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Detection of natural <i>Trypanosoma vivax</i> infections in pigs with microhaematocrit centrifugation and amplification of ITS1 rDNA Texto completo
2009
S. Biryomumaisho | S.E. Melville | E. Katunguka-Rwakishaya | G.W. Lubega
Different species of trypanosomes may infect their mammalian hosts both singly or in combination. This study was undertaken to determine the trypanosome species that may be afflicting pigs in Uganda. Blood was collected from pigs of all ages and sexes from two districts, Kasese in Western and Jinja in Central Uganda. Of the 133 pig blood samples from Kasese that were tested for trypanosomes using the microhaematocrit centrifugation technique (MHCT), none was found to be infected. However, of the 253 pigs from Jinja district, nine were infected with trypanosomes of which three had T. vivax as determined by MHCT. However, application of the ITS1 rDNA PCR test revealed that eight pigs had T. vivax in mixed infections and one pig had T. vivax monolithic infection. These observations show that under certain circumstances, pigs may be important reservoirs for, as well as hosts to, T. vivax, contrary to earlier reports.
Mostrar más [+] Menos [-]Studies on the cumulative effect of sodium thiomersal on broilers vaccinated with inactivated poultry vaccines Texto completo
2009
Zeinab M. Sror | Anhar Abd El-Moety | Hanan, M. Ibrahim | M. L. Sayed, A. R. Mahmoud | A. R. Mahmoud | S. M. Shafei | M. H. Khodeir
Merthiolate (Thiomersal) is known to be used as antimicrobial agent in inactivated vaccines without affecting vaccine potency. The present work investigated the effect of thiomersal contents in ND, AI and IBD inactivated vaccines on liver and kidney functions of vaccinated birds. The histopathological effect and the withdrawal time of such mercurial product from vaccinated chicken muscles were also investigated. Results revealed that residual thiomersal contents in ND, AI and IBD were 0.03; 0.02 and 0.03mg/ml respectively. Liver and kidney function parameters showed significant increases in serum activities of alanine aminotransferase (ALT) and serum aspartate aminotransferase (AST) up to the 4th week post vaccination. Serum urea was significantly decreased on the 3rd week in vaccinated birds compared to control ones. Significant increase in serum creatinine in vaccinated chickens was recorded on the 5th week post vaccination. Liver and kidney functions’ parameters remain high allover the experimental period (8 weeks). The histopathological examination of liver specimens revealed degeneration of hepatic cells and congestion of the central vein with inflammatory cell infiltration and congestion of blood vessels as well as coagulative necrosis. The spleen of vaccinated chickens showed depletion of lymphocytes while lungs showed thickening of the alveolar. Mercury contents in muscle were 0.72, 0.52; 0.046 and 0.00 mg/kg on the 1st, 2nd, 3rd and 4th week post last vaccination that considered safe to the consumer. It is recommended that vaccinated poultry with inactivated vaccines containing thiomersal should not be slaughtered before at least 4 weeks and it is preferable to use combined inactivated vaccines to reduce the thiomersal contents as possible.
Mostrar más [+] Menos [-]Field study on control of chronic respiratory disease in vertically infected broiler chicks Texto completo
2009
M. M. Amer | K. M. El-Bayomi | Zenab, M. S. Gera | A. E. A. Hanafei
Our field studies had been carried out after in vitro antibiogram of E. coli to compare the effect of pulmotil (macroloide), enerofloxacin (fluoroquinolones) and doxycycline (tetracycline) in controlling mycoplasma and E. coli as a cause of CRD in broilers. The drugs were used in single or in combination. Two doses at the 3rd and 23rd day of age on performance of commercial broiler Ross derived from mycoplasma SPA-test positive breeders and E. coli positive isolation at the 1st day of age. The prevalence of marked air sac gross lesions in non treated control group indicated the development of CRD and severity of lesions increased with age. The used drugs played a role in controlling infection as treated groups showed milder lesions while more sever lesions were in doxycycline treated group. Protection against mortality was less in the treated pins than untreated ones. Cumulative culls % was low (1.1) in pen treated with enrofloxacin, (1.5) in pulmotil + enrofloxacin, (1.6) in doxycycline, and (1.7) in pulmotil + enrofloxacin; while pulmotil and control were the same (2.2%). Losses expressed as total mortality and culls % were the lowest in pulmotil + enrofloxacin and enrofloxacin (3.2 and 3.6), other treated pins showed the same values (4.2), while the highest was in non treated ones (5.8%). Average Body wt. in pulmotil + enrofloxacin, pulmotil, and enrofloxacin treated pens were higher (1934, 1924 and 1819 gm) than doxycycline (1802 gm), Pulmotil + Doxycycline (1705 gm) and non treated control (1708 gm). CFCR in pulmotil or enrofloxacin and in combination medicated pens were higher than other treatments and non medicated pen. Average day/ week/ gain in control non treated was equal to that of pulmotil or enrofloxacin (65g), slight lower value was in their combination (63g) followed by 58 g in doxycycline. The lowest ADG /w/g value was in pulmotil + doxycycline (52 g). Calculated EEF of treated and non medicated pens were higher than > 280. The medicated pens with either pulmotil or/ enrofloxacin and there compilation were superior (333, 313 and 330; respectively) and close to the farm stander (346). This study pointed out that E. coli, and Mycoplasma with life ND vaccine reduced broiler performance and the used drugs were of values in control such infections. The in vitro antibiotics sensitivity testing of E. coli is important to obtain good results and drug combinations must be carefully performed.
Mostrar más [+] Menos [-]In vivo and in vitro study on the effect of Bacillus subtilis and its byproducts on Clostridium perfringens Type A Texto completo
2009
I. A. Radwan | Eman R. Hassan
The objectives of this study were to screen the possible effects of B. subtilis and its soluble byproducts against C. perfringens, a causative agent of necrotic enteritis (NE) in chickens. The use of B. subtilis strain was found to be inactive in vitro against C. perfringens but its cell filtrate byproducts produced after growth of B. subtilis at 37°C with medium pH adjusted at 5.0, having inhibitory effect in the form of inhibitory zones; measured inhibition of 12 mm. The produced anticlostridial factor was not affected by heat treatment at 70, 100 or 121°C for 15 minutes. The study recorded the responses of broiler chickens to oral administration of C. perfringens and the possible antagonistic effects of B. subtilis and its cell-free filtrate byproducts in vivo. Results revealed that B. subtilis decreased the severity of intestinal necrotic lesions produced after oral inoculation of C. perfringens and the suggested anticlostridial effect was more clear when the cell- free filtrate produced by growing B. subtilis at 37°C with pH 5.0 was added to feed at a dose of 20 ml/kg of ration.
Mostrar más [+] Menos [-]Impact of age at first calving on reproduction, lactation, postpartum disorders and longevity in Holsteins under Egyptian circumstances Texto completo
2009
M. M. Hussein | A. A. A. El Agawany
A retrospective study including reproductive and productive data of 1587 primiparous Holstein cows covering a period of eight years. The reproductive data ( interval to 1st service, service period, days open, number of inseminations per conception and calving interval ) and the productive data ( total milk yield, average daily milk yield and 305 day milk yield) were studied as a function of age at first calving and postpartum disorders. Furthermore, other data including life span longevity, number of parities, the cumulative productive days and the average calving interval were also studied as a function of age at first calving. Cows were classified according to the age at first calving into young age calvers (< 24 months), mid age calvers (> 24-28 months) and old age calvers (> 28 months). The obtained data were statistically analyzed, tabulated and discussed. The overall mean age at first calving was 26.68 months in Holstein cows under Egyptian circumstances. Most of first calving (90%) were recorded in cows less than 30 month of age. The results indicated that, the young age calvers tend to have prolonged interval to 1st service, days open and calving interval and the reverse was correct in old age calvers. The postpartum disorders had significantly detrimental effects on the reproductive performance among the different age groups. Young age calvers had a higher incidence of postpartum disorders than those of mid - age calvers and much higher than had the old age group. The postpartum disorders were associated with high milk production specially in mid and old age calvers which may indicate the high predisposition of superior producer cows to postpartum disorders. Life span, longevity, number of parities and the cumulative production days were found to be increased as a function of age at first calving. Meanwhile, the average calving interval of the young age calvers was longer than the other two age groups. Finally, it was recommended to avoid insemination of maiden Holstein heifers less than 17 month of age specially those having superior productive traits.
Mostrar más [+] Menos [-]Rinderpest : an historical overview : historical overview : Onderstepoort and veterinary research in Africa Texto completo
2009
P. Roeder
Rinderpest is one of the few diseases which have changed the course of world history. Originally an Asian disease, for centuries it had a devastating impact in Europe when introduced by returning and marauding armies accompanied by cattle as well as by cattle trade. Nowhere was its impact more dramatically expressed than in Africa where the sequel to its introduction into the Horn of Africa was a devastating panzootic throughout sub-Saharan Africa during the last decade of the 19th century extending into the 20th century. Massive deaths of livestock, wild animals and the people dependent on them led to widespread human misery and changed the face of the African continent forever.
Mostrar más [+] Menos [-]History of bluetongue research at Onderstepoort : transboundary diseases Texto completo
2009
D.W. Verwoerd
Research on this economically important disease of ruminants, especially sheep, which had been named bluetongue by farmers in the 19th century, has been part and parcel of the activities at Onderstepoort ever since its establishment in 1908 and therefore covers a full century of the OVI's existence. In view of Onderstepoort's centenary celebration a brief overview of this research is given in terms of the historic milestones which influenced and guided global research on this and other viral diseases of animals.
Mostrar más [+] Menos [-]Sir Arnold Theiler and the discovery of anaplasmosis : a centennial perspective : tick-borne diseases Texto completo
2009
G.H. Palmer
Sir Arnold Theiler's research in 1908/09 led to the discovery of the first rickettsial pathogen, Anaplasma marginale, and set the stage for his development and implementation of an effective live vaccine based on a less virulent strain, A. marginale ss. centrale. His 1910 report, describing A. marginale, is among the classic monographs in infectious disease research, presenting not only observations in exacting detail but also highlighting the deductive reasoning leading to association of a new pathogen with a specific disease. With a centennial perspective and both conceptual frameworks and molecular tools unimaginable in Theiler's time, the significance of several observations in the original report - cyclic bacteremia, strain superinfection, and taxonomic position - is now clear and highlight the broad applicability of key principles of pathogen biology.
Mostrar más [+] Menos [-]Some anatomical studies on the nerve supply of the tail of the buffalo ”Bos Bubalis L. ” Texto completo
2009
Z. A. Adam | M. G. Tawfiek | M. R. A. Gad
Ten tails of buffaloes were used in this study from apparently healthy adult animals. They were dissected to reveal their nerve supply. Eight photographs illustrated the results in the study. The study revealed that there are five pairs of caudal nerves, sympathetic and parasympathetic innervations of the tail are demonstrated.
Mostrar más [+] Menos [-]Tsetse and trypanosomosis in Africa : the challenges, the opportunities : vector-borne diseases : trypanosomosis Texto completo
2009
A.A. Ilemobade
Tsetse-fly and the disease it transmits, trypanosomosis, remain an enormous disease challenge in the 37 countries of sub-Saharan Africa where the impact continues to be manifest in disease burden, increased level of poverty and decreased agricultural productivity. The impact also extends over an estimated 10 million km2 (a third of the African continent) of land area, a third of which contains some well-watered part of the continent, thus denying humans and livestock of potentially rich arable and pastureland.
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