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1.
The vascular features of the distal epiphysis of the radius of 27 foals aged from 3 weeks premature to 120 days postpartum were determined. The limbs were perfused with barium, and the distal radius was sawn into sagittal slabs which were decalcified, cut into thin slices and radiographed. More arteries approached areas of thick cartilage than thin cartilage. In thick cartilage, vessels in a lattice network were observed, and adjacent to these vessels was sinusoidal filling in the epiphyseal subchondral bone, which had a similar pattern to sinusoidal filling in the metaphysis. The sinusoidal filling adjacent to thick cartilage was at the predisposition site for epiphyseal osteomyelitis lesions in foals. This particular type of bone infection occurs commonly in the foal, but much less commonly in other species. The vascular features of the immature epiphysis may account for the predominance of epiphyseal osteomyelitis in the foal.  相似文献   
2.
Effects of adding different concentrations of melatonin (10?7, 10?9 and 10?11 M) to maturation (Experiment 1; Control, IVM  + 10?7, IVM  + 10?9, IVM  + 10?11) and culture media (Experiment 2; Control, IVC  + 10?7, IVC  + 10?9, IVC  + 10?11) were evaluated on in vitro bovine embryonic development. The optimal concentration of melatonin (10?9 M) from Experiments 1–2 was tested in both maturation and/or culture media of Experiment 3 (Control, IVM  + 10?9, IVC  + 10?9, IVM /IVC  + 10?9). In Experiment 1, maturated oocytes from Control and IVM  + 10?9 treatments showed increased glutathione content, mitochondrial membrane potential and percentage of Grade I blastocysts (40.6% and 43%, respectively). In Experiment 2, an increase in the percentage of Grade I blastocysts was detected in IVC  + 10?7 (43.5%; 56.7%) and IVC  + 10?9 (47.4%; 57.4%). Moreover, a lower number and percentage of apoptotic cells in blastocysts were observed in the IVC  + 10?9 group compared to Control (3.8 ± 0.6; 3.6% versus 6.1 ± 0.6; 5.3%). In Experiment 3, the IVC  + 10?9 treatment increased percentage of Grade I blastocysts with a lower number of apoptotic cells compared to IVM /IVC  + 10?9 group (52.6%; 3.0 ± 0.5 versus 46.0%; 5.4 ± 1.0). The IVC  + 10?9 treatment also had a higher mRNA expression of antioxidant gene (SOD 2) compared to the Control, as well as the heat shock protein (HSPB 1) compared to the IVM  + 10?9. Reactive oxygen species production was greater in the IVM /IVC  + 10?9 treatment group. In conclusion, the 10?9 M concentration of melatonin and the in vitro production phase in which it is used directly affected embryonic development and quality.  相似文献   
3.
Development of a scale to evaluate postoperative pain in dogs   总被引:1,自引:0,他引:1  
OBJECTIVE: To design and evaluate a scale for measurement of postoperative pain in dogs. DESIGN: Randomized, blinded, prospective study, with positive- and negative-control groups. ANIMALS: 36 dogs undergoing general anesthesia for ovariohysterectomy and 12 dogs undergoing general anesthesia without surgery. PROCEDURE: A pain assessment scale was developed for dogs, which incorporated physiologic data (heart and respiratory rates) and behavioral responses (response to palpation, activity, mental status, posture, and vocalization). This pain scale was then applied to a study in which dogs were allocated to 2 groups, depending on the type of medication administered (acepromazine maleate only or acepromazine and butorphanol) before induction of general anesthesia. The 36 dogs that had ovariohysterectomy were allocated to 3 groups, members of which received butorphanol, carprofen, or no analgesic after surgery. Dogs were scored for signs of pain and videotaped at 0, 1, 2, 4, 6, 8, 12, and 18 hours after surgery by an assessor who was blinded to the groups. Results were analyzed for significant differences in pain scores for single categories and total pain scores among groups. Video segments were scrambled and then scored by a second external assessor to test the repeatability of the results, using the pain assessment scale. RESULTS: Mean total pain scores were significantly different between the group of dogs that underwent general anesthesia only and each group of dogs that underwent general anesthesia and surgery. Pain scores for the analgesic-treatment groups reflected the known onset and duration of action of the analgesic used. Agreement between the internal and external assessors was excellent and indicated high precision between the 2 assessors for the population of dogs as a whole. CLINICAL IMPLICATIONS: Behavioral and physiologic measurements can be used reliably to evaluate degree of pain in dogs during the postoperative period and their response to analgesics.  相似文献   
4.
OBJECTIVE: To determine the changes in Ca, P, Mg, Na, K, S, Cu, Fe and Zn concentrations of milk during the lactation in pasture-fed Thoroughbred mares and then calculate the dietary mineral requirements of the sucking foal and the lactating mare. PROCEDURE: Milk was sampled on days 1, 3, 7, 14, 21, 28 and at various times between 55 to 65, 85 to 95 and 135 to 150 days after parturition from 21 pasture-fed mares. The concentrations of macro- and micro-elements in the milk were determined by inductively coupled plasma emission spectrometry. RESULTS: Concentrations (mg/L) of these elements were highest in colostrum (Mg 302, Na 561, K 955, S 1035, Cu 0.76, Fe 0.79 and Zn 5.5) except for Ca (1245) and P (895), which where highest on day 7. The mean milk mineral element concentrations (mg/L) over days 55 to 150 were Ca 843, P 543, Mg 47, Na 120, K 590, S 219, Cu 0.19, Fe 0.34 and Zn 2.1. The mean plasma element concentrations (mg/L) over the same period were Ca 120, P 77.1, Mg 17.0, Na 3110, K 168, S 983, Cu 1.1, Fe 1.5 and Zn 0.49. Concentration gradients between plasma and milk were observed and, in the case of Ca, P, Mg, K and Zn, their concentrations in milk were greater than those in plasma, while a reverse situation was observed for Na, S, Cu and Fe. CONCLUSION: With the exception of Ca and P, the highest concentrations of mineral elements were observed in the colostrum. The nursing foal should have access to good pasture or creep feed, because the intakes of Ca, P and Cu from milk may be less than optimum to meet the daily mineral element requirements.  相似文献   
5.
AIM: To measure the nutritive value of pasture in terms of digestible energy (DE) intake (DEI) and dry matter (DM) digestibility, and to determine the apparent absorption of macroelements in lactating Thoroughbred mares grazed on pasture. METHODS: DM intake (DMI) and DEI were determined from daily faecal DM output measured in grazing mares, divided by the DM indigestible fraction (1-digestible DM), measured in a digestibility trial using pasture-fed mares. Eight lactating mares and their foals, that had a mean age of 40 days, were grazed separately on 50x100 m areas of pasture and daily faecal DM outputs were recorded for 8 days. Five mares and their foals were then placed in individual bare 20x20 m corrals containing custom-made feeding stations for 14 days to determine the indigestible DM fraction. DM, gross energy content, crude protein (CP), soluble carbohydrate, acid detergent fibre (ADF), neutral detergent fibre (NDF), lipid, and macroelement composition of the pasture offered and faeces were determined and their digestibility and/or apparent absorption calculated. RESULTS: DM digestibility of the pasture was 0.6 and the DMI and DEI of a grazing 560 kg mare in early lactation nursing a foal growing at 1.34 kg/day was 13.6 (SE 0.8) kg/day and 146.9 (SE 8.4) MJ DE/day, respectively. Apparent absorptions of the macroelements measured were: Ca 0.75, P 0.43, Mg 0.63, Na 0.78, and K 0.72. CONCLUSIONS: Good quality ryegrass-white clover pasture that had a DE content of 10.8 MJ/kg DM, and a macroelement composition (g/kg) of Ca 3.33, P 3.0, Mg 1.67, Na 1.67, and K 24.2, will provide adequate DMI, DEI, and macroelement intake to lactating Thoroughbred mares.  相似文献   
6.
Objective To evaluate standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals, as techniques for obtaining tissue for assessment of copper status. The techniques were evaluated with respect to ease of use and effect on the animal.
Procedure Twenty of 24 Thoroughbred mares and 21 of their foals were biopsied. The animals were part of a larger study of the effect of copper supplementation on copper status and the prevalence of developmental orthopaedic disease. Livers were also collected from unrelated horses and sampled to investigate the variability in the distribution of copper in liver tissue.
Result The biopsy technique caused no lasting effect on the mares, but there was an increased risk of viscus penetration associated with taking multiple biopsy cores. The use of ultrasonography to scan the target area for the liver identified four cases that were not appropriate candidates for liver biopsy, because of large intestine being located in the biopsy area. In the foals there were no serious postoperative adverse effects, nor was there any evidence of problems caused by the procedure when the abdomen was examined post-mortem at 5 months of age. In livers collected to investigate the variability of copper concentration, copper appeared to be relatively evenly distributed through the liver.
Conclusion Standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals are convenient procedures for obtaining liver tissue for assessing copper status in horses. The use of ultrasound to identify liver tissue is recommended, especially in older mares.  相似文献   
7.
8.
Two cases of Rhodococcus equl infection in foals are described, in which osteomyelitis was a feature. Because rhodococcal infection is usually low grade and chronic, and because the signs of early metaphysitis can be subtle, any articular or periarticular swelling in a foal from a farm with a history of rhodococcosis should be strongly suspected to be associated with R equl until proven otherwise.  相似文献   
9.
Eighty-three calves with a complicated umbilical hernia were included in a randomised prospective study. The frequency of wound infection was compared in two groups. The first group received antibiotics for one day, the second group for four days. The infection rate in calves receiving antibiotics for one day was 25 per cent compared with 8 per cent in calves treated for four days (P less than 0.05). Male calves were more susceptible to infection than female calves.  相似文献   
10.
Plasma disposition, protein binding, urinary recovery, and renal clearance of sulfamethazine (SMZ), sulfamerazine (SMR), and sulfadiazine (SDZ) and their N4-acetyl and hydroxy derivatives were studied in 4 horses in a crossover trial. The plasma concentration-time curves of the metabolites paralleled those of the parent drug in the elimination phase. Sulfamethazine and SMR were extensively metabolized. In plasma and urine, the main metabolite of the 3 sulfonamides tested was the 5-hydroxypyrimidine derivative, which was highly glucuronidated. Difference in elimination half-life of SMZ, SMR, and SDZ could be related to difference in metabolism and renal clearance values. Metabolism speeds drug elimination, producing compounds with higher renal clearance values than those of the parent drug. Methyl substitution in the pyrimidine side chain increased hydroxylation of the parent drug, but prolonged the persistence of the sulfonamides studied in the body. The high concentration of N4-acetyl and hydroxy metabolites of SMZ and SMR in plasma and urine decreased the potential antibacterial activity of the parent drugs. Sulfadiazine was less metabolized, and microbiologically determined SDZ concentrations in plasma and urine were slightly lower than those measured by high-performance liquid chromatography.  相似文献   
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