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1.
A 12-year-old Quarter horse gelding was presented for evaluation of severe right forelimb lameness, 2 draining tracts over the lateral aspect of the right proximal antebrachium, and weight loss. A presumptive diagnosis of blastomycotic osteomyelitis was established based on radiographs and cytology of the exudate. This diagnosis was confirmed at necropsy.  相似文献   
2.
The present study was carried out to investigate the pattern of apoptosis in the healthy antral and atretic follicles of Philippine swamp buffaloes (BU) in comparison with Holstein-Friesian (HF) cows. Paraffin sections of healthy follicles and various stages of atretic follicles were stained using the terminal deoxynucleotidyl transferase (TdT)-mediated biotinylated deoxyuridine triphosphates (dUTP) nick end-labelling (TUNEL) method to detect DNA fragmentation and cleaved caspase-3 antibody to detect cells committed to undergo apoptosis. Five equidistant areas of a follicle were counted for the presence of TUNEL- and caspase-3-positive cells. Healthy follicles of BU and HF contained no TUNEL-positive cells in the granulosa and theca layer but showed some caspase-3 positivity. The granulosa layer of advanced atretic follicles showed a significantly higher frequency of caspase-3 positivity than the healthy and early atretic follicles in both breeds. The frequency of caspase-3-positive cells of BU was significantly higher than HF in the granulosa layer of healthy, early atretic and advanced atretic follicles. In the theca interna layer, BU and HF showed a significantly lower and higher frequency of TUNEL-positive cells in the late atretic follicles compared with advanced atretic follicle, respectively. However, the frequency of caspase-3-positive cells of both BU and HF in the late atretic follicles was significantly higher than the advanced atretic follicles in the theca interna layer. These results indicate that caspase-3 and DNA fragmentation is involved in the buffalo ovarian apoptotic process.  相似文献   
3.
An experiment was conducted to establish the effects of feeding refined soy oil (RSO) or whole soybeans (WSB) containing soy oil on DMI, animal performance, and enteric methane (CH4) emissions in young bulls. Thirty-six Charolais and Limousin cross-bred, young beef bulls (338 +/- 27 kg of BW, 218 +/- 17 d of age at the beginning of the experiment) were blocked by BW, age, and breed before being assigned in a randomized complete block design to 1 of 3 experimental treatments (n = 12). The experimental period lasted for 103 d, with enteric CH4 output recorded for 2 periods of 5 consecutive days on d 37 to 41 and d 79 to 83. The 3 dietary treatments consisted of a barley/soybean meal-based concentrate with 0 g/d of RSO; oil from WSB as 6% of DMI (WSB treatment); and oil from RSO as 6% of DMI (RSO treatment). Each diet had a 10:90 forage:concentrate ratio, using barley straw as the forage source. Diet affected DMI (P < or = 0.001) and GE intake (P < 0.05 during the CH4 measurement periods), with the WSB treatment producing the lowest values. The addition of WSB decreased ADG (P < 0.05) compared with the RSO treatment. The WSB treatment also decreased (P < 0.05) average daily carcass gain (ADCG). Both the RSO and WSB concentrates decreased (P < 0.05 to P < 0.001) daily enteric CH4 output when expressed in terms of liters per day, liters per kilogram of DMI, percentage of GE intake, liters per kilogram of ADG, and liters per kilogram of ADCG. Diet had no effect (P = 0.557) on ruminal protozoal numbers. The reductions in enteric CH4 were achieved at relatively high oil inclusion levels. Such oil levels have previously been reported to decrease DMI of high-forage diets, although no effect on DMI was noted with the low-forage diets fed in this experiment. This impact on DMI of high-forage diets may limit the range of diets for which this CH4 reduction strategy may be applicable. The inclusion level of WSB in the current experiment (27%) was beyond the palatability threshold of the bulls used and resulted in a marked decline in intake and performance. Therefore, WSB may have a role to play in ruminant diets, but only at a reduced inclusion rate.  相似文献   
4.
An outbreak of ringworm in sheep in Ireland caused by Trichophyton verrucosum is described. The flock consisted of 110 sheep and two separate groups within the flock were affected. Eleven of the first group of 23 sheep and five of the second group of 25 sheep showed lesions. Contact with infected cattle and fomites contaminated by the cattle are believed to have caused the outbreak. An excellent response was obtained in both infected groups by treatment with griseofulvin at a dose rate of 7.5 mg/kg daily for seven days.  相似文献   
5.
Objective To measure changes to the perineal bare area, local tissue reaction and healing responses of young sheep, following intradermal administration of cetrimide and polyvinylpyrrolidone (PVP), with and without ethanol, to the breech and tail. Method A needle‐less injector was used to deposit formulations containing 40 g/L cetrimide and 30 g/L PVP (group 2) or 20 g/L cetrimide, 30 g/L PVP and 15 g/L ethanol (group 3), within the dermis of the tail and the region surrounding the perineal bare breech area of groups (N = 8) of Merino weaner sheep. The dimensions of the perineal bare area (length, width and diagonal distances left and right) and tail width were recorded before and at intervals after treatment for 60 days. Observations of swelling and bruising and scab formation at the treatment sites were recorded for up to 35 days after treatment. Rectal temperatures were monitored for up to 35 days after treatment and bodyweight for up to 60 days after treatment. An untreated control group (group 1) was included. Results Comparison of day ‐3 and day 35 measurement data showed that both treated groups had significantly (P < 0.05) wider breech bare areas compared to the untreated controls and that group 2 sheep had significantly (P < 0.05) longer breech bare areas compared to group 3 sheep or to the untreated controls, which were not significantly different. At this time scabs were still firmly in place on many treated sheep. At day 35 there was no increase in tail bare area caused by either treatment. By day 60 there was no significant difference between the treated and control groups in either the breech or tail regions indicating that the changes present at day 35, were not permanent. Mean weight gain in the groups throughout the 60‐day interval was unaffected by treatment. Intradermal treatment was associated with a significant elevation in body temperature. This effect lasted for 3 days and was associated with signs of discomfort and depressed appearance in at least some of the treated sheep. Bruising was mild to severe in all treated sheep within two days of treatment but was not evident in any sheep by day 21. Mild to moderate swelling was also associated with treatment but was not uniform across sheep in the groups. The tail of one sheep was severely swollen for several days. Swelling remained obvious in most treated sheep until day 14 but was not present at day 21. Conclusion Under the conditions of this study intradermal injection of cetrimide had no permanent effect on bare area measurements on the breech or the amount of wool‐bearing skin on the tail. It also caused signs of discomfort and pain that raise welfare concerns.  相似文献   
6.
Tuberculosis, associated with Mycobacterium bovis infection, occurs infrequently in sheep. A sheep flock, which was potentially exposed to a high level of infection from in-contact tuberculous cattle, was examined for evidence of infection. Six sheep that had given a positive reaction to the comparative intradermal tuberculin test were examined post mortem. Tuberculous lesions were present in four of these sheep. Lesion morphology and distribution in the sheep was similar to that in cattle. M. bovis was cultured from the lesions and the isolates were strain typed by spoligotyping and variable number of tandem repeats (VNTR) typing. Tuberculin-reacting sheep also reacted positively to an assay for in vitro release of interferon-gamma. This paper describes the first report of an outbreak of tuberculosis in sheep in either Britain or Ireland. The report describes immunology and pathology findings and, using molecular typing techniques, suggests that the sheep had been infected from in-contact cattle.  相似文献   
7.
A geographic information system (GIS) was constructed using remote sensing (RS) and landscape feature data together with Calicophoron daubneyi positive survey records from 197 georeferenced ovine farms with animals pasturing in a 3971 km(2) area of the southern Italian Apennines. The objective was to study the spatial distribution of this rumen fluke, identify environmental features that influence its distribution, and develop a preliminary risk assessment model. The GIS for the study area was constructed utilizing the following environmental variables: normalized difference vegetation index (NDVI), land cover, elevation, slope, aspect, and total length of rivers. These variables were then calculated for "buffer zones" consisting of the areas included in a circle of 3 km diameter centered on 197 farms. The environmental data obtained from GIS and RS and from data taken by the veterinarians on the field (stocking rate and presence of streams, springs and brooks on pasture) were analyzed by univariate (Spearman and ANOVA) and multivariate (discriminant) statistical analyses using the farm coprological status (positive/negative) as the dependent variable. Sheep on 32 of the 197 (16.2%) farms, were positive for C. daubneyi, with an average intensity of 52 epg. A multivariate stepwise discriminant analysis model was developed that included moors and heathland, sclerophyllous and coniferous forest vegetation, autumn-winter NDVI and presence of streams, springs and brooks on pasture. The variables entered in the model were also correlated with C. daubneyi positive farms in the univariate tests and are consistent with the environmental requirements of C. daubneyi and its snail intermediate host.  相似文献   
8.
The aim of the present study was to evaluate the effects of different medium replacement intervals on the viability, antral cavity formation, growth and in vitro maturation (IVM) of oocytes from caprine and ovine pre‐antral follicles. Pre‐antral ovarian follicles (≥150 μm) were isolated from the ovarian cortex of goats and sheep and were individually cultured for 24 days using two different medium replacement intervals [2 days (T1) or 6 days (T2)]. Follicle development was evaluated on the basis of antral cavity formation, increases in follicular diameter and the presence of healthy cumulus oocyte complexes and fully grown oocytes. For caprine species, results showed a higher percentage (p < 0.05) of viable follicles in T1 than T2 from day 6 until the end of the culture. In addition, when comparing both treatments after the same culture duration, the rate of antrum formation was significantly higher in T1 than in T2 from day 12 onwards. Yet, in ovines, when both treatments were compared on day 24 of the culture, there were more viable follicles in T2 than in T1 (p < 0.05). In the caprine species, percentages of fully grown oocytes (≥110 μm) acceptable for IVM after 24 days of culture were significantly higher in normal follicles cultured in T1 (30.0%) than in T2 (6.7%; p < 0.05). On the other hand, in ovines, at the end of the culture, the percentage of oocytes destined for IVM was higher in T2 than in T1 (23.5% vs 2.9%; p < 0.05). In conclusion, under the same conditions, the frequency of medium replacement significantly affected the in vitro development of caprine and ovine pre‐antral follicles. To improve the efficiency of the culture system, the medium must be replaced every 2 and 6 days for goat and sheep pre‐antral follicles, respectively.  相似文献   
9.
Soil maps were investigated for their potential to indicate the spatial distribution of habitat of the amphibious snail, Fossaria bulimoides, the intermediate host of Fasciola hepatica in Louisiana. On a 760 ha farm adjacent to the Gulf of Mexico, most snail habitats clustered along interfaces of cheniers (relict beaches with sandy soils) with marsh (heavy, gleyed clays). A few small foci occurred on the cheniers above interfaces. Virtually no habitats occupied marsh away from these interfaces, on this or several other farms previously examined. Habitat and soil map overlays were analyzed in a raster-based geographic information system (GIS) with a 10 m pixel size; a model of habitat was generated as bands 50–90 m wide at chenier-marsh interfaces. The model was extrapolated to a 29 000 ha study area and tested on 12 additional farms not adjacent to the Gulf. On these farms, snail surveys were carried out as transects on three strata: waveface (WF, former beachfront) and backslope (BS) chenier-marsh interfaces, and chenier. The perimeters of all habitats encountered were outlined. The interface of marsh with chenier backslopes occupied 5.25% of the area of the farms, but held 21.69% of snail habitat area. Additionally, chenier soils of the Hackberry-Mermentau complex (HM) occupied 12.32% of farm area, but held 61.39% of habitat. Habitat area was related by regression analysis to the proportion of farm consisting of HM soils (r2 = 0.41, P < 0.05).  相似文献   
10.
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