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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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Chlamydia gallinacea is a recently described bacterial species in a genus known to infect and cause disease in animals and humans. Our report describes the identification of C. gallinacea infection in free‐range laying chickens (Gallus gallus) in Australia, and the identification of C. gallinacea infection in a parrot, a wild Australian galah (Eolophus roseicapillus). There is currently little knowledge of the effects of C. gallinacea infection on avian hosts, but it has been linked to respiratory disease in humans and could potentially cause similar disease in other species. Our report highlights the need for further study and surveillance of Chlamydia species in both wild and domestic hosts in Australia.  相似文献   
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Effect of sperm concentrations and cumulus cells (CCs) on porcine IVF was re‐evaluated using current improved IVM and IVC system. Our results showed that both CCs and sperm concentration had significant effect on penetration rate, frequency of polyspermy and embryonic development. The best IVF results were obtained with oocytes with CCs fertilized with 0.5 × 105 sperm/ml. Such an IVP system works on both sow and gilt oocytes.  相似文献   
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Normal mammalian sex differentiation takes place in three genetically controlled steps: chromosomal sex determination (XX or XY), gonadal differentiation and development of the phenotypic sex. Animals are considered to be sex reversed if chromosomal sex determination and gonadal development are not in agreement. In this report, sex reversal is described in a 1.5-year-old Podenco dog that was referred because of suspected recurrent growth of a previously removed os clitoridis in the vulva. With that exception the dog was phenotypically female, but had never been in oestrus and exhibited male behaviour. Abdominal ultrasonography showed a small tubular structure dorsal to the bladder, consistent with a uterus. An ovoid structure resembling a gonad was visible between the right kidney and inguinal canal. Plasma testosterone concentrations before and after GnRH administration indicated the presence of functional testicular tissue. Two testes, each with its epididymis and ductus deferens, and a complete bicornuate uterus were removed surgically. Cytogenetic analysis of peripheral blood lymphocytes showed a normal female karyotype (78, XX). These findings are consistent with the diagnosis of an XX male. PCR analysis of genomic DNA revealed that the SRY gene was absent. In summary, this report describes the first SRY-negative XX male Podenco dog with an almost complete female phenotype despite high basal and stimulated plasma testosterone concentrations. It is hypothesized that the clinical observations in this dog may have been caused by reduced and delayed Müllerian-inhibiting substance secretion and the absence of conversion of testosterone to dihydrotestosterone due to 5α-reductase deficiency.  相似文献   
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