respectively. The unpacked meat showed increase in shelf life time till four days as the sensory evaluation become excellent till four days also, increased pH, drip, water holding capacity (WHC) and cooking loss at four days. Staphylococcus reach to unsatisfactory level. Area packed meat increase in shelf life time till six days showing excellent sensory evalution at six day, decreasd drip, water holding capacity and cooking loss and slowly increased in bacterial count. Anaerobic meat have the longest shelf life time till 10 days as vacuum packing reduce drip, WHC and cooking loss. Also decrease mesophilic, fecal coliform growth. The quality assurance of cold storage was discussed as well as the vacuum packaged chilled beef has long shelf –life time than aerobic packed and fresh meat. This attributed to that package and cold storage reduce microbiological and physio-chemical alterations in meat. The recommendations to extension of shelf life time were discussed.
Afficher plus [+] Moins [-]Efficacy of a novel foot pan in biosecurity protocols for control of salmonellae in poultry farms
2017
Ehsan Y. Bashandy | Soad A. Nasef | Shimaa A.E. Nasr | May F. AbdElAty | Osama M.K. Zahran
This study aimed to replace liquid foot pan in the poultry farm, with a novel model that is used more effectively in biosecurity program convenient with the workers in Egyptian farms that avoid foot pan. This novel model dry foot pan, semiliquid (wet) foot pan and floor mat that enabled the disinfectants to be worked for a longer time. In the present study authors are looking for a durable footbath, stable, fast, easily applied and log acting in the reduction of salmonellae. The efficacy of powder disinfectant (calcium hypochlorite powder, Halamid, Staldren, Virkon S and paraformaldehyde) were tested against salmonellae in a novel form of foot pan dry, semi-liquid and floor mat models. The disinfectants were diluted by calcium carbonate or sodium chloride powder in the dry form, surfactant in the semiliquid form and use of the sponge as a mat in the third form. Daily measurement of the active principle of the tested disinfectants and the log reduction of the Salmonellae were done. The dry form and semi liquid form of the Calcium hypochlorite was successfully effective for 10 days in dry form and 9 days in semiliquid form. However, Halamid and Staldren were successfully effective in dry form for 14 days and 17 days respectively, semiliquid form was worked for 21 day and 3 days and floor mat was effective for 21 days and 3 days respectively. Paraformaldehyde powder was also effective for 6 days in the dry form, but in the semiliquid form was effective for 10 days, floor mat was effective for 12 days. 5% Virkon S could be effective for 3 days in the dry form and semi-liquid form but only 2 days in the floor mat form.
Afficher plus [+] Moins [-]Comparison of three nucleic acid-based tests for detecting Anaplasma marginale and Anaplasma centrale in cattle
2017
Chaisi, Mamohale E.(University of Pretoria Department of Veterinary Tropical Diseases) | Baxter, Janine R.(University of Pretoria Department of Veterinary Tropical Diseases ,University of Pretoria Department of Genetics) | Hove, Paidashe(University of Pretoria Department of Veterinary Tropical Diseases ,Agricultural Research Council) | Choopa, Chimvwele N.(University of Pretoria Department of Veterinary Tropical Diseases ,Ministry of Agriculture and Livestock Department of Veterinary Services) | Oosthuizen, Marinda C.(University of Pretoria Department of Veterinary Tropical Diseases) | Brayton, Kelly A.(University of Pretoria Department of Veterinary Tropical Diseases ,Washington State University Department of Veterinary Microbiology and Pathology) | Khumalo, Zamantungwa T.H.(University of Pretoria Department of Veterinary Tropical Diseases) | Mutshembele, Awelani M.(National Zoological Gardens) | Mtshali, Moses S.(National Zoological Gardens) | Collins, Nicola E.(University of Pretoria Department of Veterinary Tropical Diseases)
Several nucleic acid-based assays have been developed for detecting Anaplasma marginale and Anaplasma centrale in vectors and hosts, making the choice of method to use in endemic areas difficult. We evaluated the ability of the reverse line blot (RLB) hybridisation assay, two nested polymerase chain reaction (nPCR) assays and a duplex real-time quantitative polymerase chain reaction (qPCR) assay to detect A. marginale and A. centrale infections in cattle (n = 66) in South Africa. The lowest detection limits for A. marginale plasmid DNA were 2500 copies by the RLB assay, 250 copies by the nPCR and qPCR assays and 2500, 250 and 25 copies of A. centrale plasmid DNA by the RLB, nPCR and qPCR assays respectively. The qPCR assay detected more A. marginale- and A. centrale-positive samples than the other assays, either as single or mixed infections. Although the results of the qPCR and nPCR tests were in agreement for the majority (38) of A. marginale-positive samples, 13 samples tested negative for A. marginale using nPCR but positive using qPCR. To explain this discrepancy, the target sequence region of the nPCR assay was evaluated by cloning and sequencing the msp1β gene from selected field samples. The results indicated sequence variation in the internal forward primer (AM100) area amongst the South African A. marginale msp1β sequences, resulting in false negatives. We propose the use of the duplex qPCR assay in future studies as it is more sensitive and offers the benefits of quantification and multiplex detection of both Anaplasma spp.
Afficher plus [+] Moins [-]B-cell epitopes of African horse sickness virus serotype 4 recognised by immune horse sera
2017
Mathebula, Evans M.(Onderstepoort Veterinary Institute Agricultural Research Council ,University of Pretoria Department of Veterinary Tropical Diseases) | Faber, Frederika E.(Onderstepoort Veterinary Institute Agricultural Research Council) | van Wyngaardt, Wouter(Onderstepoort Veterinary Institute Agricultural Research Council) | van Schalkwyk, Antoinette(Onderstepoort Veterinary Institute Agricultural Research Council) | Pretorius, Alri(Onderstepoort Veterinary Institute Agricultural Research Council ,University of Pretoria Department of Veterinary Tropical Diseases) | Fehrsen, Jeanni(Onderstepoort Veterinary Institute Agricultural Research Council ,University of Pretoria Department of Veterinary Tropical Diseases)
Identifying antigenic proteins and mapping their epitopes is important for the development of diagnostic reagents and recombinant vaccines. B-cell epitopes of African horse sickness virus (AHSV) have previously been mapped on VP2, VP5, VP7 and NS1, using mouse, rabbit and chicken monoclonal antibodies. A comprehensive study of the humoral immune response of five vaccinated horses to AHSV-4 antigenic peptides was undertaken. A fragmented-genome phage display library expressing a repertoire of AHSV-4 peptides spanning the entire genome was constructed. The library was affinity selected for binders on immobilised polyclonal immunoglobulin G (IgG) isolated from horse sera collected pre- and post-immunisation with an attenuated AHSV-4 monovalent vaccine. The DNA inserts of binding phages were sequenced with Illumina high-throughput sequencing. The data were normalised using pre-immune IgG-selected sequences. More sequences mapped to the genes coding for NS3, VP6 and VP5 than to the other genes. However, VP2 and VP5 each had more antigenic regions than each of the other proteins. This study identified a number of epitopes to which the horse's humoral immune system responds during immunisation with AHSV-4.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
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