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81.
Artur Kowalczyk Ewa Łukaszewicz Tomasz Strzała Agnieszka Partyka Joanna Rosenberger 《Reproduction in domestic animals》2020,55(8):984-991
In order to increase the reproductive indices of capercaillie kept in closed breeding facilities, it is necessary to constantly expand the methods of better understanding the characteristics of sperm and their fertilizing potency. The aim of the study was to analyse selected features of capercaillie sperm using flow cytometry and their connection with fertility results. The study included five males, three of which were kept in a family group with eight females and two were kept alone. For sperm viability, acrosome integrity, mitochondrial potential and DNA defragmentation were assessed. Paternity analyses were performed in order to confirm the paternity of the individual and to link the evaluated semen traits with reproductive success. Analyses carried out in the flow cytometer showed any significant differences between males in sperm characteristics. In the semen of male No. 101, the father of all chicks from the analysed family group, 91.3% of live sperm, 91.5% with intact acrosome, 83.6% with active mitochondria and 2.0% with DNA defragmentation were observed. The average fertility rate was 71.0%, and chick hatchability was 100%. Using flow cytometry in the analysis of capercaillie semen and its connection with the results of natural mating, we were able to obtain deeper knowledge about new sperm characteristics that were not examined before and which in the future may be helpful in selecting males for the reproductive flocks and developing assisted reproduction techniques. 相似文献
82.
Summary Unrelated, unselected 2x haploid-species hybrids that produce 2n eggs, by second division restitution and 2n pollen due to
first division restitution were intercrossed to generate 4x progeny. The 19, 4x families were compared with seven cultivars
for tuber yield, tuber appearance and tuber set. The mean yield of the 4x families was 30% higher than the mean yield of the
cultivars. The best five 4x families outyielded the best five cultivars by 57% and 69% at two locations. Cultivars were superior
for tuber appearance and tuber set. The high yields of the 4x families are due to genetic diversity of the 2x parents and
their ability to transmit that diversity to the 4x progeny utilizing 2n gametes. The potential of the 2x×2x breeding method
is dependent on developing 2x hybrid clones that form 2n eggs and possess desirable tuber types; clones producing 2n pollen
and good tuber quality are available. 相似文献
83.
84.
Using affinity chromatography, SDS-PAGE, peroxidase activity assay and mass spectrometry data, a new extracellular peroxidase (CMP) from Chelidonium majus milky sap was isolated and characterized. The protein has a molecular weight of about 40 kDa and belongs to secretory class III plant peroxidases. The peroxidase activity is also accompanied by DN-ase activities. A novel CMP combined with other proteins is probably involved in development and differentiation of the plant and defence against different pathogens. It suggests that the biological activity of C. majus whole plants and extracts may depend not only on its alkaloidal content but also on the presence of biologically active proteins. 相似文献
85.
Penetrating keratoscleroplasty and bimodal grafting for treatment of limbal melanocytoma in a dog 总被引:1,自引:1,他引:0
A 6-year-old, male neutered, German Shepherd dog presented for evaluation of a dark limbal mass OS. Based on the signalment and clinical findings, a presumptive diagnosis of limbal melanocytoma was made. Additionally, OU demonstrated corneal changes consistent with chronic superficial keratitis. Full thickness en bloc resection of the limbal mass was followed with reconstruction and grafting using both frozen cornea and bulbar conjunctiva. Nitrous oxide cryotherapy was utilized as an adjunctive modality for residual neoplastic cell destruction. Histopathologic evaluation confirmed the presumptive diagnosis. At 18 months postoperatively, there was no evidence of recurrence of the limbal melanocytoma. The dog was treated long-term with both topical steroid and tacrolimus 0.03% for control of the chronic superficial keratitis. 相似文献
86.
87.
White JD Norris JM Bosward KL Fleay R Lauer C Malik R 《Journal of Feline Medicine and Surgery》2008,10(3):219-229
Eight cases of glomerular disease in young, related Abyssinian cats are described. Haematuria was the most consistent feature. Six cats developed the nephrotic syndrome. The short-term prognosis was good for cats with haematuria and fair for cats with the nephrotic syndrome as oedema resolved in three of the six cats. Light microscopic examination of renal biopsies from three cats was considered normal or revealed only mild abnormalities. In the three cases subjected to necropsy, histological abnormalities included mild mesangial hypercellularity and adhesions between the glomerular tuft and Bowman's capsule consistent with a focal proliferative glomerulopathy. Further investigation into this glomerulopathy will require ultrastructural and immunohistochemical studies to characterise the glomerular abnormality and genetic analyses to investigate its potential to be an inherited disease. Glomerular disease, potentially a familial one, should be considered in the investigation of persistent haematuria or proteinuria in Abyssinian and related cats. 相似文献
88.
89.
Jeferson Ferreira da Fonseca Fabiana Nunes Zambrini Jos Domingos Guimares Marcio Roberto Silva Maria Emilia Franco Oliveira Felipe Zandonadi Brando Pawel Mieczyslaw Bartlewski Joanna Maria Gonalves Souza‐Fabjan 《Reproduction in domestic animals》2019,54(1):118-125
This study examined the feasibility of transcervical embryo recovery after the hormonal treatment to induce cervical dilation, following the 7‐day oestrous synchronization protocol in multiparous Santa Inês ewes. A total of 23 cyclic ewes received two doses of 37.5 μg of d‐cloprostenol by latero‐vulvar route 7 days apart. After the second injection of d‐cloprostenol, the ewes were checked for oestrus (every 12 hr) and then mated by fertile rams throughout the oestrous period. All ewes received 37.5 μg of d‐cloprostenol (latero‐vulvar) and 1 mg of oestradiol benzoate by either intramuscular (EBim group; n = 12) or intravaginal (EBivg group; n = 11) route 16 hr before embryo flushing. Twenty minutes before the flushing, 50 IU of oxytocin were administered intravenously. The oestrous response (i.e., the percentage of ewes that showed signs of oestrous behaviour after the second d‐cloprostenol injection) was 91.3% (21/23). The proportion of successfully penetrated ewes (81.8% compared with 80.0%), the mean duration of embryo flushing (24.7 ± 2.0 min compared 26.2 ± 1.9 min), the flushing fluid recovery rate (94.8 ± 1.3% compared with 91.0 ± 2.9%) and the average number of structures recovered per ewe (0.5 ± 0.4 compared with 0.8 ± 0.4) did not vary (p > 0.05) between the EBim and EBivg groups. Viable embryos were recovered from 41.2% (7/17) of successfully penetrated ewes. It can be concluded that nonsurgical (i.e., transcervical) embryo collection can be performed in oestrous‐synchronized Santa Inês ewes pretreated with d‐cloprostenol, oxytocin and oestradiol benzoate, with the latter hormone administered by either the intramuscular or intravaginal route. 相似文献
90.
Juliana Dantas Rodrigues Santos Eduardo Kenji Nunes Arashiro Mrio Felipe Alvarez Balaro Joanna Maria Gonalves Souza‐Fabjan Pedro Henrique Nicolau Pinto Clara Vieira de Souza Ceci Ribeiro Leite Jeferson Ferreira da Fonseca Felipe Zandonadi Brando 《Reproduction in domestic animals》2019,54(1):126-128
This study evaluated the cervical transposition method as a tool to select ewes for embryo collection by transcervical route. Adult Santa Inês ewes (n = 50) received Day 0 protocol for superovulation treatments. The cervix transposition test was performed both at oestrus and at the embryo collection time. The latter was preceded by hormonal cervical dilation. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 85.7%, 66.6%, 85.7%, 66.6% and 80.0%, respectively. The kappa index yielded a moderate score (κ = 0.52). In conclusion, the high sensitivity and accuracy indicate that the cervical transposition test is a screening option to select ewes for embryo collection by transcervical route. 相似文献