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1.
Shima E. Abdalla Akebe L.K. Abia Daniel G. Amoako Keith Perrett Linda A. Bester Sabiha Y. Essack 《The Onderstepoort journal of veterinary research》2022,89(1)
BackgroundDiarrheagenic E. coli (DEC) strains are a major cause of diarrheal diseases in both developed and developing countries. Healthy asymptomatic animals may be reservoirs of zoonotic DEC, which may enter the food chain via the weak points in hygiene practices.AimWe investigated the prevalence of DEC along the pig production continuum from farm-to-fork.MethodsA total of 417 samples were collected from specific points along the pig production system, that is, farm, transport, abattoir and food. E. coli was isolated and enumerated using Colilert. Ten isolates from each Quanti-tray were selected randomly and phenotypically identified using eosin methylene blue agar selective media. Real-time polymerase chain reaction (PCR) was used to confirm the species and to classify them into the various diarrheagenic pathotypes. Antimicrobial susceptibility was determined against a panel of 20 antibiotics using the Kirby-Bauer disk diffusion method and EUCAST guideline.ResultsThe final sample size consisted of 1044 isolates, of which 45.40% (474/1044) were DEC and 73% (762/1044) were multidrug-resistant. Enteroinvasive E. coli (EIEC) was the most predominant DEC at all the sampling sites.ConclusionThe presence of DEC in food animal production environments and food of animal origin could serve as reservoirs for transmitting these bacteria to humans, especially in occupationally exposed workers and via food. Adherence to good hygienic practices along the pig production continuum is essential for mitigating the risk of transmission and infection, and ensuring food safety. 相似文献
2.
M.N. Bester 《African Zoology》2013,48(4):229-234
Population size of Arctocephalus tropicalis on Gough Island was determined by direct censuses of parts of the coast during the summers of 1974 – 1976 and 1977 – 1978 and correction factors for undercounting and seasonal cycles were applied. Present population size is approximately 200 000, giving an intrinsic rate of increase of 15,9% per year since 1955/56, but is now approaching the negative acceleration phase in population growth as a result of optimal breeding space becoming limited. An extension of breeding colony sites has also occurred since 1955. 相似文献
3.
In a randomised, placebo-controlled clinical trial, anaesthesia was induced with propofol (4 mg/kg) after intravenous premedication with or without midazolam (0.1 mg/kg), in a group of 8 dogs scheduled for ovariohysterectomy. Midazolam administration induced acute behavioural changes, and increased reflex suppression after propofol induction. Compared to the control group, the dose required to obtain loss of the pedal reflex was significantly reduced by 37%, and the end-tidal isoflurane concentration during maintenance, reduced by 23%. 相似文献
4.
Glutathione (GSH) at concentrations of 0.0 (control), 0.5, 1.0, 2.0 and 3.0 mM was added to chilled bull semen to determine its effects on the keeping quality of semen used for artificial insemination (AI). The semen was preserved with egg yolk citrate extender. All samples were stored at 4-8 degrees C for 5 days. Sperm motility and proportion of abnormal acrosome were assessed daily. Sperm motility was significantly (p < 0.01) higher in the semen treated with 0.5 mM glutathione than in untreated semen on each day. The optimum sperm motility (>or=50%) for AI was retained significantly (p < 0.01) for 3 days in 0.0, 0.5, 1.0 and 2.0 mM glutathione treated semen, whereas in 0.3 mM glutathione-treated semen, sperm motility was 46.8% for 3 days. Acrosomal damage was significantly (p < 0.01) reduced after addition of 0.5 mM GSH in the preserved semen. Bull semen can be preserved in chilled condition for 5 days with 0.5 mM GSH with sperm motility above 40% and 12% acrosome abnormality. 相似文献
5.
KC Silva‐Santos CR Ferreira GMG Santos MN Eberlin LS Siloto CO Rosa TN Marcantonio MM Seneda 《Reproduction in domestic animals》2014,49(5):711-718
The aim of the present study was to compare the lipid profile in oocytes of indicus and 1/2 indicus × taurus cows with high and low antral follicle count (AFC)/oocyte yields. After an OPU procedure (D0), antral follicles ≥3 mm were counted by ultrasonography (D4, 19, 34, 49, 64), and cows were assigned to groups with either high AFC (≥30 follicles; indicus, NH group; 1/2 indicus × taurus, AH group) or low AFC (≤15 antral follicles; indicus, NL group; 1/2 indicus × taurus, AL group). The lipid profiles of the oocytes were determined by MALDI‐MS. For GI, GII and GIII oocytes, the indicus samples tend to cluster separately from the 1/2 indicus × taurus samples. The lipid species [PC (P‐38:5) + H]+ and/or [PC (P‐36:2) + Na]+, [PC (38:2) + H]+, [PC (38:5) + Na]+ and [TAG (60:8) + NH4]+ were more abundant in indicus (NH and NL groups) than 1/2 indicus × taurus. The higher lipid content in the indicus oocytes likely reflects differences in the rate of lipid metabolism and may contribute to oocyte competence and embryo development. 相似文献
6.
G F Stegmann BVSc MmedVet DipECVA L Bester BVSc 《Veterinary anaesthesia and analgesia》2001,28(1):49-55
Objective To examine the effect of dose and route of administration on the sedative‐hypnotic effects of midazolam. Design Prospective randomized controlled study Animals Six indigenous, African bred goats. Methods Pilot studies indicated that the optimum dose of midazolam for producing sedation was 0.6 mg kg?1 for intramuscular (IM) injection, while the optimum intravenous (IV) doses causing hypnosis without, and with loss of palpebral reflexes were 0.6 mg kg?1 and 1.2 mg kg?1, respectively. These doses and routes of administration were compared with a saline placebo in a randomized block design in the main experiment, and the sedative‐hypnotic effects evaluated according to pre‐determined scales. Results Intramuscular midazolam produced sedation with or without sternal recumbency in all animals with the peak effect occurring 20 minutes after administration. The scores for IM sedation with midazolam were significantly different (p < 0.05) from placebo. Intravenous midazolam at 0.6 mg kg?1 resulted in hypnosis, and at 1.2 mg kg?1 increased reflex suppression was observed. The maximum scores for hypnosis at both doses were obtained 5 minutes after IV injection. The mean (± SD) duration of lateral recumbency was 10.8 (± 3.8) minutes after IV midazolam (0.6 mg kg?1) compared to 20 (± 5.2) minutes after midazolam at 1.2 mg kg?1. Compared to baseline, the heart rate increased significantly (p < 0.05) after high dose IV midazolam. Conclusion Intramuscular midazolam (0.6 mg kg?1) produced maximum sedation 20 minutes after injection. Intravenous injection produced maximum hypnosis within 5 minutes. Increasing the IV dose from 0.6 to 1.2 mg kg?1 resulted in increased reflex suppression and duration of hypnosis. Clinical relevance For a profound effect with rapid onset midazolam should be given IV in doses between 0.6 and 1.2 mg kg?1. 相似文献
7.
Breeding success of Pterodroma macroptera, Procellaria aequinoctialis and Pachyptila vittata salvini in three cat-free and three control areas were used to evaluate the effects of cat Felis catus predation on the avifauna of Marion Island. Breeding success of all three species was significantly higher in the combined cat-free areas than in the combined control areas. However, breeding success in one cat-free area failed to show a significant difference from its particular control area, probably as a result of higher skua (Catharacta antarctica) predation inside the cat-free area. Chicks of P. macroptera and P. aequinoctialis were especially vulnerable to cat predation, since cats can enter their nesting burrows. P. macroptera was seriously affected by cat predation because it is the most abundant of only two winter-breeding petrels. Significant changes in the number of nest visits by these petrels during their breeding season followed hatching dates, which in turn were concomitant with, or were followed by significant differences in the combined breeding success between the cat-free and control areas. The cat-free areas show that an elimination of cat predation would still favour the recovery of the petrel population. 相似文献
8.
The diurnal activity patterns of sub-Antarctic fur seals, Arctocephalus tropicalis, were observed at a non- breeding colony site at Gough Island (40°20′S, 9°54′W) during summer. Time budgets of adult males were also studied at idle and breeding colony sites, Levels of activity were highest during the early morning and late afternoon. High ambient temperatures depressed the interaction rate on the dry hauling ground, but activity increased as a result of the movement of heat-stressed seals to and from the sea where favourable conditions for heat loss exist. The fur seals were largely inactive, in particular adult males which spent 93,2% of the time inactive in breeding colonies and 97,9% of Ihe time inactive at idle colony beaches. The daily change in numbers ashore, the relative contribution of the different age and sex classes, their location and distribution on site, and the prevailing weather conditions influence the pattern of interaction and allocation of time to the various activities in A. tropicalis. The predominance of inactivity is considered to be a behavioural thermoregulatory response to limit endogenous heat production as is energy conservation. Both views translate into improved tenure for territorial males, in particular those without access to water for cooling during the breeding season. 相似文献
9.
Steenkamp G Ferguson WH Boy SC Ferreira SM Bester MN 《Journal of the South African Veterinary Association》2008,79(1):25-30
Captive and wild African elephants frequently suffer tusk fractures. Several institutions shorten the tusks of captive elephants to reduce fractures and injury as a result of behaviour within enclosures. Fracturing or coronal amputations that expose pulp lead to pain for the elephant. Estimating coronal pulp lengths may thus help to minimise the risk of pulp exposure during amputations. We aimed to determine the length of the pulp beyond the lip margin from an external tusk characteristic. Tusks collected from elephants in Namibia and the Kruger National Park had similar morphological relationships. This statistical property allowed us to correct for missing data in our data sets. Pulp volume and pulp length correlated with tusk circumference at the lip. Even so, the circumference at the lip could not predict the length of the pulp in the crown external to the lip. Our findings suggest that tusks, irrespective of sex or age, amputated further than 300 mm from the lip should not expose pulp. 相似文献
10.
Exogenous paraoxonase‐1 during oocyte maturation improves bovine embryo development in vitro 
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下载免费PDF全文 JAA Rincón EM Madeira FT Campos B Mion JF Silva VA Absalón‐Medina WR Butler MN Corrêa LMC Pegoraro A Schneider 《Reproduction in domestic animals》2016,51(5):827-830
Paraoxonase‐1 (PON1) is an enzyme found in serum and follicular fluid that protects cell membrane and circulating lipids against oxidative damage. The aims of this study were to measure the direct effects of recombinant PON1 (rPON1) on bovine oocyte maturation at the molecular level (gene expression) and to measure the carry‐over effects of PON1 on pre‐implantation embryo development in vitro. COCs were submitted to IVM with the addition of 0.0, 0.02, 0.04 and 0.08 mg ml?1 of rPON1, corresponding to an average PON1 arylesterase enzyme activity of 2.2 ± 0.4, 15.5 ± 1.5, 30.2 ± 3.0 and 57.9 ± 5.0 U ml?1, respectively. The results indicated that addition of rPON1 during IVM improved embryo development in a dose‐dependent manner as D7 embryo development was 22.2%, 29.4%, 32.2% and 37.0% for the treatment groups, respectively (p = 0.02). In conclusion, addition of PON1 enzyme during IVM exerted dose‐related positive effects on embryo development rates to blastocysts. 相似文献