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101.
The incidence, calf morbidity and mortality due to Theileria parva infections in smallholder dairy farms in Murang'a District, Kenya 总被引:1,自引:0,他引:1
A prospective observational study was conducted among smallholder dairy farmers in Murang'a District, Kenya, to estimate the incidence of Theileria parva infections, as well as calf morbidity and mortality caused by the infection. The study was conducted between March 1995 and August 1996, in five cohorts of female calves from birth to six months of age from different agro-ecological zones (AEZs) and grazing-system strata shown previously to have varying prevalences of T. parva infection. A total of 188 smallholder dairy farms with 225 female calves were selected purposively by five AEZ-grazing strata. All recruited calves were visited within the first two weeks of life and thereafter at biweekly intervals up to the age of six months. The mean number of cattle in these smallholder farms was 2.6. Both exotic and indigenous breeds of cattle and their crosses were present, with the former predominating. The incidence (27-54%) of sero-conversion to T. parva in an ELISA test was significantly different (p < 0.05) across the five AEZ-grazing strata and increased with lower elevation and unrestricted grazing. Calf morbidity and mortality were also variable across the AEZ-grazing strata. East Coast fever (ECF) was the highest-incidence cause calf morbidity and mortality (relative to other diseases). There are great differences in the epidemiology of ECF within a small area and this implies that there is need to carefully consider different ECF control strategies in different AEZ-grazing strata. 相似文献
102.
103.
Levine DG Smith JJ Richardson DW Brown V Beech J Habecker P Adam E 《Journal of the American Veterinary Medical Association》2007,231(3):437-441
CASE DESCRIPTION: A 6-month-old male Bactrian camel was examined because of a 3-week history of lameness of the left hind limb. CLINICAL FINDINGS: Lameness was initially detected in the left hind limb but resolved and was detected in the right hind limb during treatment. Lameness increased during periods of rapid growth. Radiography revealed multiple small opacities of the medullary cavity of several long bones throughout treatment. Core bone biopsies of lesions in the tibiae revealed lamellar bone with areas of loose connective tissue, osteoblasts in the medullary cavity, and periosteal new bone formation, all which were consistent with panosteitis. TREATMENT AND OUTCOME: Palliative treatment was attempted with epidural and transdermal administration of analgesics. Flunixin meglumine was administered PO, which coincided with an abrupt increase in serum creatinine concentration. Performance of multiple diagnostic bone biopsies led to remission of clinical signs of pain. CLINICAL RELEVANCE: Panosteitis should be a differential diagnosis for shifting limb lameness in young camels. Bone biopsies can be useful for diagnosis of panosteitis and possible relief of pain associated with the disease. Bactrian camels may be susceptible to the renal toxicity of flunixin meglumine, especially when dehydrated. 相似文献
104.
1. There were no significant differences in the mean time of oviposition, distribution of ovipositions over the 24 h or proportion of eggs laid in the modal 8 h when conventionally-lit hens were compared with hens which received interrupted lighting with the same apparent daylength. 2. Intermittently-lit hens performed 25% less feeding activity than conventionally-lit hens, but without a significant reduction in mean food intake. There were genetic differences in response of feeding rate to interrupted lighting. 3. Intermittently-illuminated hens consumed about 20% of their food during the scotoperiods which interrupted the apparent day of a 1.5L:0.5D:10(0.5L:0.5D):4L:8D regimen, although there was significant genetic variation from 10 to 22%. None of the genotypes ate during the 8-h night. 4. Across 4 genotypes neither crop weight nor rate of crop emptying was affected by the lighting treatments, although a heavier mean crop weight under interrupted lighting approached significance in one breed (P less than 0.10). 5. Interrupted lighting did not cause any ocular disorders. 相似文献
105.
In a 2-yr study a total of 120 Suffolk and Suffolk-cross ewe lambs, approximately 3 mo of age, were assigned within weight strata to one of three treatments: 1) control, pasture only (C), 2) .09 kg soybean meal/(hd.d) (SBM) plus pasture or 3) .45 kg whole shelled corn/(hd.) plus pasture to compare growth and reproductive performance and to determine lamb selectivity of forage quality and type. Each year, supplements were offered from June through the 3rd wk in November. Ewe lambs were managed as one flock on Kentucky bluegrass (Poa pratensis L.) and tall fescue (Festuca arundinacea Schreb.) pastures except for a brief daily supplementation period when all lambs were brought into a corral and sorted into treatment groups for the feeding. Ewe lambs were exposed to fertile rams from October 1 through the 3rd wk of November each year. Growth rates of ewe lambs grazing pasture alone were slower than those of corn-supplemented ewe lambs and were comparable to those of SBM-supplemented ewe lambs, but reproductive performances were similar (P greater than .05). Date of first detected rise in serum concentrations of progesterone and date of first observed estrus and lambing performance were similar (P greater than .05) among treatments for each year. Compared to hand-clipped forage, forage samples collected by esophageally fistulated lambs were higher (P less than .05) in crude protein and lower (P less than .05) in acid detergent fiber each year, indicating that lambs selectively grazed higher-quality forage. These data indicate that neither protein nor energy limited growth or reproductive performance of these ewe lambs. 相似文献
106.
A longitudinal study of veterinary students and recent graduates: 3. Perceptions of veterinary education 总被引:1,自引:1,他引:0
Objective To examine the attitudes and opinions on veterinary education at the beginning and end of the veterinary course, and after graduation.
Design Longitudinal study.
Population Students – 154 in all – who began studying veterinary science at The University of Queensland in 1985 and 1986.
Procedure Questionnaires were completed in the first and fifth year of the course and in the second year after graduation. The data were analysed using the SAS System for Windows.
Results When they entered the course, the students were looking forward more to learning about animals than about basic sciences. At fifth year and after graduation most believed that more emphasis should have been placed on all facets of their education except the basic sciences. It may be difficult to increase this emphasis without placing undue pressure on the students, although more than half of the fifth year students and graduates agreed that there is much in the curriculum that is not needed by a practising veterinarian. Only one-third or less agreed that veterinarians are well equipped to practise veterinary science immediately they graduate. There was no relationship between the level of agreement with this statement, and the academic grades obtained.
Conclusions A majority of veterinary graduates do not believe that they are well equipped to practice immediately they graduate. They believe that more emphasis should have been placed on most facets of their education, but, conversely, that there is much in the curriculum that is not needed by a practising veterinarian. 相似文献
Design Longitudinal study.
Population Students – 154 in all – who began studying veterinary science at The University of Queensland in 1985 and 1986.
Procedure Questionnaires were completed in the first and fifth year of the course and in the second year after graduation. The data were analysed using the SAS System for Windows.
Results When they entered the course, the students were looking forward more to learning about animals than about basic sciences. At fifth year and after graduation most believed that more emphasis should have been placed on all facets of their education except the basic sciences. It may be difficult to increase this emphasis without placing undue pressure on the students, although more than half of the fifth year students and graduates agreed that there is much in the curriculum that is not needed by a practising veterinarian. Only one-third or less agreed that veterinarians are well equipped to practise veterinary science immediately they graduate. There was no relationship between the level of agreement with this statement, and the academic grades obtained.
Conclusions A majority of veterinary graduates do not believe that they are well equipped to practice immediately they graduate. They believe that more emphasis should have been placed on most facets of their education, but, conversely, that there is much in the curriculum that is not needed by a practising veterinarian. 相似文献
107.
Gregory Scott W. Guthrie Perry James W. Avault 《Journal of the World Aquaculture Society》1988,19(3):118-126
Juvenile prawns (Macrobrachium rosenbergii) were stocked at 37,050/ha and golden shiner (Noremigonus crysoleucas) fry at 321,100/ha into 16 earthen ponds at Rockefeller Wildlife Refuge, Grand Chenier, Louisiana. Four replicated treatments were tested: fed prawn monoculture, fed shiner monoculture, fed prawn and fed shiner polyculture, and unfed prawn fed shiner polyculture. The study lasted 149 days. There were no significant differences in growth between prawns fed in monoculture and prawns fed in polyculture (P > 0.05). However, fed prawns grew significantly larger (P < 0.05) than unfed prawns. Prawn survival in all treatments combined averaged 63%. Survival was significantly higher (P < 0.05) for fed prawns than for unfed prawns. Prawn yields averaged 533 kg/ha, when all treatments were combined. Yield was significantly higher (P < 0.05) for prawns grown with shiners and for prawns that received supplemental feed. Growth was significantly higher (P < 0.05) for shiners grown with fed prawns than for shiners grown with unfed prawns. Shiner survival averaged 33% and was significantly higher (P < 0.05) in monoculture than in polyculture. Yield for all ponds averaged 392 kg/ha, with no significant differences between treatments (P > 0.05). 相似文献
108.
109.
Extraosseous chondrosarcomas are uncommon in the dog, and those originating in the lung are rare. This report presents a 9-year-old Beagle dog with a pulmonary mass which caused depression, fever, tachypnea, cough, and laboratory abnormalities. The mass was composed predominantly of chondroid tissue, and was histologically diagnosed as chondrosarcoma. 相似文献
110.
Segmentation of the main light period of an 8L:4D:2L:10D regimen into 30 min light, 30 min dark did not affect total feeding activity, rate of feeding or total intake of laying hens. When 15 min light and 45 min dark was provided each hour feeding activity and food intake were reduced, while rate of feeding and feeding during the dark periods increased. No feeding occurred in the 10 h 'night'. Hens subjected to interrupted lighting showed less feeding activity than those on a 14L:10D regimen. Insertion of a 4 h dark period in the 14 h subjective day of laying hens increased their rate of feeding, but reduced total intake. The pattern of feeding activity depended on the position of the 4 h dark period. The largest modification of feeding activity occurred on a 8L:4D:2L:10D regimen; 20% of activity occurred in the last 2 h of the apparent day. Feeding occurred during the 4 h dark period, but not during the 10 h 'night'. 相似文献