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In vitro anti-tick properties of the essential oil of Tagetes minuta L. (Asteraceae) on Hyalomma rufipes (Acari: Ixodidae)
2012
Felix Nchu | Solomon R. Magano | Jacobus N. Eloff
In this study we examined the anti-tick properties of the essential oil of Tagetes minuta L. (Asteraceae: Asterales) against Hyalomma rufipes ticks. We obtained the essential oil of T. minuta by hydro-distillation of a combination of fresh flowers, leaves and soft stems, and analysed these by using gas chromatography (GC) and gas chromatography-linked mass spectrometry (GC-MS). The oil had a high percentage of monoterpenes and the major compounds identified were cis-ocimene (28.5%), beta-ocimene (16.83%) and 3-methyl-2-(2-methyl-2-butenyl)-furan (11.94%). Hyalomma rufipes adults displayed a significant (P < 0.05) dose repellent response to the essential oil of T. minuta. Probit analysis indicated a repellent EC50 of T. minuta essential oil for male ticks to be 0.072 mL/mL (CI 0.053 mL/mL to 0.086 mL/mL) and 0.070 mL/mL (CI 0.052 mL/mL to 0.084 mL/mL) for female ticks. There were no significant differences in repellent responses between male and female ticks. The oil also significantly (P < 0.05) delayed moulting of 60% of H. rufipes engorged nymphs. These results suggest that T. minuta may be a potential source of anti-tick agents.
Afficher plus [+] Moins [-]α-SMA and Ki-67 Immunohistochemistry as Indicators for the Fibrotic Remodeling Process in the Liver of Dogs
2012
S. Neumann | F.J. Kaup
Liver cirrhosis is a fatal end-stage of various chronic liver diseases. It develops from persistent liver cell necrosis with resulting fibrosis. Because liver cirrhosis is an irreversible process it is important to recognize the reversible fibrotic stages of the disease. Different markers and staining are currently used to detect fibrosis. Besides plasma markers, some tissue markers are currently being used for this purpose. In this study, we investigated the expression of two immunohistochemical markers (Ki-67, α-SMA) in liver diseases with and without fibrosis in dogs and compared their expression with the degree of tissue fibrosis, assessed by Masson trichrome staining. In all the stages of fibrosis, Ki-67 and α-SMA was expressed in the liver tissue. There was no significant difference between Masson trichrome staining which is “gold standard” and expression of Ki-67 or α-smooth muscle actin (SMA). We concluded that Ki-67 and α-SMA can be potentially used as markers for the fibrotic remodeling of the liver.
Afficher plus [+] Moins [-]Immunohistochemical Localization of Progesterone Receptors in the Non-pregnant One-humped Camel Uterus
2012
Mahmoud M. M. Abd-Elnaeim | K. A. Al-kheraije
The current study aimed to localize immunohistochemically the cellular progesterone receptors in the non-pregnant one-humped camel uterus. Uterine tissue specimens from 10 she-camels during estrous were collected from local slaughterhouses and prepared for indirect immunoperoxidase staining using primary antibody for human progesterone receptor PR (clone 10A9). Nuclear signals for progesterone receptors were clearly observed in the uterine surface epithelium, glandular epithelium, myometrium, uterine stroma and in walls of some large blood vessels. The staining intensity was variable at different uterine tissue regions. Strong signals were demonstrated in the superficial gland zone, in the connective tissue stroma and in the myometrium. However, Nuclear signals of moderate intensity were noticed in the surface epithelium, deep gland zones and in the walls of the uterine arteries. No cytoplasmic signals could be detected. The current study concluded that nuclear signals for progesterone receptors were found in uterine surface epithelium, uterine glands, myometrium, uterine blood vessels and stroma.
Afficher plus [+] Moins [-]A questionnaire survey of poultry layer farmers in Khartoum State, Sudan, to study their antimicrobial awareness and usage patterns
2012
Mohamed M. Sirdar | Jackie Picard | Shahn Bisschop | Bruce Gummow
An initial census of layer farms in Khartoum State, Sudan, was carried out in late 2007 and early 2008 and found that there were 252 layer farms with a total population of 2 221 800 birds. This paper reports the findings of the census. Based on this information, a structured questionnaire survey of 92 farms was then conducted in the state in April 2008 to collect data on antibiotic usage, demographic data and public health awareness. Ninety-eight per cent of participating farms comprised open-sided houses. It was found that 49% of the farms surveyed were on antibiotic treatment when the survey was conducted, whilst 59% of the farms had used antibiotics within the last 3 months. The study found that farmers and producers had a lack of knowledge about antimicrobial residues, their withdrawal periods and the risk posed by the consumption of these residues. The study also concluded that traditional farming systems in Sudan relied heavily on antimicrobial medication to control disease and almost half of the farms surveyed were treating their flocks with antimicrobials. In addition to this, there was a lack of disease control programmes which probably resulted in a massive use of antibiotics to control endemic diseases. This was further compounded by the absence of governmental supervision and control on the use of drugs.
Afficher plus [+] Moins [-]Prevalence of Multidrug Resistant Bacillus cereus in Foods and Human Stool Samples in and Around Pantnagar, Uttrakhand
2012
Anita Tewari | S.P. Singh | Rashmi Singh
.A total number of 63 samples out of 505 samples were found to be positive for Bacillus cereus. The positive samples comprised of 29 samples of human stool, 10 of milk, 23 of meat and meat products origin. These positive isolates were tested against 13 different commonly used antibiotics by the disc diffusion method. Antibiogram pattern of these 63 isolates indicated multidrug resistance. B. cereus isolates showed a high rate of resistance to Carbenicillin, Kanamycin and Ampicillin and intermediate frequency of resistance to Amoxicillin and Cephalothin. All the isolates irrespective of their source were resistant to Bacitracin and Penicillin G and sensitive to Aminoglycosides (Gentamycin, Neomycin and Streptomycin) and Chloramphenicol. However, variable resistance patterns were also recorded in B. cereus isolates obtained from different origin, which is suggestive of source-associated resistance. It can be inferred from the above study that presence of multidrug resistant B. cereus in animal-origin food and environment in such high proportion is of public health significance.
Afficher plus [+] Moins [-]Prevalence of bovine trypanosomosis and its vectors in two districts of East Wollega Zone, Ethiopia
2012
Wagari Tafese | Achenef Melaku | Tewodros Fentahun
Trypanosomosis is a parasitic disease that causes serious economic losses in livestock, especially in sub-Saharan countries. This study was conducted from October 2010 to March 2011 in the Diga and Sasiga districts of the East Wollega zone in western Ethiopia to determine the prevalence of bovine trypanosomosis and its vectors. A total of 386 blood samples were collected from randomly selected animals. Packed cell volume (PCV) was determined and samples were examined for the presence of trypanosomes using the buffy coat technique. Out of 386 blood samples, 8.55% tested positive for trypanosomes. The majority of the infections were caused by Trypanosoma congolense (72.73%), followed by Trypanosoma vivax (27.27%). There were no statistically significant differences (p > 0.05) between districts, altitudes, sexes and ages, but the prevalence was significantly higher (p < 0.05) in cattle which were in poor body condition. The mean PCV value of infected animals (21.45 ± 3.62 s.d.) was significantly lower (p < 0.05) than that of non-infected animals (26.60 ± 4.60 s.d.). A total of 1151 flies were caught by deploying 21 monoconical shaped traps. Of these flies, 822 (71.42%) were Glossina, whilst the remaining flies were either Stomoxys (17.20%) or Tabanus (11.38%). The overall apparent densities of tsetse and biting flies were 1.45 and 0.58 flies per trap per day, respectively. In conclusion, this study confirmed that trypanosomes and their vectors are prevalent and still pose a threat to cattle production in the area. Therefore, proper strategies have to be designed and implemented to minimise their effect on livestock production.
Afficher plus [+] Moins [-]Safety and Tissue Residue Determination of Gatifloxacin in Broiler Chicken
2012
S.S. Devada | U.D. Walunj | A.J. Patil | J.H. Patel | S.K. Bhavsar | A.M. Thaker
Gatifloxacin is a fluoroquinolone having broad-spectrum activity and good antibacterial activity at low plasma/tissue concentration. The present study was designed to investigate safety of gatifloxacin (10 mg/kg body weight) after repeated oral administration at 12 hours interval for 14 days in broiler chickens and to determine tissue concentration of the drug following oral administration (10 mg/kg body weight) for 5 days. Repeated oral administration of gatifloxacin in broiler chickens was found safe based on evaluation of hematological (Hb, PCV and TLC), biochemical (AST, ALT, ALP, LDH, Serum uric acid, Serum Creatinine, Blood glucose and Total bilirubin) and histopathology of liver, kidney, heart and joint cartilage. Drug concentration in tissue was determined using High Performance Liquid Chromatography (HPLC). The concentration of gatifloxacin was found 0.75 ± 0.04 µg/g after fourth dose and 0.22 ± 0.07 µg/g after tenth dose respectively in liver, whereas in skeletal muscles the concentration of gatifloxacin was below the limit of quantification after fourth dose and after tenth dose gatifloxacin was not detected.
Afficher plus [+] Moins [-]Comparing effects of freezing at -196 °C and -20 °C on the viability of mastitis pathogens
2012
Inge-Marie Petzer | Joanne Karzis | Theodorus J. van der Schans | Johanna C. Watermeyer | Norman Mitchell-Innes | Stephanie Eloff | Geoffrey T. Fosgate
The aim of this study was to compare the effects of cryopreservation at approximately -196 °C in liquid nitrogen (N) and freezing at approximately -20 °C in a freezer, on the viability and survival of eight different mastitogenic bacteria inoculated in milk. Bacteria were frozen at approximately -20 °C in a freezer and cryopreserved at approximately -196 °C in liquid nitrogen. An effective preservation method was needed for follow-up samples from cows identified in the South African National Milk Recording Scheme (NMRS) with somatic cell counts above 250 000 cells/mL milk. The organisation responsible for sample collection of the NMRS milk samples also provides producers with liquid nitrogen for their semen flasks at the collection sites. This existing mode of storage and transport could therefore be utilised.Ten samples of each organism were thawed and cultured bi-weekly until week 18 for both temperature treatments. An additional sampling was performed at week 30 for samples frozen at approximately -20 °C. Freezing and cryopreservation did not impair subsequent isolation of Streptococcus dysgalactiae, Streptococcus uberis, Enterococcus faecalis, Staphylococcus aureus (STH) (phage type lytic group III) or Sta. aureus (STA) (phage typed, other than lytic group III). Survival was indicated by the isolation of bacteria from samples, and viability by the strength of growth of the bacteria isolated. The survival of Streptococcus agalactiae decreased after week 12 and Escherichia coli after week 16 of freezing, but both organisms survived under cryogenic preservation until week 18. Coagulase-negative staphylococci survived until week 18 for both freezing and cryogenic preservation.Both storage methods could thus contribute to the improvement of a pro-active approach towards udder health management in South African dairy herds.
Afficher plus [+] Moins [-]Seroprevalence of leptospirosis in dogs in urban Harare and selected rural communities in Zimbabwe
2012
Solomon Dhliwayo | Gift Matope | Lisa Marabini | Keith Dutlow | Davis M. Pfukenyi
A cross-sectional study was conducted to investigate seroprevalence of canine leptospirosis in urban Harare and five selected rural communities in Zimbabwe and to assess public awareness of the disease. Sera from randomly selected dogs were tested for antibodies to the serovars Canicola, Grippotyphosa, Icterohaemorrhagiae and Pomona of <em>Leptospira interrogans</em> using an enzyme-linked immunosorbent assay. Clinical chemistry was performed on all seropositive and selected seronegative sera to screen for hepatic and renal insufficiency. A questionnaire- based survey was conducted in Harare to assess dog owners’ awareness of leptospirosis and other zoonoses. Overall, 15.6% of sera samples tested (39 out of 250; 95% confidence interval [CI]: 11.0% – 20.2%) were positive for leptospiral antibodies. A significantly higher (<em>p</em> < 0.05) seroprevalence was recorded in urban dogs than in rural dogs (25% vs. 11.2%). No significant difference in seroprevalence was observed amongst dogs from different rural communities or between sexes of dogs. There was a significant association between seropositivity and hepatic and/or renal insufficiency (<em>p</em> < 0.01), with dogs having hepatic and/or renal insufficiency being approximately twice as likely to be seropositive (relative risk = 1.96; 95% CI: 1.3–3.0). Of the dog owners, 78.8% (119/151) were aware of zoonoses. Except for rabies (92.4%), awareness of leptospirosis (5.0%) and other zoonoses amongst these owners was low. This study showed that leptospirosis was present and represented a risk to dogs from urban Harare and the selected rural communities in Zimbabwe. Availing training programmes for dog owners would be beneficial in improving disease control and reducing the public health risk of pet zoonoses.
Afficher plus [+] Moins [-]Ticks (Acari: Ixodidae) infesting cattle and African buffaloes in the Tsavo conservation area, Kenya
2012
Edward K. Kariuki | Barend L. Penzhorn | Ivan G. Horak
Several ixodid tick species are shared between domestic cattle and African buffaloes (<em>Syncerus caffer</em>). So too, are a number of tick-borne diseases. The aim of the study was to compare the species composition of ticks that infest cattle and buffaloes utilising the same habitat within the Tsavo Conservation Area, Kenya. To this end, 25 cattle and 62 buffaloes were each opportunistically sampled for ticks on a single occasion in February 2010. Eight species, namely <em>Amblyomma gemma</em>, <em>Amblyomma lepidum</em>, <em>Hyalomma albiparmatum</em>, <em>Hyalomma rufipes</em>, <em>Hyalomma truncatum</em>, <em>Rhipicephalus evertsi evertsi</em>, <em>Rhipicephalus pravus</em> and <em>Rhipicephalus pulchellus</em> infested both cattle and buffaloes. Three species, <em>Rhipicephalus</em> (<em>Boophilus</em>) sp., <em>Rhipicephalus kochi</em>, and <em>Rhipicephalus muehlensi</em> were collected only from cattle, and three species,<em> Hyalomma impeltatum</em>, <em>Rhipicephalus humeralis</em> and<em> Rhipicephalus praetextatus</em> were present only on buffaloes. The attachment sites of the various tick species were also recorded. New locality records for <em>H. impeltatum</em> and <em>H. truncatum</em> and the first confirmed locality record for <em>Rhipicephalus praetextatus sensu stricto</em> in Kenya were documented.
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