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111.
The purpose of this study was to evaluate the effect of cooling ovarian tissue on pig pre-antral follicles. Ovaries were maintained in saline solution (0.9%) at 4 or 20 degrees C for 6, 12 or 18 h. After storage, pre-antral follicles were morphologically evaluated. While primordial follicles were not affected by the storage, the percentage of morphologically normal growing follicles was significantly reduced in ovarian tissue stored at 20 degrees C for 12 or 18 h. To test the viability of stored follicles, growing follicles isolated from ovaries stored at 4 degrees C for 18 h and at 20 degrees C for 6 h were cultured for 3 days. Follicles stored in either condition presented the same growth pattern in vitro as fresh follicles. We conclude that storage of pig ovaries at 4 degrees C for up to 18 h or at 20 degrees C for up to 6 h does not affect the morphology of growing follicles or their ability to grow in vitro.  相似文献   
112.
Due to extreme weather conditions, a flock of outwintered Icelandic horses had to manage for several days on snow as the source of free water. They were fed grass silage ad lib, and any change in feed consumption was not observed. After nine days, blood samples were taken and analysed for plasma osmolality, they were subjected to a simple clinical examination, and offered drinking water. Osmolality levels were within normal limits and mean value did not differ significantly from samples which previously were taken of the same individuals. The general condition of the horses was normal, with no signs of clinical dehydration or disease. The horses showed very little interest for the offered drinking water. This suggests that in cold winter weather, horses being fed grass silage and adjusted to eat snow, can manage for several days with snow substituting liquid water without their physiology and welfare being challenged.  相似文献   
113.
AIMS: To investigate the production responses and cost-benefit of administering a controlled-release anthelmintic capsule (CRC) to pregnant yearling ewes prior to lambing.

METHODS: Yearling ewes from two commercial sheep flocks (A, n=489; B, n=248) in the North Island of New Zealand were enrolled in the study. Prior to lambing, CRC containing albendazole and abamectin were administered to half the ewes while the other half remained untreated. Ewe liveweights and body condition scores were measured prior to lambing, at weaning and, for Flock B, prior to subsequent mating. Lambs were matched to dams shortly after birth and the weight and number of lamb weaned per ewe were determined. A cost-benefit analysis was undertaken for Flock B considering the increased weight of lamb weaned per ewe, and the weight of ewes at the next mating and the benefit in terms of lambs born.

RESULTS: The mean weight at weaning of treated ewes was greater for treated than untreated ewes by 2.76 (95% CI 0.64–4.88)?kg in Flock A (p<0.001) and 2.35 (95% CI ?0.41–5.12)?kg in Flock B (p=0.003); the weight of lamb weaned per ewe was greater for treated than untreated ewes by 1.43 (95% CI ?0.71 to –3.49)?kg in Flock A (p=0.041) and 3.97 (95% CI 1.59–6.37)?kg in Flock B (p<0.001), and ewe liveweight prior to subsequent mating was greater for treated than untreated ewes in Flock B by 4.60 (95% CI 3.6–5.6)?kg (p<0.001). There was no difference in the percentage of lambs reared to weaning between treated and untreated ewes in either flock (p>0.8). The overall cost-benefit of treatment for Flock B was NZ$9.44 per treated ewe.

CONCLUSIONS AND CLINICAL RELEVANCE: Pre-lambing CRC administration to yearling ewes resulted in increased ewe weaning weights and weight of lamb weaned in both the flocks studied. There was an economic benefit in the one flock where this was assessed.  相似文献   

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115.
Objective To determine the effect of a long-acting local anaesthetic on the plasma cortisol response in calves dehorned using a scoop.
Design A physiological study with controls.
Procedure Seventy female calves, 3 to 4 months old, were divided into seven groups and dehorned by scoop with or without a long acting local anaesthetic (bupivacaine) which provides local anaesthesia for 3 to 4 h. In some treatment groups the local anaesthetic was given a second time, after 4 h, to give 8 h of anaesthesia. Blood samples were taken before and for 9 h after treatment and plasma cortisol concentrations were measured.
Results Scoop dehorning caused a marked rise in plasma cortisol concentration, which returned to pre-dehorning values after 7 h. The cortisol concentrations of calves given bupiva-caine were similar to those of control animals for 4 h after dehorning, but then a significant and protracted rise occurred, with concentrations returning to pretreatment values at about 9 h after dehorning. In calves given a second treatment of bupivacaine 4 h after dehorning, the plasma cortisol concentration remained similar to control values for 8 h after dehorning but then increased sharply.
Conclusions During its period of activity long-acting local anaesthetic prevented the rise usually seen after scoop dehorning in plasma cortisol concentrations; by inference it also alleviated the pain-induced distress caused by this procedure. However, when its effects had worn off the plasma cortisol values rose sharply indicating that animals still experienced pain-induced distress despite local anaesthetic being administered.  相似文献   
116.

Objective

To compare the effects of two concentrations of oxygen delivered to the anaesthetic breathing circuit on oxygenation in mechanically ventilated horses anaesthetised with isoflurane and positioned in dorsal or lateral recumbency.

Methods

Selected respiratory parameters and blood lactate were measured and oxygenation indices calculated, before and during general anaesthesia, in 24 laterally or dorsally recumbent horses. Horses were randomly assigned to receive 100% or 60% oxygen during anaesthesia. All horses were anaesthetised using the same protocol and intermittent positive pressure ventilation (IPPV) was commenced immediately following anaesthetic induction and endotracheal intubation. Arterial blood gas analysis was performed and oxygenation indices calculated before premedication, immediately after induction, at 10 and 45 min after the commencement of mechanical ventilation, and in recovery.

Results

During anaesthesia, the arterial partial pressure of oxygen was adequate in all horses, regardless of position of recumbency or the concentration of oxygen provided. At 10 and 45 min after commencing IPPV, the arterial partial pressure of oxygen was lower in horses in dorsal recumbency compared with those in lateral recumbency, irrespective of the concentration of oxygen supplied. Based on oxygenation indices, pulmonary function during general anaesthesia in horses placed in dorsal recumbency was more compromised than in horses in lateral recumbency, irrespective of the concentration of oxygen provided.

Conclusion

During general anaesthesia, using oxygen at a concentration of 60% instead of 100% maintains adequate arterial oxygenation in horses in dorsal or lateral recumbency. However, it will not reduce pulmonary function abnormalities induced by anaesthesia and recumbency.  相似文献   
117.
118.
The aim of the study was to investigate the effect of the antioxidant astaxanthin on boar semen. Twenty ejaculates from 10 boars (two ejaculates/boar) were extended and split in three groups: semen control (SC), solvent control (C; semen with dimethyl sulfoxide, the diluent of astaxanthin) and semen with astaxanthin (A) in concentration 0.5 μmol/L. Sperm quality parameters (motility and kinetics, morphology, viability, functional integrity of sperm plasma membrane by Hypo‐Osmotic Swelling Test [HOST] and DNA integrity) were assessed at 0, 24 and 48 hr of storage at 17°C (experiment I), before (0 hr) and after (1 hr) of sperm thermal resistance assay at 37°C (experiment II) and finally before (0 hr) and after (1 hr) sperm in vitro incubation (38.5°C, 5% CO2, maximum humidity [experiment III]). In experiment I, group A performed overall better than group SC and as a tendency better than group C regarding viability. Total motility, rapid spermatozoa and HOST remained constant across time in group A, whereas they decreased in the remaining groups. In experiment II, regarding motility and viability, group A displayed better results across time than the other two groups. In experiment III, viability and total motility decreased in groups SC and C, while in group A, these parameters were not significantly different between the examination time points. In conclusion, astaxanthin has a beneficial and protective effect on boar semen quality under the investigated conditions.  相似文献   
119.
120.
To date, the only repeatable method to select spermatozoa for chromosomal sex is the Beltsville sorting technology using flow cytometry. Improvement of this technology in the equine species requires increasing awareness of the modifications that the sorting procedure induces on sperm intactness. Oxidative stress is regarded as the major damaging phenomenon, and increasing evidence regards handling of spermatozoa – including sex sorting – as basic ground for oxidative damage. The aim of this study was to disclose whether the flow cytometric sorting procedure increases the production of reactive oxygen species (ROS), and to identify if ROS production relates to DNA damage in sorted spermatozoa using specific flow cytometry‐based assays. After sorting, oxidative stress increased from 26% to 33% in pre‐ and post‐incubation controls, to 46% after sex sorting (p < 0.05). Proportions of DNA fragmentation index post‐sorting were approximately 10% higher (31.3%); an effect apparently conduced via oxidative DNA damage as revealed by the oxyDNA assay. The probable origin of this increased oxidative stress owes the removal of enough seminal plasma due to the unphysiological sperm extension, alongside a deleterious effect of high pressure on mitochondria during the sorting procedure.  相似文献   
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