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1.
AIM: To assess the benefit of inducing emesis in dogs that have ingested rodenticide bait containing brodifacoum (BDF), by determining the amount of BDF in bait recovered from the vomitus relative to the estimated amount consumed.

METHODS: Between 2014 and 2015 samples of vomitus from seven dogs that ingested rodenticide baits containing BDF were submitted by veterinarians in New Zealand. All seven dogs had been given apomorphine by the veterinarian and vomited within 1 hour of ingesting the bait. Some or all of the bait particles were retrieved from each sample and were analysed for concentrations of BDF using HPLC. Based on estimations of the mass of bait consumed, the concentration of BDF stated on the product label, and the estimated mass of bait in the vomitus of each dog, the amount of BDF in the vomited bait was calculated as a percentage of the amount ingested.

RESULTS: For five dogs an estimation of the mass of bait ingested was provided by the submitting veterinarian. For these dogs the estimated percentage of BDF in the bait retrieved from the vomitus was between 10–77%. All dogs were well after discharge but only one dog returned for further testing. This dog had a normal prothrombin time 3 days after ingestion.

CONCLUSIONS AND CLINICAL RELEVANCE: The induction of emesis within 1 hour of ingestion can be a useful tool in reducing the exposure of dogs to a toxic dose of BDF. The BDF was not fully absorbed within 1 hour of ingestion suggesting that the early induction of emesis can remove bait containing BDF before it can be fully absorbed.  相似文献   

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Maize (Zea mays L.) is the most important cereal crop produced in Ghana. However, yield of the crop is generally low, producing just about 1.7 t/ha. The low yield is attributed to continuous use of local/unimproved varieties. Generally, hybrid varieties have proven to out-yield the local/unimproved varieties due to improved vigour. Development of hybrid varieties depend on good understanding of combining ability and inheritance of important quantitative traits such as grain yield (GY). 45 half-diallel crosses generated from 10 extra-early maturing yellow inbred lines were evaluated in 2015 under rain-fed conditions. The objectives were to determine the genetic control, breeding value and estimate heritability for GY and agronomic traits of the inbred lines under contrasting growing environments in Ghana. General combining ability (GCA) and specific combining ability (SCA) were important in the inheritance of GY and agronomic traits of the inbred lines. However, GCA was more important than SCA across environments to suggest that additive gene action was more important than non-additive gene action in the inheritance of GY and agronomic traits in the inbred lines. High broad-sense heritability, for GY and other agronomic traits indicated preponderance of additive gene action in trait expression, thus, selection based on phenotypic expression could be feasible. Inbred lines P1, P4 and P8 were good combiners for high GY. The genotype, P4 × P8, was identified as the ideal and most yielding single-cross hybrid across research environments and should be further tested on-farm before commercialization.  相似文献   
4.
Changes in vegetation caused by experimental leakage of natural gas The response of vegetation to natural gas leakage was studied in Central Bohemia, Czechoslovakia, in 1978–84. The gas used was of the following chemical composition: 93·8% methane, 3·6% ethane, 0·8% propane, 0·25% butane, 0·3% carbon dioxide. The test crops were planted in 60·5 m plots containing underground bores from which gas was released into the soil through distribution pipes. In addition, the response of some weed species was recorded. The important effects of contamination observed were restricted growth and decrease in the number of individuals present. A change in the green colour of leaves was recorded in Medicago sativa, Brassica oleracea var. acephala, Secale cereale, Lolium multiflorum. Beta vulgaris and Zea mays. An obvious shift of developmental stages was found in Solanum tuberosum. Helianthus annuus and Zea mays (delay of recruitment and blooming). Restricted or even failure of reproduction can be considered the typical effect of exposure to natural gas: this holds true especially for Allium cepa, Triticum aestivum, Hordeum distichon, Trifolium sp.div., Medicago sativa, and most of the weedy species. Various growth deformations, mostly found in the underground parts of the plants (tubers and roots in Solanum tuberosum, Beta vulgaris), can be ascribed to the unfavourable conditions of soil aeration. Plants of Chenopodium album and Medicago sativa growing in the vicinity of the gas release point had an increased number of stomata. There were changes in the course of the reflectance curves estimated in the population of Trifolium pratense subsp. sativum. There was a conspicuous decrease of the near infrared reflectance in the stand exposed to gas in comparison with the control. Decrease of coverage and density of the stands reduced species diversity and changes in the species' composition (reduction of sensitive species) are the general consequences of natural gas leakage. The first symptoms on the vegetation were observed after 15–30 days which corresponds to about 80–150 m3 of discharged gas.  相似文献   
5.
Progressive loss of virulence for goat kids was noticed when peste des petits ruminants (PPR) virus was passaged in Vero cells. While goats inoculated with the 60th passage suffered from the clinical PPR disease and mortality, goats inoculated with the 80th passage did not show any sign of the disease. If the progressive loss of virulence of the virus with passage continues, it will not be long before a homologous PPR vaccine will be obtained at the National Veterinary Institute, Vom.  相似文献   
6.
Plasminogen activators/Plasmin system plays pivotal role in regulating reproductive functions of mammals. Here, we examined the effects of modification of in vitro fertilization medium (IVF medium) with the addition of tissue‐type plasminogen activator (t‐PA), on bovine embryo development and quality, assessed by quantification of expression of various genes related to metabolism, oxidation, implantation and apoptosis. In addition, plasminogen activator activity (PAA) and plasminogen activator inhibition (PAI) were measured in the spent media. After conventional IVM, 2016 cumulus‐oocyte complexes (COCs) were divided into four groups with modified composition of the IVF medium containing t‐PA and/or its inhibitor epsilon‐aminocaproic acid (control, t‐PA, t‐PA+ε‐ACA, ε‐ACA). Presumptive zygotes were cultured for 8 days in synthetic oviductal fluid (SOF) medium; gene expression studies were carried out on morulae and blastocysts. t‐PA alone significantly suppressed cleavage and blastocyst formation rates, but this effect was neutralized by the addition of ε‐ACA. PAA in the treated group was significantly reduced by ε‐ACA, but without total elimination. Significant differences were detected in the expression of genes related to apoptosis and/or cell cycle arrest (BAX, BCL2L1, KAT2B) between embryos produced in t‐PA‐modified media and controls, giving an overall notion that the inferior developmental competence of treated embryos may be attributed to apoptotic phenomena induced by t‐PA. In conclusion, it appears that excessive t‐PA content in the IVF media, suppresses blastocyst formation rate, possibly due to induction of apoptotic phenomena.  相似文献   
7.
Abstract. An enzyme-linked immunosorbent assay (ELISA) for the demonstration of the virus of spring viraemia of carp (SVCV) in liver, kidney and spleen homogenates, and in infected cell cultures is described. The sensitivity of the method is 102·8–103·5 TCID50 0·lml−1 of the examined fluid. The specificity has been confirmed by the ELISA inhibition test and by results of virological examinations. Contamination with bacteria or fungi of samples taken from dead fish had no effect on the results of ELISA. Specific anti-SVCV sera were used successfully for the production of conjugates for the direct immunoperoxidase and immunofluorescence detection of SVCV in infected cell cultures.  相似文献   
8.
In a pilot survey to compare the relative prevalence of three diseases in apparently healthy White Fulani Zebu (WFZ) cattle slaughtered in Nigeria, sera from 80 randomly selected animals with no significant gross lesions on ante mortem and post mortem inspection were examined for antibodies to Brucella abortus, Dermatophilus congolensis and bovine leukaemia virus. Of the samples screened, 5.0, 8.8 and 2.0% showed serological evidence for brucellosis, cutaneous streptothricosis and bovine leukosis respectively.  相似文献   
9.
The feeding value of fresh pasture grazed in situ is determined by animal performance or productivity and could be relatively easily established for growing and lactating horses. Despite this, there is a lack of published information on the relative feeding value of different pastures and forages grazed by horses in New Zealand and the world. In addition, for adult breeding or non-breeding and young or adult sport or performance horses, the definition of feeding value and its determination remain problematic.

Limited information suggests that the feeding value of perennial ryegrass-based pasture in New Zealand for young growing horses is high, and growth rates for Thoroughbred horses fed solely on pasture in New Zealand are similar to those reported from the Northern Hemisphere where grain-based supplements are fed in addition to pasture or other forages. Attempts to assess the ability of fresh pastures to meet the nutrient requirements of horses are hampered by problems associated with determination of feed intake by grazing horses and lack of knowledge of the digestibility and utilisation of digested nutrients, including the relative bio availability of macro- and micro-minerals in pasture. A further challenge for future research is to determine the effect of herbage allowance and grazing behaviour, including pasture species preferences, on voluntary feed intake by grazing horses.

Grazing pasture has benefits for equine health and well-being including reduced risk of some nutrition-related disorders and reduced prevalence of stereotypic behaviour. Pastured horses have greater freedom for expression of natural behaviours including social interaction and exercise. However, grazing pasture is also associated with animal health problems, particularly parasitism and diseases related to pasture-associated toxins.  相似文献   
10.
Reports on the nutritional composition of cowpea leaves have been limited to a small number of lines and the palatability characteristics of leaves apparently have not been studied. This study was therefore undertaken on cowpea leaves to determine the nutrient composition of fifteen varieties and the sensory attributes of ten varieties grown in Ghana. Nutritional components studied were moisture, protein, phosphorus and ascorbic acid. The sensory attributes included leaf size, taste and overall acceptability. There were significant (p > 0.05) differences among varieties in all nutrient components (fresh and dry weight basis), leaf size and overall acceptability. The nutrient composition values, on a dry weight basis, ranged from 9.4 to 13.0% for moisture, 303.8 to 468.9 mg/100 g for phosphorus, 33.5 to 148.0 mg/100 g for ascorbic acid, and 27.1 to 34.7% for protein. Differences in the sensory scores of leaves for taste were not significant (p < 0.05). Overall acceptability positively correlated with leaf size. Moisture content was negatively correlated with overall acceptability, phosphorus and ascorbic acid. Results can be exploited in a breeding program to develop nutritionally superior and acceptable cowpea varieties which can be used for harvesting of both leaves and seeds.  相似文献   
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