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41.
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   
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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   
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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   
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This study compared endometrial cytology vis‐a‐vis uterine fluid cytology for assessment of uterine health in clinically normal and subclinical endometritis (SE)‐affected buffaloes. Uterine fluid samples and endometrial samples were collected from the buffaloes (n = 38) at oestrus using blue sheath and cytobrush, respectively. The smears were stained with Field stain for 3 minutes, and a minimum of 400 cells were counted in each smear for determination of the percentage of polymorphonuclear (PMN) leucocyte. The incidence of subclinical endometritis, based on the cytobrush cytology, was 23.08%. The correlation between cytobrush cytology with uterine fluid cytology was positive and significant (r = .37; p = .02). The ratio of PMN leucocyte in cytobrush cytology to uterine fluid cytology was 1:2.4. ROC analysis revealed that the threshold value of 6.16% PMN leucocyte in uterine fluid cytology showed a diagnostic sensitivity and specificity of 100% in differentiating normal from SE‐affected buffaloes. In conclusion, collection of uterine fluid was easier compared to collection of endometrial samples using cytobrush and the percentage of PMN leucocyte in uterine fluid cytology can be used as a tool for diagnosis of subclinical endometritis in buffaloes.  相似文献   
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Objective To provide a detailed discussion of the aetiology and pathophysiology of hiatal hernia in both humans and small animals, and review current medical and surgical treatments.
Design Review article.
Summary Hiatal hernia is not completely understood in humans or animals. It has a complex multifactorial aetiology and pathophysiology. A primary disturbance of the lower oesophageal sphincter has not been shown in humans or animals. Knowledge of pathophysiology is necessary to institute appropriate treatment.
Medical and/or surgical therapy is not indicated in asymptomatic cases. Medical treatment should be used for up to 1 month in stable cases of sliding hiatal hernia. Paraoesophageal hiatal hernias and any large sliding hiatal hernia should be considered for prompt surgical treatment. Surgical techniques used depend on the type of hiatal hernia present.
Surgical treatment of hiatal hernia cases should be performed by experienced surgeons, and must include hiatal closure and gastropexy. The Nissen fundoplication procedure has been discontinued in the veterinary field due to poor success rates, coupled with the published view that there is a marked difference in pathophysiology between humans and dogs. Reported complications associated with the original Nissen fundoplication technique are identical in the human and veterinary literature. There have been no complications reported with use of the modified or 'floppy' Nissen fundoplica-tion in dogs. Both oesophagopexy and Nissen fundoplication require further evaluation in small animals.  相似文献   
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The objectives of this study were to determine (i) whether an association exists between individual pharmacokinetic parameters and treatment outcome when feeder cattle were diagnosed with bovine respiratory disease (BRD) and treated with gamithromycin (Zactran®) at the label dose and (ii) whether there was a stronger association between treatment outcome and gamithromycin concentration in plasma or in the pulmonary epithelial lining fluid (PELF) effect compartment. The study design was a prospective, blinded, randomized clinical trial utilizing three groups of 60 (362–592 lb) steers/bulls randomly allocated within origin to sham injection or gamithromycin mass medication. Cattle were evaluated daily for signs of BRD by a veterinarian blinded to treatment. Animals meeting the BRD case definition were enrolled and allocated to a sample collection scheme consisting of samples for bacterial isolation (bronchoalveolar lavage fluid and nasopharyngeal swabs) and gamithromycin concentration determination (PELF and plasma). Gamithromycin susceptibility of M. haemolytica (n = 287) and P. multocida (n = 257) were determined using broth microdilution with frozen panels containing gamithromycin at concentrations from 0.03 to 16 μg/mL. A two‐compartment plasma pharmacokinetic model with an additional compartment for gamithromycin in PELF was developed using rich data sets from published and unpublished studies. The sparse data from our study were then fit to this model using nonlinear mixed effects modeling to estimate individual parameter values. The resulting parameter estimates were used to simulate full time–concentration profiles for each animal in this study. These profiles were analyzed using noncompartmental methods so that PK/PD indices (AUC24/MIC, AUC/MIC, CMAX/MIC) could be calculated for plasma and PELF (also T>MIC) for each individual. The calculated PK/PD indices were indicative that for both M. haemolytica and P. multocida a higher drug exposure in terms of concentration, and duration of exposure relative to the MIC of the target pathogen, was favorable to a successful case outcome. A significant association was found between treatment success and PELF AUC0–24/MIC for P. multocida. The calves in this study demonstrated an increased clearance and volume of distribution in plasma as compared to the healthy calves in two previously published reports. Ultimately, the findings from this study indicate that higher PK/PD indices were predictive of positive treatment outcomes.  相似文献   
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