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Some macromorphological studies on the ventricular musculature of the heart of the donkey 全文
2007
S. A. Ragab | Y. R. Wally | F. M. Farag | M. A. N. M. Nazif
The present work was conducted on 25 hearts of healthy donkeys of both sexes. Three methods were adopted to clarify the musculature of the ventricles; nitric acid method, acetic acid method and flour paste method. The ventricular myocardium was arranged into three layers: superficial, middle and deep. The superficial layer consists of eleven bundles arranged longitudinally from the base to the apex of the heart. Moreover, a thin subepicardial layer separated it from the epicardium. The middle layer on the right ventricle was horizontally oriented, while on the left ventricle it was represented by three bands; (A), (B) and (C). The deep layer on the right ventricle was formed of two bands (A) and (B) while on the left ventricle consisted of a single band (C), in addition to some fibers derived from the superficial layer. The intervrentricular septum was formed from fibers extended from the middle and deep layers. The papillary muscles were four in the right ventricle and two in the left one.
显示更多 [+] 显示较少 [-]Antimicrobial activity of bovine bactericidal permeability-increasing protein-derived peptides against gram-negative bacteria isolated from the milk of cows with clinical mastitis 全文
2007
Chockalingam, A. | Zarlenga, D.S. | Bannerman, D.D.
Objective--To evaluate antimicrobial activity of bovine bactericidal permeability-increasing protein (bBPI)-derived synthetic peptides against mastitis-causing gram-negative bacteria. Sample Population--Bacterial isolates from the milk of cows with clinical mastitis. Procedures--3 peptides were synthesized with sequences corresponding to amino acids 65 to 99 (bBPI6599) or 142 to 169 (bBPI142169) or the combination of amino acids 90 to 99 and 148 to 161 (bBPI9099,148161) of bBPI. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of these peptides against bacterial isolates from cows with mastitis were determined by use of a standardized broth microdilution assay. The ability of these peptides to retain their antimicrobial activity in serum and milk was also evaluated. Finally, bacterial lipopolysaccharide (LPS)-neutralizing activity of these peptides was assayed with the Limulus amebocyte lysate test. Results--Of the 3 peptides tested, bBPI9099,148161 had the widest spectrum of antimicrobial activity, with MIC and MBC values ranging from 16 to 64 Mg/mL against Escherichia coli, Klebsiella pneumoniae, and Enterobacter spp and from 64 to 128 Mg/mL against Pseudomonas aeruginosa. None of the peptides had any growth-inhibitory effect on Serratia marcescens. The antimicrobial activity of bBPI9099,148161 was inhibited in milk, but preserved in serum. Finally, bBPI142169 and bBPI9099,148161 completely neutralized LPS. Conclusions and Clinical Relevance--bBPI9099,148161 is a potent neutralizer of the highly proinflammatory molecule bacterial LPS and has antimicrobial activity against a variety of gram-negative bacteria. The ability of bBPI9099,148161 to retain antimicrobial activity in serum suggests a potential therapeutic application for this peptide in the management of gram-negative septicemia.
显示更多 [+] 显示较少 [-]Ticks associated with the three largest wild ruminant species in Southern Africa 全文
2007
I.G. Horak | H. Golezardy | A.C. Uys
The objective of this study was to assess the host status of the three largest southern African wild ruminants, namely giraffes, Giraffa camelopardalis, African buffaloes, Syncerus caffer, and eland, Taurotragus oryx for ixodid ticks. To this end recently acquired unpublished data are added here to already published findings on the tick burdens of these animals, and the total numbers and species of ticks recorded on 12 giraffes, 18 buffaloes and 36 eland are summarized and discussed. Twenty-eight ixodid tick species were recovered. All stages of development of ten species, namely Amblyomma hebraeum, Rhipicephalus (Boophilus) decoloratus, Haemaphysalis silacea, Ixodes pilosus group, Margaropus winthemi, Rhipicephalus appendiculatus, Rhipicephalus evertsi evertsi, Rhipicephalus glabroscutatum, Rhipicephalus maculates and Rhipicephalus muehlensi were collected. The adults of 13 species, of which the immature stages use small mammals as hosts, namely Haemaphysalis aciculifer, Hyalomma glabrum, Hyalomma marginatum rufipes, Hyalomma truncatum, Ixodes rubicundus, Rhipicephalus capensis, Rhipicephalus exophthalmos, Rhipicephalus follis, Rhipicephalus gertrudae, Rhipicephalus lounsburyi, Rhipicephalus lunulatus, Rhipicephalus pravus group and Rhipicephalus simus, were also collected.
显示更多 [+] 显示较少 [-]<i>Culicoides</i> biting midges at the National Zoological Gardens of South Africa : research communication 全文
2007
K. Labuschagne | L.J. Gerber | I. Espie | S. Carpenter
Culicoides biting midges (Diptera: Ceratopogonidae) are responsible for the transmission of a large number of pathogens to livestock and wild animals. In this study the presence of the genus, using light traps based at four different sites within the National Zoological Gardens of South Africa, was investigated during 2002-2004. In total, 37 species were recorded, including large numbers of Culicoides imicola Kieffer, 1913, which is responsible for the transmission of economically important arboviruses in South Africa, Europe, Middle and Far East. These results are discussed with reference to the wider Culicoides fauna in the Onderstepoort area of South Africa, their vector competence as well as biosecurity at the National Zoological Gardens.
显示更多 [+] 显示较少 [-]Intramammary antibiotics in dairy goats : withdrawal periods of three intramammary antibiotics compared to recommended withdrawal periods for cows 全文
2007
J. Karzis | E.F. Donkin | I.M. Petzer
Intramammary antibiotics are registered and tested for use in dairy cattle. This study investigated withdrawal periods of three intramammary antibiotics (Curaclox LC [Norbrook Pharmacia AH]), Spectrazol Milking Cow (Schering-Plough Animal Health) and Rilexine 200 LC (Logos Agvet [Virbac]) in dairy goats and compared them to withdrawal periods recommended for use in cattle. Three trials were carried out in two different herds. The withdrawal periods for Curaclox LC in eight relatively low producing Saanen goats were 74.3 h (+ 19.21) measured by Thermo-Resistant Inhibitory Substances (TRIS), 90.0 h (+ 16.97) measured by colour dye, 99.4 h (+ 9.07) for cloxacillin measured by Parallux Beta Lactam Assay test (IDEXX distributors), and 92.6 h (+ 11.41) for ampicillin measured by Parallux. The withdrawal period for Curaclox LC recommended for use in cattle (72 h) was significantly shorter than the withdrawal periods as measured by colour dye (P < 0.001), Parallux testing for cloxacillin (P < 0.001) and ampicillin (P = 0.003). There was a significant difference in withdrawal periods as measured by TRIS (P = 0.009) and colour dye (P = 0.036). The mean withdrawal periods measured on 12 relatively high producing Saanen and Saanen-Toggenburg crossbreed dairy goats measured by TRIS, colour dye and Parallux for ampicillin and cloxacillin were, however, shorter at 42.0 h (+ 7.077), 64.5 h (+ 60.26), 77.3 h (+ 13.56) and 70.7 h (+ 12.65), respectively. These withdrawal periods for Curaclox LC were significantly longer than the withdrawal periods recommended for cattle as measured by TRIS (P < 0.001) and colour dye (P < 0.001). The combined withdrawal periods for Curaclox LC in the two trials as measured by TRIS, colour dye, Parallux testing for Cloxacillin and Ampicillin were 58.64h (+ 24.31), 75.8 h (+ 17.70), 87.0 h (+ 16.10) and 80.3 h (+ 16.23), respectively. The withdrawal period, when data of the two trials were combined, measured by TRIS (P < 0.001) was significantly longer than the withdrawal period recommended for use in cattle. The mean withdrawal period as measured by TRIS for Spectrazol Milking Cow for seven relatively low producing Saanen dairy goats was 95.3 h (+ 17.23). This was significantly (P < 0.001) longer than the withdrawal period recommended for use in cattle (60 h) for Spectrazol Milking Cow. The mean withdrawal period as measured by TRIS for Rilexine 200 LC for 20 relatively high producing Saanen and Saanen-Toggenburg crossbreed dairy goats was 36.9 h (+ 9.943) and was significantly (P < 0.001) shorter than the withdrawal period as recommended for use in cattle (96 h). There were also significant differences in all the one-sample t-tests between withdrawal periods for goats and recommended withdrawal periods for cattle without the 24 h safety margin.
显示更多 [+] 显示较少 [-]Red blood cell volume as a predictor of fatal reactions in cattle infected with <i>Theileria parva</i> Katete 全文
2007
P. Fandamu | T. Marcotty | J.R.A. Brandt | L. Duchateau | N. Speybroeck | T.T. Dolan | D. Berkvens
A comparison of mean corpuscular volume (MCV) and packed cell volume (PCV) was made between cattle undergoing lethal and non-lethal reactions following experimental infections with the apicomplexan protozoa, Theileria parva Katete. This work confirmed that anaemia occurs in infected animals. However, the fall in PCV was steeper in lethal reactions compared to non-lethal reactions. Our results show that animals with initially lower MCV values are more prone to fatal reaction, despite having normal PCV profiles. The study also found that small red blood cells are more likely to be infected with T. parva. These findings suggest that animals with a higher proportion of small red blood cells in circulation will be more likely to succumb to T. parva infections. The potential for using MCV as a predictor of the outcome of infection challenge is discussed.
显示更多 [+] 显示较少 [-]Goats as alternative hosts of cattle ticks 全文
2007
N. Nyangiwe | I.G. Horak
The objective of this study was to compare the presence on goats and cattle of adult ticks that usually infest cattle. To this end ticks collected from sets of five goats were compared with those collected from sets of five cattle at 72 communal dip-tanks in the eastern region of the Eastern Cape Province. Amblyomma hebraeum was present on goats at 25 and on cattle at 39 dip-tanks, and a total of 61 goats and 138 cattle were infested. Adult Rhipicephalus (Boophilus) microplus was present on goats at 48 and on cattle at 69 dip-tanks, and a total of 113 goats and 242 cattle were infested. The lengths of 84 of 148 female R. (Boophilus) microplus collected from the goats exceeded 5 mm or more, indicating that they could successfully engorge on these animals. The differences between the proportions of dip-tanks at which A. hebraeum or R. (Boophilus) microplus was present on goats and cattle and also between the proportions of goats and cattle that were infested were significant (Chi square test, P < 0.01). Adult Rhipicephalus appendiculatus was present on goats at 70 and on cattle at 67 dip-tanks, and a total of 296 goats and 271 cattle were infested. The proportion of dip-tanks at which cattle were infested did not differ significantly from the proportion of tanks at which goats were infested (Fischer's exact probability test, P = 0.44), but the proportion of infested cattle was significantly lower than the proportion of infested goats (Chi-square test, P < 0.05). Adult Rhipicephalus evertsi evertsi was present on goats and cattle at all 72 sampling localities, and a total of 334 goats and 316 cattle were infested. The proportion of infested cattle was significantly lower than the proportion of infested goats (Chi-square test, P < 0.05). These results underscore the necessity of including goats in any tick control programme designed for cattle at the same locality.
显示更多 [+] 显示较少 [-]Age prevalence of trypanosomal infections in female <i>Glossina morsitans morsitans</i> (Diptera : Glossinidae) on the plateau area of eastern Zambia 全文
2007
C. Kubi | M. Billiouw | P. Van den Bossche
Trypanosomal infections in female Glossina morsitans morsitans were investigated in an area in the Eastern Province of Zambia between 1992 and 1994. A total of 4 416 flies were captured, aged using the ovarian ageing method and screened for trypanosomal infections in both the mouthparts, salivary glands and the midgut. Congolense-type infections were identified in 4.8 % of the flies. Vivax-type and immature infections were identified in 1.8 % and 6.8 % of the flies, respectively. The prevalence of con golense-type, vivax-type and immature infections increased with age. For vivax-type infections the age-prevalence relationship could be described by a model assuming a constant per capita rate of infection. For congolense-type and midgut infections, a polynomial term was added to the model significantly improving the fit. The per capita at which flies become infected was significantly higher for immature compared to mature infections. Observations strongly suggest that tsetse acquire new midgut infections at any age and that maturation of these infections is not limited to those obtained during the first blood meal.
显示更多 [+] 显示较少 [-]Ticks (Acari: Ixodidae) collected from animals in three western, semi-arid nature reserves in South Africa : research communication 全文
2007
H. Golezardy | I.G. Horak
The objective of this study was to make an inventory of the ixodid tick species infesting wild animals in three western, semi-arid nature reserves in South Africa. To this end 22 animals in the Kgalagadi Transfrontier Park, 10 in the West Coast National Park and 16 in the Karoo National Park were examined. Fourteen tick species were recovered, of which Hyalomma truncatum, Rhipicephalus exoph thalmos and Rhipicephalus glabroscutatum were each present in two reserves and the remainder only in one. The distributions of two of the 14 tick species recovered, namely Rhipicephalus capensis and Rhipicephalus neumanni, are virtually confined to the western semi-arid regions of southern Africa. Hyalomma truncatum, R. capensis and R. glabroscutatum were the most numerous of the ticks recovered, and eland, Taurotragus oryx, were the most heavily infested with the former two species and gemsbok, Oryx gazella, and mountain reedbuck, Redunca fulvorufula, with R. glabroscutatum.
显示更多 [+] 显示较少 [-]Establishment of a statistically reliable sampling method and size for serological surveillance of classical swine fever (CSF) in Korea
2007
Yoon, H.C. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Nam, H.M. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Park, C.K. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Kim, B.H. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Park, J.Y. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Song, J.Y. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Hyeon, B.H. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Wee, S.H. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea), E-mail: [email protected]
To establish a statistically reliable sampling strategy for serological surveillance of classical swine fever (CSF) in Korea, antibody test data from CSF surveillance conducted during year 2005 were analyzed. The most appropriate sampling method was determined to be stratified multi-stage random sampling strategy, in which the primary sampling unit is a pig farm and the secondary are the pigs by the strata of breeders and finishers in the selected farm. The optimum sample size was 5 to 19 including 1 to 2 breeders according to the number of pigs in the farm.
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