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131.
Acanthomatous ameloblastoma (AA) is a benign gingival tumour that often invades bone. This retrospective study evaluated the efficacy of intralesional (IL) bleomycin as a treatment for AA. Six dogs received weekly or bimonthly IL bleomycin injections (dose range, 10–20 U m?2). A seventh dog presented with advanced, nonresectable AA was treated palliatively. One to sixteen treatments were administered (median, 5). Six of the seven dogs had a complete response within 4 months from initial IL injection (median, 1.5 months), whereas the palliative case had approximately 25% decrease in tumour volume 14 days from initial injection. Local recurrence was not observed during the study period, with a median follow‐up time of 842 days. Adverse effects were limited to wound formation with bone exposure (n = 4), mild tissue reactions (n = 3), local swelling (n = 2) and local infection (n = 1). The conclusions of this study show IL bleomycin is an effective treatment for canines with AA.  相似文献   
132.
The inbred SLA miniature pig is a unique animal model developed for organ transplantation studies and pre‐clinical experimental purposes. Reported oestrous synchronization and superovulation treatments were examined in two SLA haplotypes (AA and DD) to allow collection of embryos for both practical embryo transfer and experimental technologies from a closed breeding colony. Pre‐puberal miniature pigs were poor responders to oestrous synchronization treatments, while post‐puberal sows were equivalent to commercial sows. Following superovulation, the ovulation number (corpora .hemorrhagica) was higher (p < 0.05) in the cycling sows when compared with non‐cycling sows. Ovulations were equivalent to commercial pre‐puberal gilts and non‐cycling sows (p > 0.05). No difference in ovulation number between haplotypes was observed, which differs from the previous report (DD>AA). Collection of zygotes for pronuclear injection was the highest in the non‐cycling post‐puberal miniature pig group (p < 0.05), although significantly lower when compared with the commercial pig treatment groups (p < 0.05). The incidence of cystic endometrial hyperplasia in our colony was equivalent to rates observed in commercial pigs. Pronuclear visualization following centrifugation was the highest in the non‐cycling miniature sow group and approximates to about 25% of ovulations and about half the rate observed in the commercial pigs (50%). Miniature pig embryos transferred between SLA haplotypes and transfer of DD embryos to commercial pigs resulted in live births at a higher efficiency than previously reported. This study demonstrates the feasibility of undertaking assisted reproductive technologies in a closed breeding colony of inbred SLA miniature pigs without compromise to the breeding programmes.  相似文献   
133.
High stress levels in horses during sporting events can influence the animal’s performance in competitions as well as their welfare. This study investigated the use of infrared thermography (IRT) measurement as a rapid, noninvasive, and accurate method for stress assessment in horses during sport competitions and compared IRT with a commonly used physiological method used for stress assessment and salivary cortisol. IRT and salivary cortisol responses were measured 3 hours before the competition, immediately following the competition, and 3 hours after the competition, each day during the 3 days of a show jumping event. Salivary cortisol values ranged from −0.11 ± 4.51 ng/mL in 5-year-old animals to 1.10 ± 2.20 ng/mL in 4-year-old animals, whereas eye temperature values ranged from 35.84 ± 1.16°C in 6-year-old animals to 36.08 ± 1.11°C in 5-year-old animals. The results obtained suggested that IRT measurements constitute an effective method for detecting stress in horses subjected to the acute events of show jumping.  相似文献   
134.
Bovine respiratory disease complex (BRD) causes considerable economic loss and biosecurity cost to the beef industry globally and also results in significant degradation to the welfare of affected animals. The successful treatment of this disease depends on the early, timely and cost effective identification of affected animals. The objective of the present study was to investigate the use of an automated, RFID driven, noninvasive infrared thermography technology to determine BRD in cattle. Sixty-five calves averaging 220 kg were exposed to standard industry practices of transport and auction. The animals were monitored for BRD using conventional biometric signs for clinical scores, core temperatures, haematology, serum cortisol and infrared thermal values over 3 weeks. The data collected demonstrated that true positive animals for BRD based on a gold standard including core temperature, clinical score, white blood cell number and neutrophil/lymphocyte ratio displayed higher peak infrared thermal values of 35.7±0.35 °C compared to true negative animals 34.9±0.22 °C (P<0.01). The study also demonstrated that such biometric data can be non-invasively and automatically collected based on a system developed around the animal's water station. It is concluded that the deployment of such systems in the cattle industry would aid animal managers and practitioners in the identification and management of BRD in cattle populations.  相似文献   
135.
The anthropogenic effects of Antarctic refuge buildings and research stations on the surrounding soils are scarcely investigated, especially when the structures are small-sized, and sporadically used or visited. The Coppermine Peninsula (Robert Island, South Shetland Islands archipelago) possesses one of the richest flora in Antarctica, being classified as an Antarctic Specially Protected Area (ASPA). There, a small refuge (Luis Risopatrón) has been seasonally occupied for scientific purposes since 1957, although no studies on the anthropic disturbances in the surroundings soils are reported. The aim of this study was the determination of the potentially toxic metals (Cd, Cr, Cu, Mn, Ni, Pb, V, and Zn) mass fractions in surface soils (n?=?40) collected at the surroundings of the Luis Risopatrón refuge. Enrichment factors (EF) and geoaccumulation index (I geo) were also calculated, using Zr as the reference element, in order to evaluate the anthropogenic impacts of these small buildings in the studied area. The main contaminants were Pb and Zn, which presented EF and I geo values ranging from 1.0 to 18.3 and from ?1.8 to 3.5. The mass fractions of these elements determined after an aqua regia extraction varied from 5.4 to 102 mg kg?1 Pb and from 43 to 210 mg kg?1 Zn. These results highlight that a small refuge can show environmental disturbance from low to moderate, with few hotspots with heavily contaminated soils. Environmental monitoring strategy for similar refuges anywhere in Antarctica is recommended.  相似文献   
136.
On November 5, 2015, after the collapse of the Fundão tailings dam, a massive amount of iron mine waste was released into the Doce River system in southeast Brazil. The aim of our study was to determine the mass fractions of potentially toxic elements in soil affected by the deposition of material by the waste wave. A preliminary screening was performed with portable X-ray fluorescence spectrometry (PXRF) and principal component analysis (PCA). The EPA 3050B method was further applied to digest the samples for quantitative determination of As, Ba, Cr, Cu, Mn, Ni, Pb, V, and Zn by inductively coupled plasma mass spectrometry. PCA was useful to classify the mine waste samples based on the Fe signal from the PXRF spectra, in spite of the heterogeneous nature of the material discharged into the Doce River system. The anomalous levels of As (up to 164 mg kg?1) and Mn (as high as 2410 mg kg?1) found in some mine waste and affected soil samples are within the background ranges typically observed in the soils of the Iron Quadrangle region. The toxicity characteristic leaching procedure shows no evidence of hazards regarding As, but a high natural background level of Mn was found in the mobile fraction. This preliminary environmental assessment highlights the importance of evaluation of long-term effects on soil directly impacted, as well as on the aquatic biota of the Doce River system and adjacent coastal environment given the large affected area, which includes regions with varying background levels of toxic elements.  相似文献   
137.
To achieve a standardized number of spermatozoa in the final AI dose, varying amounts of extender fluid with a fixed concentration of antimicrobial substances are currently added to boar ejaculates. This practice ignores the different degrees of dilution of the antimicrobials in the end product. In calculating the final concentration of gentamicin in AI doses from 27,538 processed boar ejaculates, we demonstrated varying gentamicin concentrations in the resultant extended boar semen samples. The median concentration was 220.37 mg/L. In 25 of the samples (0.09%), the gentamicin concentration fell below 5 mg/L, which is close to or below the epidemiological cut‐off value for many bacteria. We calculated the minimum inhibitory concentration of gentamicin for bacteria isolated from raw and extended ejaculates. Five of the isolates from extended ejaculates exceeded the maximum test concentration of 512 mg/L. As a result, we are presenting an alternative method of boar semen preservation whereby a particular combination of gentamicin concentrate and antibiotic‐free extender is incorporated that standardizes the antibiotic concentration in the diluted semen. The addition of standardized antibiotic concentrations did not negatively affect sperm quality when compared to the use of ready‐to‐use extenders. In conclusion, an end volume‐based and standardized addition of gentamicin to boar ejaculates can be a helpful alternative to prevent insufficient dosage of antibiotics in liquid preserved boar semen without affecting semen quality.  相似文献   
138.
We investigated the effect of body protein mass at parturition and different degrees of body protein loss in lactation on sow performance. In a 2 x 2 factorial arrangement, 77 Genex gilts were fed to achieve either a standard or high body mass at parturition and to lose either a moderate (MPL) or high (HPL) amount of protein in lactation. Pregnant gilts were fed either 24.4 MJ of ME, 266 g of CP, and 11 g of lysine/d or 34.0 MJ of ME, 436 g of CP, and 20 g of lysine/d resulting in divergent (P < 0.01) live weights (165 vs. 193 kg) and calculated protein masses (24.3 vs. 30.0 kg) and slightly different backfat depths (20.0 vs. 22.8 mm; P < 0.05) at parturition. Diets fed during lactation were formulated to deliver 731 g of CP and 37 g of lysine/d or 416 g of CP and 22 g of lysine/d to induce differential body protein mobilization. Sows were slaughtered at weaning (d 26), and the weight of the organs and the lean, fat, and bone in five primal cuts was measured. The external diameter of the eight largest follicles on each ovary was recorded, and the follicular fluid from these follicles was collected, weighed, and analyzed for estradiol. Losses in lactational live weight (26 vs. 20 kg; P < 0.01) and calculated protein mass (17.8 vs. 10.7%; P < 0.001) were greater, and the carcass lean mass at weaning was 10% lighter (P < 0.05) in HPL sows. Backfat (5.1 +/- 0.8 mm; P = 0.29) and calculated fat mass (25.8 +/- 1.5%; P = 0.84) losses did not differ between treatments. Both sow body mass (P < 0.05) and lactation protein loss (P < 0.01) affected litter growth rate. Litter growth rate decreased (P < 0.05) at the end of lactation in HPL sows once these sows had lost 10 to 12% of their calculated protein mass. Ovarian follicular development was most advanced in high body mass sows that lost the least protein; these sows had the heaviest (P < 0.05) uterine weight and highest (P < 0.05) follicular fluid estradiol concentration. Follicular development was least advanced in standard body mass sows that lost the most protein. These sows had the lowest (P < 0.05) muscle:bone ratio at weaning and likely lost the largest proportion of their muscle mass compared with the other treatments. In conclusion, ovarian function at weaning and litter performance was higher in high body mass sows and in sows that lost the least protein in lactation, suggesting that a larger lean mass may delay the onset of a decrease in performance in sows that lose protein in lactation.  相似文献   
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140.
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