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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.
Concept maps have become a ubiquitous tool in education in the last 20 years and are used extensively to teach scientific concepts. A concept map is a tool learners can use to organize information about a topic in terms of key concepts and the relationships among them. As a graphical representation, the map provides an overall picture of a particular concept or topic. This article describes how we have used concept maps to teach physiology to veterinary medical and veterinary technician students enrolled in our on-campus and distance-learning programs.  相似文献   
4.
Veterinary Research Communications - This study evaluated the diuretic, antioxidant, anti-inflammatory, and immunological effects of a commercial diuretic (CD) (composed of ammonium chloride,...  相似文献   
5.
Veterinary Research Communications - Florfenicol (FFC) is a synthetic broad-spectrum antibiotic and garlic has a bactericidal action against coliforms. This study was carried out to compare the...  相似文献   
6.
The aim of this study was to assess the effects of feeding Atriplex halimus (AH) silage treated with two developed enzyme cocktails to sheep on feed intake, nutrient digestibility and ruminal fermentation. The AH silage was treated without or with 2 L of ZAD1® or ZAD2®/1000 kg with 5% molasses and ensiled for 30 days. Barley grain (300 g/head/day) was fed as an energy supplement once daily at 10.00 hours and AH silage with or without enzyme treatment was offered ad libitum to animals twice daily at 09.00 and 16.00 hours. Sheep were fed on four experimental forage diets comprised of AH silage and barley (D1), AH silage treated with ZAD1® and barley (D2), AH silage treated with ZAD2® and barley (D3) and AH silage treated with a combination of ZAD1® and ZAD2® (1:1) and barley (D4). Ensiling AH with enzymes reduced its contents of neutral detergent fiber and acid detergent fiber. The dry matter intake of AH of D2, D3 and D4 decreased (P < 0.001) as compared to D1. However, enzyme‐treated diets had greater total digestible nutrients intake (P < 0.001) as compared to D1. The nutrients digestibility for D2, D3 and D4 were higher than those for D1 (P < 0.001), and were higher for D3 as compared to both D2 and D4. Sheep fed on D3 had highest (P < 0.001) ruminal total volatile fatty acids concentration, ammonia nitrogen concentration and microbial protein yield. It could be concluded that AH silage treated with ZAD1® or ZAD2® improved digestibility and rumen fermentation in sheep.  相似文献   
7.
The objective of the present study was to quantify the marketing margins of cold sheep carcass and barbacoa meat in the southern state of Mexico. Data were obtained from the production chain links (production, industrialization, and marketing) where the marketing margins were calculated along with the benefit/cost (B/C) ratio. In the absolute marketing margin of the final consumer price per kilogram of carcass meat, the producer obtained US$2.7/kg (47 %) of the utilities, while the intermediaries obtained US$3.1/kg (53 %). Considering the final cooked product in barbacoa (typical dish), the margin was US$6.3/kg (29 %) for the producer and US$15.2/kg (71 %) for the intermediaries. The B/C ratio was 1.0, 1.1, 2, and 1.3 for the producer, stocker, butcher, and barbacoa seller, respectively. It is concluded that the best marketing channel for the producer was the producer-stocker-processor (butcher and barbacoa seller). The highest marketing margin was for the intermediaries followed by the producer. The order of importance of the B/C kilogram ratio of meat was for the butcher first, then barbacoa seller, and lastly stocker and producer.  相似文献   
8.
An experiment was completed to determine the effect of Salix babylonica (SB) extract supplementation to the diet of growing lambs. Eighteen Katahdin × Pelibuey male lambs (14?±?2 kg live body weight) were divided randomly in individual cages into three groups and fed three diets varying in SB: a control group was fed on total mixed ration (TMR) without SB (SB0), an SB25 group was fed on TMR plus SB extract at 25 mL/lamb/day, and an SB50 group was fed on TMR plus SB extract at 50 mL/lamb/day on dry matter intake (DMI), average daily gain (ADG), feed efficiency, and in vitro gas production (GP) in lambs fed on TMR. In vitro GP of the TMR fed to lambs was recorded at 2, 4, 6, 8, 10, 12, 24, 48, and 72 h of incubation with 0, 0.6, 1.2, and 1.8 mL extract per gram of DM. Addition of SB extract at low and high doses improved the DMI of lambs by 59.9 and 33.2 %, respectively. Relative to the control, low and high extract doses achieved greater lamb ADG during the experimental period. The asymptotic GP increased (P?<?0.05) with increasing dose of SB extract without affecting the rate of GP or the initial delay before GP begins. Linear increases for in vitro GP with advancing time with different SB extract doses were observed. It is suggested that the use of S. babylonica extract with the rate of 25 mL/lamb/day is beneficial to young lamb’s performance growth and thus can be safely used as a feed additive in diets without any negative effects on animal health.  相似文献   
9.
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   
10.
This study was conducted to investigate the effects of increasing levels of extracts of Byrsonima crassifolia, Celtis pallida, Enterolobium cyclocarpum, Fraxinus excelsior, Ficus trigonata, Phoradendrom brevifolium and Prunus domestica on in vitro gas production (GP) and ruminal fermentation of a high concentrate diet. Plant extracts were prepared at 1 g dry matter (DM)/8 mL of solvent mixture (methanol : ethanol : water, 1:1:8) and added at levels of 0, 0.6, 1.2 and 1.8 mL/g DM of a high concentrate diet. In vitro GP was recorded at 2, 4, 6, 8, 10, 12, 24, 48 and 72 h of incubation. Increasing addition of extracts linearly increased (P < 0.001), the GP24, GP48 and GP72 (mL/g DM), and linearly decreased (P < 0.001), the discrete GP lag time. Moreover, increasing extract doses linearly increased (P < 0.001) the asymptotic GP and decreased (P < 0.001) the rate of GP. GP6 was not impacted by treatments and GP12 increased linearly (P = 0.01) with increasing addition of extracts. Rumen pH declined linearly (P < 0.05) with increasing doses of extracts added. As no interactions (P > 0.05) occurred between the extracts and doses, it could be conclude that all extracts positively modified rumen fermentation at doses of 1.2 to 1.8 mL extract/g diet DM.  相似文献   
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