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131.
A saddle that does not fit either a horse or a rider correctly has potentially far reaching consequences for both horse and rider health. The saddle should be assessed off and on the horse, without and with a rider. The fit of the saddle for both the horse and rider must be evaluated. A well‐fitted saddle should distribute weight evenly via the panels to the horse's thoracic region, with complete clearance of the spinous processes by the gullet. The saddle should remain fairly still during ridden exercise at all paces. The saddle must also fit the rider to enable them to sit in balance. Signs of an ill‐fitting saddle include equine thoracolumbar pain, focal swellings under the saddle, ruffling of the hair, dry spots under the saddle immediately after exercise surrounded by sweat, and abnormal hair wear. If a saddle does not fit the rider, the rider may not be able to ride in balance with the horse, and this may induce equine thoracolumbar pain. A saddle of inappropriate size and shape for the rider may induce rider back pain, ‘hip’ pain, sores under the ‘seat bones’ and perineal injuries.  相似文献   
132.
Three new varieties of Passiflora hybrids were developed from crosses between P. sublanceolata J. M. MacDougal (ex P. palmeri var. sublanceolata Killip) versus P. foetida var. foetida L. Twenty putative hybrids were analyzed. Hybridizations were confirmed by RAPD and SSR markers. The RAPD primer UBC11 (5′-CCGGCCTTAC-3′) generated informative bands. The SSR primer A08FP1 amplified species-specific fragments and heterozygote status was observed with the two parent bands 240 and 280 bp. The molecular markers generated by primers were analyzed in terms of the presence or absence of specific informative bands. The morphological characterization of the hybrids enabled their differentiation into three groups, identified as: (1) Passiflora ‘Alva’, composed of five hybrid plants with white flowers, large corona, light purple filaments at base, white and purple/white banding to apex; (2) P. ‘Aninha’, composed of six hybrid plants with pale pink flowers, corona filaments reddish/purple at base, white, purple/white banding to apex; (3) P. ‘Priscilla’, composed of nine hybrid plants with white flowers, small corona, filaments dark purple at base, white and purple to apex. The genomic homology of parent plants was verified by cytogenetic analysis. Both parents were 2n = 22. Meiosis was regular in genitors and hybrids. Aneuploidy was observed at hybrid groups P. ‘Alva’ and P. ‘Priscilla’ (2n = 20). Other authors had already observed the same number of chromosomes for some P. foetida genotypes. Obtaining valuable interspecific hybrids opens up new perspectives to offer opportunities in agribusiness for producers and to arouse the interest of consumers into using passion flowers in the Brazilian ornamental plant market.  相似文献   
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134.
This study addresses the potential risk to the genetic resources of UK sheep breeds from endemism. Twelve native breeds are analysed that exist in significant numbers and continue to be commercially farmed livestock. The breeds were selected to represent regions of the British Isles: North of England hill breeds (Herdwick, Rough Fell, Lonk, Dalesbred), South of England breeds (Southdown, Romney, Devon Closewool, Exmoor Horn), Scottish breed (South Country Cheviot) and Welsh/Welsh border breeds (Welsh Hill Speckled Face, South Wales Mountain (Nelson), Clun Forest).For each breed, numerical data were collected in collaboration with breed society members and analysed in terms of population size and structure together with the extent of their geographical range. The number of flocks per breed proved to be highly variable, questioning the assumption that has been made that the number of breeding units can be disregarded in the calculations of endangerment. The data also indicated that an average flock size for a breed cannot be estimated to gain an insight of the population structure, since this parameter was found to vary considerably within and between breeds. The endemism was best illustrated in the breed maps which clearly highlighted the degree to which each breed was associated with a distinct geographical area. From the maps, ten of the twelve breeds analysed were concentrated, but the flocks of two breeds were visually more dispersed. In numerical terms, the ten breeds were found to have up to 95% of their breed numbers concentrated within a radius of 65 km from the mean centre of each breed.The study provides a valuable foundation for future research into genetic diversity within and between the sheep breeds analysed, a baseline of information to enable population trends to be examined and a robust evidence-base for policy decisions on Farm Animal Genetic Resources (FAnGR).  相似文献   
135.
A commercial vaccine containing modified-live bovine viral diarrhea virus (BVDV; types 1 and 2) was administered to one group of 22 peripubertal bulls 28 days before intranasal inoculation with a type 1 strain of BVDV. A second group of 23 peripubertal bulls did not receive the modified-live BVDV vaccine before intranasal inoculation. Ten of 23 unvaccinated bulls--but none of the vaccinated bulls--developed a persistent testicular infection as determined by immunohistochemistry and polymerase chain reaction. Results of this study indicate that administration of a modified-live vaccine containing BVDV can prevent persistent testicular infection if peripubertal bulls are vaccinated before viral exposure.  相似文献   
136.
Objective   To compare the effectiveness of a single long-acting injection of moxidectin, given in either summer or winter, with a two-summer ('standard') treatment strategy for controlling gastrointestinal nematodes in spring-lambing Merino ewes.
Design   A replicated study over 2 years in the high winter rainfall environment of western Victoria.
Methods   Measures of worm infection were worm egg counts of ewes and total worm counts of tracer lambs. Measures of production were body weight, proportion of pregnant ewes and number of weaned lambs.
Results   The egg counts of ewes given the standard strategy followed a characteristic pattern, rising to 300 to 600 eggs per gram before the second summer treatment in February. During this time, ewes given long-acting moxidectin in December had zero or negligible counts. There were no consistent differences between tracer worm counts or production measures for the two groups treated in summer, but when data from both years were pooled, the total egg output from December to May was significantly lower for ewes treated with long-acting moxidectin in December. Ewes not treated during summer had lower body weights, and higher worm egg counts and tracer worm counts, showing that this was not a suitable strategy at that time of the year. However, following treatment with long-acting moxidectin in winter, ewes had rapid compensatory weight gain and lower egg output than ewes treated in summer.
Conclusion   A single injection of long-acting moxidectin in December is an effective treatment strategy for Merino ewes lambing in spring.  相似文献   
137.
Twenty mixed-breed adult laying hens from a small farm flock in Iowa were clinically normal but had been exposed to chips of lead-based paint in their environment. These chickens were brought to the Iowa State University Veterinary Diagnostic Laboratory, Ames, Iowa, where the concentration of lead in blood, eggs (yolk, albumen, and shell), and tissues (liver, kidney, muscle, and ovary) from 5 selected chickens was determined over a period of 9 days. Blood lead levels ranged from less than 50 to 760 ppb. Lead contamination of the yolks varied from less than 20 to 400 ppb, and shells were found to contain up to 450 ppb lead. Albumen contained no detectable amount. Lead content of the egg yolks strongly correlated with blood lead levels. Deposition of lead in the shells did not correlate well with blood lead levels. Mean tissue lead accumulation was highest in kidneys (1,360 ppb), with livers ranking second (500 ppb) and ovarian tissue third (320 ppb). Muscle contained the lowest level of lead (280 ppb). Lead contamination of egg yolks and edible chicken tissues represents a potential public health hazard, especially to children repeatedly consuming eggs from contaminated family-owned flocks.  相似文献   
138.
An experiment was carried out to examine silage fermentation, effluent production and aerobic stability in unwilted grass silage, which was either ensiled without additive or with a commercially available blend of ammonium hexamethanoate, ammonium hexapropionate and octanoic acid (6 l t?1, Maxgrass, BP Chemicals Ltd., Northwich, UK) and to determine alternative approaches to obtaining the same performance in finishing beef cattle. Seventy‐two Limousin × Friesian and Charolais × Friesian steers (mean initial live weight 424 kg s.d. 28·3) were blocked into groups of nine according to live weight and previous performance and offered silage, either with or without the additive, and supplemented with 0, 1·5, 3·0 or 4·5 kg d?1 of a concentrate with a crude protein content of 150 g kg?1 DM or allocated to a pre‐experimental slaughter group to enable calculation of daily carcass gain. Daily silage intakes were recorded for 112 days. At the end of the experiment, all cattle were slaughtered and daily carcass gain, omental, mesenteric, perinephric and retroperitoneal fat depots [kidney‐knob and channel fat (KKCF)], fatness, conformation, subcutaneous fat depth over M. longissimus dorsi muscle and carcass fat, protein and bone contents were assessed. Across all levels of supplementation, cattle offered the silage with the additive showed significantly (P < 0·001) higher daily DM intakes than those offered the silage without additive. Cattle offered the silage with the additive but unsupplemented had significantly (P < 0·001) higher daily carcass gains than those offered the silage without additive and unsupplemented. The response in carcass gain was 76 and 35 g kg?1 additional concentrate for the silages with and without the additive respectively.  相似文献   
139.
140.
The effectiveness of measuring petiole sap nitrate-nitrogen concentration (PSNC) using ion selective electrode (ISE) has been scrutinized due to claims that PSNC poorly predicts leaf tissue nitrogen concentration (LTNC) or crop yield. This study evaluated the relationship among PSNC, LTNC, and marketable yield of tomato (Solanum lycopersicum L.). Two tomato trials were conducted using seepage irrigation and controlled-release fertilizer (CRF) in fall 2011 and 2012. At 15 days intervals, six most recently mature leaves were collected to measure PSNC and LTNC. PSNC and LTNC declined throughout the growing seasons, but PSNC was affected by weather. PSNC and LTNC were correlated (P = 0.0001, r = 0.38), though not meaningfully. PSNC and LTNC correlated negatively and positively with crop yield in most correlations, respectively. Correlations of CRFs and soluble fertilizers (SFs) separately, did not improve relationships. Measuring LTNC may be a more reliable nutrient management tool compared to PSNC measured using an ISE.  相似文献   
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