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1.
Manipulated Mouse Embryos as Bioassay System for Water Quality Control   总被引:1,自引:0,他引:1  
Mouse pronuclear stage embryos with intact slit zona pellucida (manipulated) were cultured in vitro until the hatched blastocyst stage in simplex optimized medium with higher K+ concentration (KSOM) prepared with three different water types: tap, deionized reverse osmosis (D‐O) water and Milli‐Q system (M‐Q) water. The culture media were supplemented with or without protein and ethylenediaminetetraacetic acid (EDTA, disodium salt). The rates of hatched blastocysts were significantly affected (p < 0.01) by micromanipulation, protein supplement and water source. The water source has no influence (p > 0.05) on development in EDTA‐supplemented protein‐free culture media, whereas in EDTA‐ and protein‐free culture media, the water quality significantly (p < 0.001) affected the rates of development, with higher rates in media prepared with M‐Q water. The micromanipulated embryos showed higher sensitivity to the water quality (p < 0.01). It worth mentioning that the rates of hatched blastocysts in protein‐free culture media were very low (0–7.5%). Furthermore, the three different water types were analysed by measuring the electrical conductivity, inorganic ions, total organic carbon and endotoxins to evaluate the purity. M‐Q water showed the lowest levels of inorganic ion, total organic carbon and endotoxin concentrations. We concluded that manipulated mouse embryos are good system to evaluate the quality of water used in biological system.  相似文献   
2.
To assess the effect of the angiotensin‐converting enzyme (ACE) inhibition on the efficiency of the fixed‐time artificial insemination (TAI), 69 goats were divided randomly into two groups: enalapril (n = 35) and control (n = 34). In the experiment, all animals underwent the protocol of fixed‐time artificial insemination for 12 days. Enalapril group received enalapril maleate dissolved in saline (Enalapril, Lab Teuto Ltda) subcutaneously at the following doses: 0.2 mg/kg/day in D0‐D2; 0.3 mg/kg/day in D3‐D6 and 0.4 mg/kg/day in D7‐D11. The control group received the corresponding volume of 0.9% saline solution. We performed a single insemination 36 hr after sponge removal using frozen semen from two adult male goats with recognized fertility. The ultrasound pregnancy diagnosis was 30 days after the artificial insemination (AI). There was significant increase in pregnancy rates and twinning as well as a decrease in foetal loss in animals receiving enalapril (p < .01). The use of ACE inhibitors during the TAI protocol was shown to be a promising alternative to increase the efficiency of such reproductive biotechnology.  相似文献   
3.
The aim of this study was to evaluate the reproductive performance of three parities of gilts treated or not treated with gonadotropin to induce puberty. Sixty gilts received 600 IU of equine chorionic gonadotropin (eCG) followed by 2.5 mg of porcine luteinizing hormone (LH) 72 h later. Fifty‐nine other gilts were exposed only to a mature boar for 15 min twice daily. Artificial insemination (AI) was performed at 0, 12 and 24 h after the detection of oestrus, and gestation was confirmed by ultrasound after 35 days. Sows were inseminated at the first post‐weaning oestrus. The total numbers of piglets born, piglets born alive, stillborn, mummified foetuses, as well as pregnancy and farrowing rates were evaluated for each of the three parities. Culling rates, farrowing intervals and weaning‐to‐oestrous intervals (WEI) were also analysed. Mean age at puberty and oestrous manifestation were not significantly different between treatments (p = 0.0639; 179.20 ± 17.52 compared with 173.96 ± 16.94, 91.66% compared with 94.92%) across the experimental period. However, females that underwent puberty induction showed modest increases both in the number of total pigs born and in the number of piglets born alive. In conclusion, puberty induction through exogenous gonadotropin administration in field conditions did not induce a more concentrated first oestrous manifestation, but trended to a modest increase in the number of pigs born alive in the first parity and a reduced culling rate during the first gestation.  相似文献   
4.
Two experiments were conducted to test the following hypotheses: 1) exposure of beef heifers to sterile bulls increases the proportion of heifers attaining puberty by 14 mo of age and 2) rate of growth interacts with bull exposure to influence age at puberty in beef heifers. In Exp. I, heifers were assigned to one of two treatments: 1) heifers were exposed to bulls (BE; approximately 70-d period of exposure) or 2) heifers were isolated from bulls (NE) and served as controls. In Exp. II, heifers were assigned to either BE or NE treatments (175-d period of exposure to bulls) and were fed to gain at a moderate (MG; .6 kg/d) or high (HG; .8 kg/d) growth rate. Blood samples were collected twice weekly to determine concentrations of progesterone indicative of onset of corpus luteum function and puberty. In Exp. I a greater (P less than .05) proportion of heifers receiving the BE treatment than of heifers receiving the NE treatment initiated corpus luteum function by 14 mo of age. In Exp. II, there was a bull exposure x growth rate interaction (P less than .05). The effect of bull exposure was greater within the HG groups than within the MG groups. However, heifers fed to attain a moderate or high growth rate and exposed to bulls attained puberty at younger ages than heifers not exposed to bulls and fed to attain a moderate or high growth rate. Mean ages at puberty were 375, 422, 428, and 449 (pooled SEM = 8.6) d for heifers in the BE-HG, BE-MG, NE-HG, and NE-MG groups, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
5.
6.
Whole raw soybeans (SB), wet corn gluten feed (WCGF), and corn dried distillers grains (DDG) are sources of protein in heifer development rations. The objectives of this study were to compare puberty status before synchronization of estrus, response to synchronization, and AI and final pregnancy rates in heifers developed on diets containing SB, WCGF, or DDG that were formulated to be similar in energy and CP. These ingredients vary substantially in fat content, which may affect reproductive performance. Rate of gain during the feeding period and post-AI performance were also compared. In a preliminary experiment, 104 crossbred heifers were fed diets containing either 1.25 kg of SB/d or 2.0 kg of WCGF/d for 110 d (DM basis), beginning at 10 mo of age. In Exp. 1, 100 crossbred heifers received either 1.25 kg of SB/d or 2.5 kg of WCGF/d from approximately 7 to 10 mo of age (91 d; 4 pens/diet), and then were fed 1.25 kg of SB/d for an additional 114 d (4 pens/diet). In Exp. 2, 1.25 kg of SB/d or 1.25 kg of DDG/d was fed to 100 crossbred heifers for 226 d, beginning at 6 mo of age (4 pens/diet). At approximately 13 mo of age, heifers were fed melengestrol acetate (0.5 mg/d) for 14 d, followed by an i.m. injection of PGF(2 alpha) (25 mg) 19 d later to synchronize estrus. Heifers (14 mo of age) received AI for 5 d after PGF(2 alpha), at which time the dietary treatments were ended. Heifers were commingled while grazing on native pasture and were exposed to bulls for approximately 60 d beginning 10 d after the last day of AI. Pregnancy to AI was determined by ultrasound 45 d after the last day of AI. Heifers fed SB in the preliminary experiment had a lower (P < 0.05) synchronization rate (81 vs. 96%) and longer interval (P = 0.05) from PGF(2 alpha) to estrus (76.6 vs. 69.2 h) compared with heifers fed WCGF. In Exp. 1, the age at which the heifers were begun on SB diets did not alter (P > 0.10) the synchronization rate (79%) or timing of estrus after PGF(2 alpha) (77.8 h). In Exp. 2, the synchronization rate (86%) and timing of estrus after PGF(2 alpha) (69.3 h) did not differ (P > 0.10) because of diet. No differences (P > 0.10) were due to diet for AI conception rates (overall mean for each experiment: 76.5, 60, and 68.5%), percentage of all heifers becoming pregnant to AI (67, 46, and 59%), or final pregnancy rates (92, 90, and 90%) in the preliminary experiment, Exp. 1, or Exp. 2, respectively. In summary, SB, DDG, and WCGF can be used as sources of protein in heifer development diets at the inclusion rates used in these studies.  相似文献   
7.
Timely onset of postpartum ovarian activity is vital for optimal reproductive performance of dairy cows. Much depends upon genetic constitution of an animal although several factors interplay to govern the onset of postpartum ovarian activity. South Asian zebu cattle have much longer service period when compared with other exotic or crossbred cattle reared in the same Asian environment, which suggests differences in their genetic makeup. However, the cows with same genetic configuration expressed better reproductive potential when reared under different environment, such as in Brazil and Mexico, which suggests the role of extrinsic factors such as management, nutrition, environment and disease conditions. Better management of animals (provision of proper shade, water and housing, efficient oestrous detection and timely insemination), good quality nutrition supplemented with appropriate minerals and vitamins, prevention of diseases (vaccination, deworming, suitable therapeutic interventions) and application of biotechnology have helped in improving postpartum ovarian activity and, therefore, reproductive performance of zebu cattle in Asia. No comprehensive study appears to have been carried out on the various aspects of reproduction in zebu cattle reared under South Asian socio-agro-climatic conditions. This paper is a modest effort to collect what ever information available and to critically review the postpartum ovarian activity in zebu cattle with special reference to the effect of the various managemental practices and pharmacological interventions.  相似文献   
8.
This study evaluated the effects of AQUI‐S®20E (10% eugenol) sedation on the survival and behaviour of yellow perch Perca flavescens (Mitchill) and Nile tilapia Oreochromis niloticus L. held in high loading densities. Fish were held in 0–300 mg L?1 AQUI‐S®20E (0–30 mg L?1 eugenol) for up to 10 h in static tanks. At 17°C, yellow perch held in 200 and 300 mg L?1 AQUI‐S®20E were lightly sedated for up to 7 h. Yellow perch at 200 and 300 mg L?1 AQUI‐S®20E also had >95% mean survival 7‐days post exposure using loading densities up to 360 g L?1. Nile tilapia were only sedated for ≤3 h in concentrations up to 300 mg L?1 at 22°C and had >90% mean survival at loading densities ≤480 g L?1. Ammonia in tanks increased significantly as loading density increased, but treatment with AQUI–S®20E did not reduce ammonia accumulation. Results suggest that AQUI–S®20E was effective to sedate yellow perch and Nile tilapia at high loading densities, but sedation varied with loading density and species.  相似文献   
9.
10.
Outcomes of Heimlich valve drainage in dogs   总被引:1,自引:1,他引:0  
Objective and design   Retrospective study of the outcomes of Heimlich valve drainage in dogs.
Procedure   Medical records of the past 3 years were retrospectively reviewed. Heimlich valve drainage was used in 34 dogs (median body weight 30 ± 5 kg): lobectomy (n = 15), pneumonectomy (n = 9), intrathoracic oesophageal surgery (n = 2), diaphragmatic hernia repair (n = 1), traumatic open pneumothorax (n = 2), bilobectomy (n = 2), ligation of the thoracic duct (n = 1), and chylothorax and pneumothorax (n = 1 each). Evacuation of air and/or fluid from the pleural cavity was performed with the Heimlich valve following thoracostomy tube insertion. During drainage, the dogs were closely monitored for possible respiratory failure. Termination of Heimlich valve drainage was controlled with underwater seal drainage and assessed with thoracic radiography.
Results   Negative intrathoracic pressure was provided in 29 dogs without any complications. Post pneumonectomy respiratory syncope and post lobectomy massive hemothorax, which did not originate from the Heimlich valve, were the only postoperative complications. Dysfunction of the valve diaphragm, open pneumothorax and intrathoracic localisation of an acute gastric dilatation–volvulus syndrome caused by a left-sided diaphragmatic hernia following pneumonectomy were the Heimlich valve drainage complications.
Conclusions   The Heimlich valve can be used as a continuous drainage device in dogs, but the complications reported here should be considered by veterinary practitioners.  相似文献   
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