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S(+) ketamine, one of the two enantiomers of racemic ketamine, is a phencyclidine derivative that induces amnesia and analgesia. Its activity is related to blockade of NMDA receptors and some opioid action. We compared anesthetic induction and recovery quality with S(+) ketamine in combination with diazepam or midazolam in 10 dogs (ASA 1) admitted for elective surgery. After all clinical examinations, the dogs were separated into two groups (G I and G II). All animals received acepromazine (0.1 mg kg?1) and fentanyl (5 µg kg?1) IM, 20 minutes before induction with S(+) ketamine (6 mg kg?1) and diazepam (0.5 mg kg?1) IV (G I) or midazolam 0.2 mg kg?1 (G II) IV. The doses of diazepam and midazolam were chosen according to the literature. All dogs were intubated and then maintained with halothane in oxygen at a vaporizer setting sufficient to maintain surgical anesthesia. Quality of induction, time needed for intubation, heart rate, respiratory rate, SpO2, time to extubation, and quality of recovery were evaluated. The results were analyzed by Student's t‐test. Smooth induction and recovery were observed in all animals. The time to intubation was 45 ± 20 (GI) and 25 ± 6 seconds (GII), HR was 122 ± 12 (GI) and 125 ± 7 beats minute?1 (GII), RR was 17 ± 2 (GI) and 21 ± 3 breaths minute?1 (GII), SpO2 was 96 ± 2 (GI) and 94 ± 1% (GII), time to extubation was 7 ± 3 (GI) and 4 ± 1 minutes (GII). No statistical differences were found in analyses, although time to intubation was less in GII. The results suggested that both combinations could be used safely for anesthetic induction in healthy dogs.  相似文献   
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Maternal diet prior to mating has an effect on reproductive performance. We analysed the effect of maternal dietary restriction during rearing on reproductive performance, the embryo development and foetal growth. Females were categorized in two groups: (i) does with ad libitum access to feed or (ii) restricted. Two experiments were performed: (i) after 1 month, receptive females from both experimental groups were artificially inseminated and the reproductive performance was recorded during three reproductive cycles; at the first insemination, the body weight and perirenal fat thickness were recorded, and (ii) females from both experimental groups were inseminated, and 24 h later, embryos were recovered and transferred to recipient females from a maternal line. Later, embryonic implantation was assessed at day 14 by laparoscopy and foetal growth was monitored by ultrasound examination. In experiment 1, no differences in kindling rate was found, but prolificacy was showed to be higher in ad libitum does, which also were heavier than restricted ones. In experiment 2, no differences among does either in body weight, in perirenal fat thickness or in reproductive performance (ovulation rate and embryo recovery rate) were related to differences in feed intake. However, despite similar embryonic implantation losses, embryos from restricted females demonstrated higher foetal and gestational losses. Embryos from restricted does presented lower foetal growth than embryos from ad libitum does. Therefore, our results demonstrated that nutrition before first conception in a rabbit line selected for growth rate may impact on the embryo and results in a disturbance in gestational losses and foetal growth over all reproductive life.  相似文献   
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Equine in vitro fertilization (IVF) is still inconsistent. In the present work, we studied how modified Whitten's (MW) medium and Tissue Culture Medium 199 (TCM) added with Foetal Bovine Serum (FBS; 10% v/v) or Bovine Serum Albumin (BSA; 7 mg/ml) affected equine gametes to subsequently run IVF trials. Compact (Cp) and expanded (Ex) cumuli equine oocytes were matured and placed in TCM or MW supplemented with BSA or FBS for 18–20 h (no sperm added). In Ex oocytes, TCM‐199 added with FBS or BSA resulted in higher metaphase II (MII) rates (75.7% and 62.7%, respectively) than MW added with BSA (54%) or FBS (52.2%; p < 0.05); this was not observed for Cp oocytes. Equine sperm were capacitated in the same media at 10 × 106 sperm/ml for 4 h at 37°C; total motility and protein tyrosine phosphorylation (PY) were evaluated. While motility remained unchanged, TCM or MW added with FBS enhanced the number of sperm showing PY‐stained tails (25 ± 4.8% and 31 ± 6.6%; mean ± SEM, respectively) over BSA supplemented media (3 ± 1.2% and 11.7 ± 1.1%) for TCM and MW (p < 0.05). In view of the previous results, sperm were capacitated in TCM + FBS and MW + BSA (control); IVF trials were run in the same media supplemented with 200 ng/ml of progesterone, but no fertilization occurred. Our results show that TCM + FBS enhances Ex equine oocyte's meiotic competence over MW + BSA and TCM or MW added with FBS successfully induce equine PY over media supplemented with BSA.  相似文献   
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Objective To investigate the efficacy of ivermectin in an intraruminal controlled-release capsule (CRC) against blowfly strike.
Design Pen and field trials with controls.
Animals Pen studies: Two breech strike trials involving 60 Romney and 60 Merino sheep. One body strike trial using 100 Merino sheep.
Field trials: Eight trials in New Zealand used 1000 Romney and Romney-cross sheep. Fifty Merino lambs in one trial in Australia.
Procedure Pen studies: Sheep were allocated to two equal groups. One was not treated, the other sheep received a CRC that delivered ivermectin at 20 μg/kg/day for 100 days. In the breech strike trials, each animal was given an oral laxative 2 days before exposure to adult Lucilia cuprina . In the body-strike trial, the sheep sheep were kept wet to increase susceptibility prior to the release of blowflies.
Field trials: Fifty or 200 sheep allocated to equal groups of nontreated or treated with the CRC and grazed at pasture exposed to natural blowfly challenge.
Results Pen studies: Breech strikes developed in 24 of 60 controls but in none of 60 CRC-treated sheep. There was a 35% reduction in the number of CRC-treated sheep struck on the body.
Field trials: The average number of breech strikes in CRC-treated sheep was reduced by 86% (P < 0.001). The number of body strikes in the treated groups was a reduced by 27% (P < 0.05).
Conclusion The ivermectin CRC is a useful aid in controlling breech strike, but provides only moderate reduction in the incidence of body strike.  相似文献   
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Objective To confirm the efficacy of ivermectin released from a controlled-release capsule administered to young sheep and to breeding ewes under field conditions. Design Randomised field trials. Procedure In each of ten field trials 25 weaned lambs were treated with ivermectin controlled-release capsules and 25 remained untreated. Eight similar field trials were conducted using adult ewes. Efficacy against infections of gastrointestinal nematodes was assessed by faecal egg counts and faecal larval culture. Body weights were recorded and faecal soiling of the breech wool (dags) was assessed. Results Nematode faecal egg counts in the two groups were not different (P = 0.13) before treatment in the weaner trials or before treatment in the ewe trials (P = 0.49), but thereafter eggs in the untreated sheep persisted, whereas counts in sheep given capsules were negligible (P ≤ 0.01). In the weaner trials, dag scores for the two groups were not different at the start of the trials (P = 0.18) but at the end, untreated sheep had significantly more dags (P = 0.04) than treated sheep. In the ewe trials, dag scores remained low in both groups. Weaners treated with the capsule gained 1.4 kg (95% CL: 0.7, 3.1) more weight over the 16 week trial period compared to untreated weaners (P = 0.01). Both groups of ewes lost weight as a result of parturition but the mean loss by week 16 was greater for untreated (3.7 kg) (95% CL: -5.1,-2.2) than for treated ewes (1.8 kg) (95% CL: -3.3, -0.4). The mean change in ewe body weight for the two groups was however not significant (P = 0.07). Differentiation of nematode larvae recovered from cultures of faeces from untreated animals indicated that the capsules were effective against the common parasites of sheep. Conclusion The capsule was efficacious against gastrointestinal nematodes judging from faecal egg counts. It has the potential to significantly reduce contamination of pasture with nematode eggs. Treated weaners had less dags for 16 weeks and gained more weight than untreated weaners.  相似文献   
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This study aims to assess the efficiency of in vivo oocyte and embryo recovery after a recombinant human FSH (rhFSH) treatment in rabbit does. Females were distributed in two experimental groups: donor does were treated with rhFSH (superovulation group) for 3 days prior to artificial insemination (embryo recovery) or ovulation induction (oocyte recovery) and does without treatment remained as the control group. Mature oocytes or embryos were collected with the laparoscopy technique 16 h after ovulation induction (oocytes) or 72 h after artificial insemination (embryos). Up to four recoveries were performed with each doe. Recovery efficiencies differed significantly between embryos (84%) and oocytes (58%). Yet, the recovery rates for the superovulation and control groups did not differ. The rhFSH group was associated with a significant increase (p < 0.05) in the number of oocytes and embryos recovered in comparison with the control group (10.2 ± 1.0 and 14.3 ± 1.2 vs 6.0 ± 2.7 and 8.4 ± 2.3 for oocytes and embryos, respectively). Results from this study indicate that repeated in vivo oocyte and embryo recovery from rhFSH superovulated does maximizes the number of oocytes or embryos collected from the same female.  相似文献   
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