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21.
A significant increase in milk production, averaging 164 litres per cow per lactation (a 4.8% increase), was seen after cows infected with gastrointestinal nematodes, paramphistomes and Fasciola hepatica were treated with broad-spectrum anthelmintics. Three hundred and ninety pairs of cows from eight herds with year-round calving were studied. One cow in each matched pair was given 7.5 mg/kg fenbendazole, 7.5 mg/kg levamisole hydrochloride and 15 mg/kg oxyclozanide in March, May and August of one year; the other cow in the pair received no anthelmintic. The number of nematode and trematode eggs was significantly decreased in the faeces of treated cows.  相似文献   
22.
The osteopontin gene may influence the fertility of water buffaloes because it is a protein present in sperm. The aim of this work was to identify polymorphisms in this gene and associate them with fertility parameters of animals kept under extensive grazing. A total of 306 male buffaloes older than 18 months, from two farms, one in the state of Amapá and the other in the state of Pará, Brazil were used in the study. Seven SNPs were identified in the regions studied. The polymorphisms were in gene positions 1478, 1513 and 1611 in the region 5′upstrem and positions 6690, 6737, 6925 and 6952 in the region amplified in intron 5. The SNPs were associated with the traits, namely scrotal circumference, scrotal volume, sperm motility, sperm concentration and sperm pathology. There were significant SNPs (p < 0.05) for all the traits. The SNP 6690 was significant for scrotal circumference, sperm concentration, sperm motility and sperm pathology and the SNP 6737 for scrotal volume. The genotype AA of SNP 6690 presented the highest averages for scrotal circumference, sperm concentration and motility and the lowest total number of sperm pathologies. For the scrotal volume trait, the animals with the largest volume were correlated with the presence of the genotype GG of SNP 6737. These results indicate a significance of the osteopontin gene as it seems to exert a substantial influence on the semen production traits of male buffaloes.  相似文献   
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Abstract

Extract

In the last 2 years, two papers have been published suggesting that current New Zealand reference criteria for diagnosing cobalt deficiency should be reviewed (Grace et al 2003), and they are conservatively high and lead to the over-diagnosis of vitamin B12 deficiency and ill-thriftiness in sheep (Gruner et al 2004). The comments refer to reference ranges cited by animal health diagnostic laboratories. These reference ranges were derived from the paper by Clark et al (1989 Clark, RG, Wright, DF, Millar, KR and Rowland, JD. 1989. Reference curves to diagnose cobalt deficiency in sheep using liver and serum vitamin B12 levels.. New Zealand Veterinary Journal, 37: 711. [Taylor &; Francis Online], [Web of Science ®] [Google Scholar]), which reviewed data from published and unpublished weight gain response trials preceding that date. The review included all published trials in New Zealand and as many unpublished trials that the authors could obtain. They involved serum vitamin B12 data from 54 trials and liver vitamin B12 data from 21 trials. It was stated that more data from trials conducted in autumn were required to reliably determine an autumn response curve. In addition, it was envisaged that as other trial data became available the reference curves could be upgraded (Clark et al 1985 Clark, RG, Wright, DF and Millar, KR. 1985. A proposed new approach and protocol to defining mineral deficiencies using reference curves. Cobalt deficiency in young sheep is used as a model.. New Zealand Veterinary Journal, 33: 15. [Taylor &; Francis Online], [Web of Science ®] [Google Scholar]).  相似文献   
25.
Defoliation of well-stocked, 10–12-year-old P. parula, and younger E. saligna/grandis and E. cloeziana standsby the larval stages of a geometrid moth Buzura edwardsi Walker, recently indicates that this is a potentially important forest pest in the Melsetter district, one of the major areas of pine and eucalypt afforestation in Rhodesia.

Field observations of the habitsand life cycle of the pest and the damage it causes are recorded, as well as its biological control which, in normal seasons, appears to be adequate in keeping infestation at tolerable levels.

However, the necessity is stressed for immediate specialist investigation into effecting permanent control of this economically important forest pest, preferably by biological means.  相似文献   
26.
Tuberculosis, caused by Mycobacterium bovis, was first diagnosed in African buffalo in South Africa's Kruger National Park in 1990. Over the past 15 years the disease has spread northwards leaving only the most northern buffalo herds unaffected. Evidence suggests that 10 other small and large mammalian species, including large predators, are spillover hosts. Wildlife tuberculosis has also been diagnosed in several adjacent private game reserves and in the Hluhluwe-iMfolozi Park, the third largest game reserve in South Africa. The tuberculosis epidemic has a number of implications, for which the full effect of some might only be seen in the long-term. Potential negative long-term effects on the population dynamics of certain social animal species and the direct threat for the survival of endangered species pose particular problems for wildlife conservationists. On the other hand, the risk of spillover infection to neighboring communal cattle raises concerns about human health at the wildlife-livestock-human interface, not only along the western boundary of Kruger National Park, but also with regards to the joint development of the Greater Limpopo Transfrontier Conservation Area with Zimbabwe and Mozambique. From an economic point of view, wildlife tuberculosis has resulted in national and international trade restrictions for affected species. The lack of diagnostic tools for most species and the absence of an effective vaccine make it currently impossible to contain and control this disease within an infected free-ranging ecosystem. Veterinary researchers and policy-makers have recognized the need to intensify research on this disease and the need to develop tools for control, initially targeting buffalo and lion.  相似文献   
27.
Bovine tuberculosis is endemic in African buffalo and a number of other wildlife species in the Kruger National Park (KNP) and Hluhluwe-iMfolozi Park (HiP) in South Africa. It was thought that the infection had been introduced into the KNP ecosystem through direct contact between cattle and buffalo, a hypothesis which was confirmed in this study by IS6110 and PGRS restriction fragment length polymorphism (RFLP) typing. The molecular characterisation of 189 Mycobacterium bovis isolates from nine wildlife species in the HiP, including three smaller associated parks, and the Kruger National Park with adjacent areas showed that the respective epidemics were each caused by an infiltration of a single M. bovis genotype. The two M. bovis strains had different genetic profiles, as demonstrated by hybridisation with the IS6110 and PGRS RFLP probes, as well as with regard to evidence of evolutionary changes to the IS profile. While the M. bovis type in HiP was transmitted between buffaloes and to at least baboon, bushpig and lion without obvious genetic changes in the RFLP patterns, in the KNP a dominant strain was represented in 73% of the M. bovis isolates, whilst the remaining 27% were variants of this strain. No species-specific variants were observed, except for one IS6110 type which was found only in a group of five epidemiologically related greater kudu. This finding was attributed to species-specific behaviour patterns rather than an advanced host-pathogen interaction.  相似文献   
28.
Possible effects of repeated hormonal treatments and laparoscopic ovum pick-up (LOPU) on the efficiency of oocyte recovery rate and quality were determined in sheep and goats. In six adult Merino sheep and five Criolla goats, ovarian status was synchronized by a prostaglandin F(2 alpha) analogue and the insertion of an intravaginal sponge 48 h later. Follicle development was stimulated by a single dose of FSH (60 mg NIH-FSH-P1) plus a single dose of equine chorionic gonadotrophin (eCG; 300 UI). The first FSH/eCG doses were administered 48 h after the sponge insertion, being repeated every 4 days to complete a total of four treatments in sheep and three in goats. Follicles in both ovaries were categorized according to their diameter and follicular fluid was aspirated under laparoscopic observation without a vacuum pump. In sheep, during a 12-day-period, a total of 347 follicles were aspirated with a recovery rate of 46.9%. In goats, during an 8-day-period, 219 follicles were aspirated with a recovery rate of 45.6%. In both species, there were no significant differences in the number of aspirated follicles, oocyte recovery rate and good quality oocyte recovery rate. However, in sheep the oocyte recovery rate was higher for large follicles, whereas in goats no such effect was detected. In summary, current results indicate that retrieval of oocytes can be maximized, without affecting oocyte quality, by repeating 'oneshot' FSH/eCG regimes and LOPUs at intervals as short as 4 days.  相似文献   
29.
Lion sera from the Kruger National Park (KNP) dating back to 1977 and from the Etosha National Park (ENP), obtained from 1989 to 1991, have been analysed by ELISA and Western blot analyses using a genetically engineered antigen representing the p24 structural protein of feline immunodeficiency virus (FIV). It was concluded that some 83% of 98 KNP lion sera reacted with the p24 antigen, while none of 28 ENP lion sera reacted. A few other KNP felids (cheetahs and genets) gave samples that did not react with the FIV p24 antigen. For the KNP lions, apart from a lower prevalence in cubs (50%), no particular trends were demonstrated in terms of age, sex, date or origins of the samples. In Western blot and radio-immunoprecipitation analyses the lion sera reacted with the engineered p24 antigen, as well as with the p15 and p24 gag proteins and the p50 gag precursor protein from FIV, indicating that the agent is probably a lentivirus related to FIV. The ELISA with the engineered p24 antigen required less serum and appears to be more sensitive at detecting FIV-reactive antibodies than assays with available commercial kits.  相似文献   
30.
The availability of safe, commercially prepared stock feed for production animals is an important step in ensuring animal health and welfare and the safety of food animal products for human consumption. Animal feed quality assurance programs include microbiological monitoring of raw materials, mill equipment and finished feed. Over a period of 16 years, 23,963 samples for Salmonella culture and serotyping were collected from 22 stock feed mills. A multivariable generalized linear mixed model (GLMM) was used to identify mill and sample type factors that increase the odds of detecting Salmonella. The odds of detecting a Salmonella positive sample was greatest in samples from raw materials and in mills that processed restricted animal material (RAM). The percentage of positive samples ranged from 7.2% in 2003 to 2.8% in 2017. Of the 1,069 positive samples, 976 were serotyped with 61 different Salmonella serotypes isolated. The serotype most frequently isolated from raw materials was S. Agona, (n = 108) whilst S. Anatum was the serotype most frequently isolated from equipment and finished feed (n = 156). The diversity of Salmonella serotypes differed between mills and different stages of the production line. Microbiological monitoring in the commercial preparation of animal feed in Australian stock feed mills guides the implementation of quality control measures and risk mitigation strategies thereby reducing the prevalence and diversity of potentially zoonotic bacteria such as Salmonella, enhancing food safety for both animal and consumer.  相似文献   
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