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31.
This study compared artificial insemination pregnancy rate (AI‐PR) between 14‐day CIDR‐GnRH‐PGF2α‐GnRH and CIDR‐PGF2α‐GnRH synchronization protocol with two fixed AI times (56 or 72 hr after PGF2α). On day 0, heifers (= 1311) from nine locations assigned body condition score (BCS: 1, emaciated; 9, obese), reproductive tract score (RTS: 1, immature, acyclic; 5, mature, cyclic) and temperament score (0, calm; and 1, excited) and fitted with a controlled internal drug release (CIDR, 1.38 g of progesterone) insert for 14 days. Within herd, heifers were randomly assigned either to no‐GnRH group (= 635) or to GnRH group (= 676), and heifers in GnRH group received 100 μg of GnRH (gonadorelin hydrochloride, IM) on day 23. All heifers received 25 mg of PGF2α (dinoprost, IM) on day 30 and oestrous detection aids at the same time. Heifers were observed for oestrus thrice daily until AI. Within GnRH groups, heifers were randomly assigned to either AI‐56 or AI‐72 groups. Heifers in AI‐56 group (= 667) were inseminated at 56 hr (day 32 PM), and heifers in AI‐72 group (= 644) were inseminated at 72 hr (day 33 AM) after PGF2α administration. All heifers were given 100 μg of GnRH concurrently at the time AI. Controlling for BCS (< .05), RTS (< .05), oestrous expression (< .001), temperament (< .001) and GnRH treatment by time of insemination (< .001), the AI‐PR differed between GnRH treatment [GnRH (Yes – 60.9% (412/676) vs. No – 55.1% (350/635); < .05)] and insemination time [AI‐56 – 54.6% (364/667) vs. AI‐72 – 61.8% (398/644); (< .01)] groups. The GnRH treatment by AI time interaction influenced AI‐PR (GnRH56 – 61.0% (208/341); GnRH72 – 60.9% (204/335); No‐GnRH56 – 47.9% (156/326); No‐GnRH72 – 62.8% (194/309); < .001). In conclusion, 14‐day CIDR synchronization protocol for FTAI required inclusion of GnRH on day 23 if inseminations were to be performed at 56 hr after PGF2α in order to achieve greater AI‐PR.  相似文献   
32.
OBJECTIVE: To evaluate adverse effects of long-term oral administration of carprofen, etodolac, flunixin meglumine, ketoprofen, and meloxicam in dogs. ANIMALS: 36 adult dogs. PROCEDURES: Values for CBC, urinalysis, serum biochemical urinalyses, and occult blood in feces were investigated before and 7, 30, 60, and 90 days after daily oral administration (n = 6 dogs/group) of lactose (1 mg/kg, control treatment), etodolac (15 mg/kg), meloxicam (0.1 mg/kg), carprofen (4 mg/kg), and ketoprofen (2 mg/kg for 4 days, followed by 1 mg/kg daily thereafter) or flunixin (1 mg/kg for 3 days, with 4-day intervals). Gastroscopy was performed before and after the end of treatment. RESULTS: For serum gamma-glutamyltransferase activity, values were significantly increased at day 30 in dogs treated with lactose, etodolac, and meloxicam within groups. Bleeding time was significantly increased in dogs treated with carprofen at 30 and 90 days, compared with baseline. At 7 days, bleeding time was significantly longer in dogs treated with meloxicam, ketoprofen, and flunixin, compared with control dogs. Clotting time increased significantly in all groups except those treated with etodolac. At day 90, clotting time was significantly shorter in flunixin-treated dogs, compared with lactose-treated dogs. Gastric lesions were detected in all dogs treated with etodolac, ketoprofen, and flunixin, and 1 of 6 treated with carprofen. CONCLUSIONS AND CLINICAL RELEVANCE: Carprofen induced the lowest frequency of gastrointestinal adverse effects, followed by meloxicam. Monitoring for adverse effects should be considered when nonsteroidal anti-inflammatory drugs are used to treat dogs with chronic pain.  相似文献   
33.
Antioxidants are known to prevent the reactive oxygen species (ROS)‐mediated peroxidative damage to the membrane lipids during hypothermic storage of mammalian spermatozoa. We hypothesized here that ROS also affect the lipid–protein interactions, thereby diminishing the membrane's integrity and proteins' anchorage to the bilayer. Antioxidants prevent these damages by scavenging the ROS. Ejaculates from Patanwadi rams were pooled after subjective evaluation and centrifuged using Percoll®. Sperm pellet was resuspended in soya lecithin–Tris–fructose diluent (400 × 106 cells/ml) containing either antioxidants (100 IU/ml catalase + 10 mM reduced glutathione) or no antioxidant. Aliquots were chilled to 5°C in a cabinet and stored in a refrigerator at 3–5°C for 72 hr. Sperm motility, viability, lipid peroxidation (LPO) and hypo‐osmotic swelling test (HOST) were performed at 0, 24, 48 and 72 hr. Sperm proteins extracted with 0.5% Triton X‐100 were resolved by SDS‐PAGE and quantified using Quantity One software (Bio‐Rad, USA). The rapid motility, linearity and straight‐line velocity (VSL) were found significantly (p < .05) higher in the antioxidant‐treated group compared to the control at 48 hr of storage. Sperm viability was found comparable between the groups. Higher HOST response and lower LPO were found in the antioxidant‐treated sample compared to the control both at 48 and at 72 hr. Overall, the proteins P1 (106.09 kDa), P2 (87.00 kDa) and P4 (51.14 kDa) were lower (p < .05) in the sperm extract of antioxidant‐treated group compared to the control. The content of P4 (51.14 kDa) in sperm extract was found to increase (p < .05) earlier (48 vs. 72 hr) in the control group compared to the antioxidant‐treated group. Altogether, the results suggested that antioxidants reduced LPO in spermatozoa, resulting in higher sperm motility, plasma membrane integrity and protection of proteins' anchorage to the plasma membrane at 48 and 72 hr of storage.  相似文献   
34.
Only a few studies have described hormonal treatments for induction of synchronicity and gamete collection in Nile tilapia (Oreochromis niloticus), both important for assortative matings in breeding programmes and essential for polyploidy technologies. In this study, we compared the effectiveness of carp pituitary extract (CPE), Nile tilapia pituitary extract (TPE), human chorionic gonadotropin (hCG) and gonadotropin‐releasing hormone (GnRH) protocols on the induction of spawning and egg production in Nile tilapia. Among the hormonal treatments analysed, only hCG was effective for producing viable gametes for in vitro fertilization. To verify the viability of this hormonal treatment, hCG was tested using different doses (1000, 2000, 3000, 4000 and 5000 IU/kg) in a large number of females (208 animals) from two Nile tilapia lines. The results indicated that hCG doses between 1000 and 5000 IU/kg could be used to induce final oocyte maturation in Nile tilapia with collection of stripped oocytes. This is the first study to report differential reproductive responses to hormonal treatment between tilapia lines: line 1 was more efficient at producing eggs and post‐hatching larvae after hCG induction than line 2. In conclusion, we demonstrated that the hCG protocol may be applied on a large scale to induce final oocyte maturation in Nile tilapia. The development of a protocol for in vitro fertilization in Nile tilapia may aid in breeding programmes and biotechnological assays for the development of genetically modified lines of Nile tilapia.  相似文献   
35.
Thirty spring wheat varieties were evaluated and classified into eight different groups on the basis of their grain yield performance and phosphorus (P) uptake using Metroglyph analysis. Significant variability was observed for grain and biomass yield, plant height, P content in grain and straw, total P uptake and phosphorus harvest index and P use efficiency traits. Varieties WH 711 and PBW 343 exhibited high grain yield as well as high P uptake (HGY-HP). WH 283 and UP 2425 with high index score of 19 and 16 respectively, constituted the high grain yield-medium P uptake (HGYMP) group. Both these varieties, though had similar grain yield of 5348 kg/ha, but WH 283 (12.64 kg/ha) utilized much lower P as compared to UP 2425 (16.94 kg/ha). Moreover, WH 283 (81.64) also showed higher values for phosphorus harvest index (PHI) than UP 2425 (67.88%). P uptake of WH 283 was comparable with that of Raj 3765 (10.78 kg/ha) and grouped into high grain yield and low P uptake (HGY-LP) group. The grain yield performance of these two varieties with a relatively low P uptake is reflected in their high index score for P use efficiency thus, earmarking them for low P regimes. Variety HW 2006, despite low grain yields of 4665 kg/ha had high index score of 16 due to its higher value for Phosphorus Biological (PBER) and Economic Yield (PEER) Efficiency Ratio as it has effected least (7.18 kg/ha) P mobilization. In addition high P translocation in the grain was also observed for this variety. Inter-mating of genotypes like HW 2006, UP 2338 and HW 2016 with those belonging to HGY-HP (PBW 343 and WH 711) and HGY-LP (Raj 3765 and WH 283) would be an ideal strategy to develop the cultivars for efficient phosphorus use.  相似文献   
36.
Filled Skutterudite Antimonides: A New Class of Thermoelectric Materials   总被引:2,自引:0,他引:2  
A class of thermoelectric materials has been synthesized with a thermoelectric figure of merit ZT (where T is temperature and Z is a function of thermopower, electrical resistivity, and thermal conductivity) near 1 at 800 kelvin. Although these materials have not been optimized, this value is comparable to the best ZT values obtained for any previously studied thermoelectric material. Calculations indicate that the optimized material should have ZT values of 1.4. These ternary semiconductors have the general formula RM4X12 (where R is lanthanum, cerium, praseodymium, neodymium, or europium; M is iron, ruthenium, or osmium; and X is phosphorus, arsenic, or antimony) and represent a new approach to creating improved thermoelectric materials. Several alloys in the composition range CeFe4-xCoxSb12 or LaFe4-xCoxSb12 (0 < x < 4) have large values of ZT.  相似文献   
37.
In this study, alteration in the follicular fluid composition and luteal function was investigated in the buffalo with endometritis. Genitalia were classified into cytological and purulent endometritis on the basis of polymorphonuclear cell cut off while non‐endometritis served as control (n = 10/group). In the follicular phase, the number of surface follicles was counted, diameter of the largest follicle was measured and the follicular fluid was assayed for total protein, cholesterol, malondialdehyde (MDA), total antioxidant capacity (TAC), oestradiol (E2) and progesterone (P4). The P4 content of corpus luteum during mid‐luteal phase was estimated by radioimmunoassay. Ovaries from the follicular phase of oestrous cycle showed no significant difference in the total number of surface follicles, size of the largest follicle and volume of follicular fluid in the buffaloes with and without endometritis (> .05). However, the antral fluid of the largest follicle from the genitalia of buffalo with cytological and purulent endometritis showed a significant decrease in the concentration of total protein, cholesterol, TAC and E2 and a significant increase in the concentration of MDA and P4 (< .05). The results indicated that there is an association between endometritis and decreased ovarian function.  相似文献   
38.
Two experiments were conducted to determine (i) factors influencing calf temperament at weaning, (ii) association between heifer–calf temperament at weaning and temperament at breeding and (iii) effect of heifer–calf temperament on pregnancy rate per artificial insemination (P/AI). In experiment 1, beef cows and their calves (n = 285) from three farms were used. Sire docility estimated progeny difference (EPD) score, birth type (normal or assisted), calf gender, calf behaviour (during 1st 4 weeks) and calf health status (until weaning) were recorded. Cows and calves were assigned a temperament score (0—calm; 1—excitable), and all cows were given a body condition score (BCS, 1–9; 1—emaciated; 9—obese) at weaning. Calf's illness (< .05), low sire docility EPD score (< .05), altered gait (< .05), altered resting behaviour (< .01), reduced/no play behaviour (< .05) and cow excitable temperament (< .001) increased calf excitable temperament at weaning. In experiment 2, replacement heifer–calves (n = 758) from 12 farms were assigned a temperament score at weaning and later at breeding. Blood from 40 calves at weaning and 31 heifers at initiation of synchronization (same animals) was collected by coccygeal venipuncture for determination of circulating cortisol and substance P concentrations. Heifers were assigned a BCS and reproductive tract score (RTS, 1–5; 1—immature, acyclic; 5—mature, cyclic), synchronized for fixed time AI, observed for oestrus and were artificially inseminated. Cortisol concentrations were increased in excitable heifer–calves compared to calm heifer–calves at weaning (< .05), and substance P was increased in excitable compared to calm females both at weaning and breeding (< .05). Low sire EPD docility score (< .01), heifer–calf excitable temperament at weaning increased excitable temperament at breeding (< .01). Controlling for BCS categories (< .01), oestrous expression (< .0001) and temperament at breeding by oestrous expression (< .05), the calf's excitable temperament at weaning (< .001) reduced P/AI (Calm, 62.7 (244/389) vs. Excitable, 53.4% (197/369); < .01). In conclusion, selection of docile cows and sires with greater docility EPD score should be given consideration to reduce calf excitement. Temperament in beef female can be detected earlier in their life and could be used as a tool in the selection process and to improve their performances.  相似文献   
39.
In this study, a dot‐enzyme‐linked immunosorbent assay (Dot‐ELISA) was evaluated in comparison with a complement fixation test (CFT) for the detection of Campylobacter antibodies in sheep sera. Acid glycine extracts (AGE) of both Campylobacter fetus ssp. fetus and Campylobacter jejuni strains that had been isolated from the gall‐bladder of slaughtered sheep was used as antigen in both tests. A total of 153 sheep sera from aborted (74) and slaughtered (79) sheep were examined by both Dot‐ELISA and CFT. Twenty‐two sera showed anti‐complementary activity were not suitable for CFT. Of the 22 sera showing anti‐complementary activity, two sera were found to be positive in Dot‐ELISA. Eighty‐eight (67.2%) of the remaining 131 sera were negative by both Dot‐ELISA and CFT using AGE of both Campylobacter strains whereas 43 sera (32.8%) gave different reaction patterns in Dot‐ELISA and CFT with the extracts of both Campylobacter strains. Twelve sera were positive by both tests using AGE of C. fetus ssp. fetus but CFT failed to detect antibodies in nine of these sera when AGE of C. jejuni was used. Twelve sera were positive by both tests only when AGE of C. fetus ssp. fetus was used. Eleven sera were positive only by CFT. Seven of these reacted only with the AGE of C. fetus ssp. fetus and four sera were positive by using AGE of both Campylobacter strains. The remaining eight sera were found to be positive only by dot‐immunobinding assay either with the AGE of both Campylobacter strains or with the AGE of one of the Campylobacter strains. It is concluded that Dot‐ELISA using AGE from C. fetus ssp. fetus could be employed for the detection of Campylobacter antibodies in sheep sera and the additional use of AGE from C. jejuni as antigen appeared not to be profitable for this purpose.  相似文献   
40.
DBA/2FG-pcy mice developed the chronic renal failure by the progressive polycystic formation at five months old. Their bilaterally enlarged kidneys occupied about 15% of the body weight. It was about 9 times larger than the normal kidney of DBA/2N mice. A large number of various-sized cysts appeared in cortex and medulla of bilateral light-yellow kidneys of sponge-like shape. Blood urea nitrogen and creatinine increased. Red blood cells (746 +/- 39 x 10(4)/mm3), hemoglobin (8.8 +/- 0.4 g/dl) and hematocrits (31.1 +/- 1.5%) were lower than those of normal control mice. Serum erythropoietin level and reticulocytes did not increase. In addition, the treatment with exogenous erythropoietin improved the anemia in DBA/2FG-pcy mice. It was suggested that the anemia in DBA/2FG-pcy mice was due to the disorder of erythropoietin production caused by the progressive polycystic formation in kidneys.  相似文献   
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