خيارات البحث
النتائج 121 - 130 من 596
Intramammary antibiotic withdrawal periods for dairy goats compared to those for dairy cattle النص الكامل
2008
Petzer, I.M. | Donkin, E.F. | Du Preez, E. | Karzis, J. | Van der Schans, T.J. | Watermeyer, J.C. | Van Reenen, R.
This study investigated the withdrawal periods (WP) of two intramammary antibiotics Cloxamast LC (Intervet SA) and Spectrazol Milking Cow (Schering-Plough Animal Health) in dairy goats and compared them to those recommended for use in cattle. The WP for Cloxamast LC, measured by the Thermo Resistant Inhibitory Substances (TRIS) test, was 60 h in composite samples, 56 h in udder half samples, and the dye was visible for up to 56 h. The WP was significantly shorter than the 72 h recommended WP for use in cattle. It was however significantly longer when the 24 h safety margin (48 h) was subtracted from the recommended WP for cattle. For Spectrazol Milking Cow the antibiotics could be detected by the TRIS test for 61 h in composite samples and 59 h in udder half samples. This did not differ significantly from the recommended 60 h WP for cattle. However, it was significantly longer than that recommended for use in cattle without the 24 h safety margin. There was no significant difference in WP between infected and non-infected udder halves, while there was a weak positive correlation between WP and stage of lactation (R2 = 0.253). There was a moderate positive correlation (R2 = 0.583) between the TRIS test and the presence of dye in milk in udder half samples and between WP in both udder half and composite milk samples (R2 = 0.456). Weak to moderate positive correlations were present between milk yield and the WP in both udder half (R2 = 0.414) and composite (R2 = 0.262) milk samples. Significant differences (P 0.001) were also observed between the milk yield of udder halves with and without palpable udder damage and between samples that tested TRIS positive and negative on both composite (P = 0.008) and udder half samples (P 0.001). There was no significant difference between the milk yield of samples with or without dye. There was a significant difference in milk yield between infected and non-infected udder halves (P = 0.054) and a weak negative correlation between milk yield and stage of lactation (R2 = -0.379).
اظهر المزيد [+] اقل [-]The prevalence and distribution of Argas walkerae (Acari: Argasidae) in the eastern region of the Eastern Cape Province, South Africa : research communications النص الكامل
2008
Nyangiwe, N. | Gummow, B. | Horak, I.G.
The prevalence and geographic distribution of the fowl tampan, Argas walkerae Kaiser Hoogstraal, 1969 was determined in the eastern region of the Eastern Cape Province, South Africa by inspecting two fowl houses in the vicinity of each of 72 randomly selected communal cattle dip-tanks. Tampans were collected from 102 (70.8 %) of the 144 fowl houses in the neighbourhood of 57 (79.2 %) of the 72 selected dip-tanks, and the localities of the collections were mapped. Argas walkerae was present in fowl houses from the warm coastal regions of the Indian Ocean in the south to the cold and mountainous Drakensberg in the north-east of the Province. Taking into account the probable sensitivity of the sampling method, it is estimated that A. walkerae is likely to be present in fowl houses belonging to between 74 and 84 % of communities making use of cattle dip-tanks in the eastern region of the Eastern Cape Province, and that when it is present, between 64 and 75 % of fowl houses will be infested. The geographic distribution of A. walkerae seemed to be more strongly associated with the presence of fowls and fowl houses containing raw or processed wood in their structure than with climate.
اظهر المزيد [+] اقل [-]Haemophilus paragallinarum haemagglutinin : role in adhesion, serotyping and pathogenicity النص الكامل
2008
Barnard, T.G. | Van Heerden, E. | Bragg, R.R. | Albertyn, J.
It is suggested that Haemophilus paragallinarum requires at least three haemagglutinins for adhesionduring infection. This paper reports the partial purification and characterization of the HA-L haemagglutininfrom H. paragallinarum strain 46-C3, a heat sensitive, trypsin sensitive haemagglutinin that hasbeen shown to be the serovar specific haemagglutinin in this organism. Using the pI and molecularmass obtained, it was shown that this protein shares similarities with other types of adhesins found in Gram-negative bacteria. The haemagglutination assay conditions were optimized at pH 7.5 at 37 C. It was also shown that activity is enhanced by the addition of Ca2+ and Mn2+ ions.
اظهر المزيد [+] اقل [-]Evaluation of larvicides in developing management guidelines for long-term control of pest blackflies (Diptera: Simuliidae) along the Orange River, South Africa النص الكامل
2008
Palmer, R.W. | Rivers-Moore, N.A.
In 2000 and 2001 Orange River levels were higher than normal: associated serious outbreaks of blackfly had a substantial detrimental impact on the local economy. The poor control was attributed to the suspected development of larval resistance to temephos. A long-term solution to blackfly control, through the identification of a suitable replacement to temephos for use during high flow conditions, was proposed. This study, however, failed to identify or register a suitable larvicide for use during high flow conditions. Although permethrin was highly effective against blackfly larvae, it was rejected because of its detrimental impacts on non-target fauna. Various formulations of locally produced dry Bacillus thuringiensis var. israelensis (B.t.i.) were tested, but these were ineffective against blackflies. The study also confirmed that resistance to temephos has developed among Simulium chutteri in the middle and lower Orange River. The feasibility of "reversing" the resistance to temephos through the use of the synergist piperonyl butoxide (PBO) was investigated, but the results were not favourable. Furthermore, PBO was highly toxic to blackflies and non-target organisms, and was not recommended for further testing. This means that B.t.i. currently remains the only symptomatic measure of treatment currently applied. Although resistance to B.t.i. has not been reported for blackflies elsewhere in South Africa, there is a need to remain vigilant and to implement an operational strategy that minimizes the risks of resistance developing.
اظهر المزيد [+] اقل [-]Cercariae developing in Lymnaea natalensis Krauss, 1848 collected in the vicinity of Pretoria, Gauteng Province, South Africa النص الكامل
2008
Moema, E.B.E. | King, P.H. | Baker, C.
Freshwater snails are known to serve as first intermediate hosts for various parasitic diseases such as schistosomosis and fasciolosis. Snails were collected on several occasions in the proximity of Pretoria, South Africa and their cercarial sheddings were studied. This article describes three different types of cercariae shed by the freshwater snail, Lymnaea natalensis, viz. a fork-tailed cercaria of a Trichobilharzia sp., an avian parasite belonging to the family Schistosomatidae, an echinostomatid cercaria of the family Echinostomatidae, also avian parasites and a xiphidiocercaria of the family Plagiorchiidae which parasitise avians and amphibians. The morphology of these cercariae was studied by light and scanning electron microscopy.
اظهر المزيد [+] اقل [-]Expression of galectin-3 in the testis and epididymis of mouse
2008
Kim, W.J. (Cheju National University, Jeju, Republic of Korea) | Kim, H.L. (Cheju National University, Jeju, Republic of Korea) | Joo, H.G. (Cheju National University, Jeju, Republic of Korea) | Shin, T.K. (Cheju National University, Jeju, Republic of Korea) | Lee, Y.D. (Korean Racing Authority, Jangsoo, Republic of Korea) | Kim, S.J. (Kyungpook National University, Daegu, Republic of Korea), E-mail: [email protected]
The testis and epididymis are important organs of the male reproductive system; the function is to produce, mature, transport, and store sperm. It is important to understand the localization and expression of specific proteins based for the studies of its physiological processes. In the study, we investigated the expression and distribution of galectin-3, one beta-galactoside-binding proteins, in the testis and epididymis of mouse using western blot and immunohistochemistry. Western blot analysis revealed that the expression of galectin-3, 29 kDa protein, was low in the testis. In the epididymis, high expression was detected in the body and tail part, but moderate expression in the head part. By immunohistochemical analysis, we found that positive localization of galectin-3 was detected in some myoid cells and Leydig cells in the testis, but few in the seminiferous tubules. In the epididymis, galectin-3 was intensely expressed in the epithelium of epididymis, especially in the epithelium of both body and tail epididymis. Collectively, these results suggest that galcetin-3 is constitutively expressed in the testis and epididymis of mouse with varying intensity, and the role of galectin-3 in the male reproductive organ may be involved in the specific function of its structures.
اظهر المزيد [+] اقل [-]Determination of eugenol in Eugenia caryophyllata by high-performance liquid chromatography with photodiode array detection and method validation
2008
Yun, H.J. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Yun, S.M. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Lee, M.H. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea), E-mail: [email protected] | Son, S.W. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea)
A method for the quantification of eugenol in the medicinal herb Clove was developed and validated. For preparation of sample solutions clove was dried at 60℃ for 2h and ground by mixer and extracted with 95% ethanol for shaking extraction. The elutes were analyzed by HPLC system included a reversed phase column, a isocratic mobile phase of 60% methanol and PDA detector set at 280 nm. Calibration graphs were linear with very good correlation coefficients(r² greater then 0.9999) from 0.0125~1 ㎍/ml. The limit of detection per sample injection (20 ㎕) was 0.81 ng/㎕ and limit of quantification was 2.47 ng/㎕. The method showed good intra-day precision (%RSD 0.08~0.27%) and inter-day precision (%RSD 0.32~1.19%).
اظهر المزيد [+] اقل [-]Evaluation of antitumor, hepatoprotective and antimutagenic potentials of Phellinus gilvus
2008
Kang, E.H. (Kyungpook National University, Daegu, Republic of Korea) | Kim, K.S. (Kyungpook National University, Daegu, Republic of Korea) | Park, S.C. (Kyungpook National University, Daegu, Republic of Korea), E-mail: [email protected]
This study was carried out to evaluate the antitumor, hepatoprotective and antimutagenic activities on hot water extract of Phellinus gilvus (PGE). Growth of tumor in mice that were orally given 0.25, 0.5, 1.0, 2.0 gㆍkg-¹ dose of PGE was inhibited in a dose-dependant manner (p less than 0.05). The hepatoprotective effect of PGE in the carbon tetrachloride (CCl₄)-intoxicated rats was studied. In CCl₄+PGE groups, PGE was orally administered with 100 mg/kg/day dose 7 days before the treatment of CCl₄. The serum activity of aspartate aminotransferase and alanine aminotransferase in CCl₄+PGE group were decreased at a rate of 59.6% and 54.1% compared with those in CCl₄ group, respectively (p less than 0.05). Also, total cholesterol and triglyceride in CCl₄+PGE group were significantly decreased at a rate of 90% and 73.6% compared with those in CCl₄ group (p less than 0.05). In the Ames test, we confirmed PGE doesn't have any activity as a mutant, and PGE showed inhibitory effect against mutagenesis induced by 2-amino fluride and sodium azide in Salmonella typhimurium TA98, TA100 and TA 1535 in a dose-dependent manner. From the above results, we may suggest that PGE might have useful as a material for functional food and/or animal pharmaceutics.
اظهر المزيد [+] اقل [-]Determination of amitraz by high-performance liquid chromatography with photodiode array detection and method validation
2008
Yun, H.J. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Yun, S.M. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Lee, M.H. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea), E-mail: [email protected] | Son, S.W. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea)
In veterinary medicine amitraz has been used as an insecticide to eliminates mites, lice, and ticks in dogs, cats, goats, swine and cattle. The objective of present study was to developed an analytical method using one-step extraction and determination of the amitraz in veterinary drugs by liquid chromatography (LC). The amitraz was analyzed by LC equipped with Waters XTerra RP18 (4.8×250 mm; 5 ㎛; Waters, USA) analytical column, using 75% acetonitrile (acetonitrile/D.W; 75/25) at 1.0 ml/min. The UV-VIS detection of amitraz was made at 290 nm. Calibration graphs were linear with very good correlation coefficients (r² greater than 0.9999) from 80~120 ㎍/ml. The limit of detection was 0.09 ㎍/ml and limit of quantification was 0.27 ㎍/ml. The method showed good intra-day precision (CV 0.05~0.09%) and inter-day precision (CV 0.06~0.18%).
اظهر المزيد [+] اقل [-]Analysis of polychlorinated dibenzo-p-dioxins and dibenzofurans to assure safety of imported meat
2008
Kim, M.K. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea), E-mail: [email protected] | Kim, D.G. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Kim, S.Y. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Choi, S.W. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Kwon, J.W. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Yun, S.J. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Song, S.O. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Chung, G.S. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea)
Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are ubiquitous and can contaminate the food chain. A study monitoring PCD/Fs in imported meat was conducted at the National Veterinary Research and Quarantine Service (NVRQS, Republic of Korea) in order to maintain food safety from the bioaccumulative PCDD/Fs. Seventeen PCDD/Fs with toxic equivalency factors (TEFs) established by World Health Organization (WHO, 1998) were analyzed in imported beef, pork, and chicken by high resolution gas chromatography/mass spectrometry (HR-GC/MS). Results of the monitoring for the last 5 years are presented. The levels of PCDD/Fs were similar to other studies except two unusually high concentrations in pork and beef. Excessive levels greater than the Korean provisional maximum residue limit of PCDD/Fs were found in a sample of pork imported from Chile and a sample of beef imported from U.S, and those products were rejected and returned. These was no obvious trend or differences with respect to time or origin of meat in this study.
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