Flow Cytometry Identification of X- and Y-Chromosome-Bearing Goat Spermatozoa   总被引：3，自引：0，他引：3  

I Parrilla  JM Vazquez  J Roca  EA Martinez 《Reproduction in domestic animals》2004,39(1):58-60

Flow cytometric sorting technology was used to measure the difference in DNA content between X- and Y-chromosome-bearing spermatozoa in bucks. Spermatozoa were analysed by flow cytometry to characterize X- and Y-chromosome-bearing sperm populations and to quantify the DNA difference between them. Two symmetrical, overlapping and clearly separated peaks, corresponding to X- and Y-bearing spermatozoa, were detected. The difference in fluorescence intensity between the peaks was 4.4 +/- 0.03% without any significant inter- or intra-animal variations. Therefore, the identification and selection of high-purity samples of sperm populations for sex sorting is easier in bucks compared with other domestic species.  相似文献   

Key Factors Affecting Reproductive Success of Thoroughbred Mares and Stallions on a Commercial Stud Farm          下载免费PDF全文

EA Lane  MLJ Bijnen  M Osborne  SJ More  ISF Henderson  P Duffy  MA Crowe 《Reproduction in domestic animals》2016,51(2):181-187

To evaluate factors contributing to fertility of thoroughbred mares, data from 3743 oestrous periods of 2385 mares were collected on a large thoroughbred farm in Ireland. Fourteen stallions (mean age 8.3 years; range 4–15 years) had bred 2385 mares (mean age 9.4 years; range 3–24 years). Maiden mares accounted for 12%, mares with a foal at foot for 64%, and barren, slipped or rested mares for 24% of the total. The mean pregnancy rate per cycle was 67.8% (68.6% in year 1 and 66.9% in year 2). Backward stepwise multivariable logistic regression analysis was utilized to develop two models to evaluate mare factors, including mare age, reproductive status, month of foaling, dystocia, month of cover, foal heat, cycle number, treatments, walk‐in status and stallion factors including stallion identity, stallion age, shuttle status, time elapsed between covers and high stallion usage on the per cycle pregnancy rate and pregnancy loss. Old age (p < 0.001) and cover within 20 days post‐partum (p < 0.003) were associated with lowered pregnancy rates. High mare age (p < 0.05) and barren, slipped or rested reproductive status (p = 0.05) increased the likelihood of pregnancy loss. Uterine inflammation or infection, if appropriately treated, did not affect fertility. Only high usage of stallions (used more than 21 times in previous week) was associated with lowered (p = 0.009) pregnancy rates. However, shuttle stallions were more likely to have increased (p = 0.035) pregnancy survival, perhaps reflecting a bias in stallion selection. In conclusion, mare age exerted the greatest influence on fertility; nonetheless, thoroughbreds can be effectively managed to achieve high reproductive performance in a commercial setting.  相似文献   

Surgical and nonsurgical management of and selected risk factors for spontaneous pneumothorax in dogs: 64 cases (1986-1999)     

Puerto DA  Brockman DJ  Lindquist C  Drobatz K 《Journal of the American Veterinary Medical Association》2002,220(11):1670-1674

OBJECTIVE: To compare results of surgical versus nonsurgical treatment of spontaneous pneumothorax in dogs. DESIGN: Retrospective study. ANIMALS: 64 dogs with pneumothorax without any history of antecedent trauma. PROCEDURE: Information on signalment, thoracic radiographic findings, treatment, histologic findings, and outcome was obtained from the medical records. Signalment of affected dogs was compared with signalment of a control population of 260 dogs examined by the emergency service for reasons other than pneumothorax during the study period. RESULTS: Siberian Huskies were overrepresented in the case population, compared with the control population of dogs examined by the emergency service for other reasons. Twenty-eight dogs were treated without surgery (ie, thoracocentesis or tube thoracostomy with or without cage rest), and 36 were treated with surgery. Information regarding final outcome was available for 33 dogs treated with surgery (median follow-up time, 485 days) and 15 dogs treated without surgery (median follow-up time, 366 days). Dogs that underwent surgery had significantly lower recurrence (1/30) and mortality (4/33) rates, compared with dogs treated without surgery (6/12 and 8/15, respectively). A definitive diagnosis was obtained for 38 dogs, including 34 of 36 dogs undergoing surgery; 26 had bullous emphysema and 4 had neoplasia. Two dogs developed spontaneous pneumothorax secondary to migration of plant foreign bodies. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that recurrence and mortality rates for dogs with spontaneous pneumothorax managed surgically were significantly lower than rates for dogs managed by nonsurgical means alone. Early surgical intervention is recommended for definitive diagnosis and treatment of dogs with spontaneous pneumothorax.  相似文献   

Effects of delmadinone acetate on pituitary-adrenal function, glucose tolerance and growth hormone in male dogs     

EA COURT  ADJ WATSON  DB CHURCH  DR EMSLIE 《Australian veterinary journal》1998,76(8):555-560

Objective To characterise the effects of delmadinone acetate on the pituitary-adrenal axis, glucose tolerance and growth hormone concentration in normal male dogs and dogs with benign prostatic hyperplasia.
Design A prospective study involving nine normal male dogs and seven with prostatic hyperplasia.
Procedure Delmadinone acetate was administered to six normal male dogs and seven dogs with benign prostatic hyperplasia at recommended dose rates (1.5 mg/kg subcuta-neously at 0, 1 and 4 weeks). Three normal controls received saline at the same intervals. Blood concentrations of ACTH, cortisol, glucose, insulin and growth hormone were measured over 50 days. Intravenous glucose tolerance and ACTH response tests were performed before and after treatment in the nine normal animals.
Results A substantial suppression of basal and 2 h post-ACTH plasma cortisol secretion was demonstrated after one dose in all dogs given delmadinone acetate. Individual responses after the second and third administration varied between recovery in adrenal responsiveness to continued suppression. Plasma ACTH concentration was also diminished after one treatment. No effects were evident on glucose tolerance or serum growth hormone concentrations.
Conclusion Delmadinone acetate causes adrenal suppression from inhibition of release of ACTH from the pituitary gland. Treated dogs may be at risk of developing signs of glucocorticoid insufficiency if subjected to stressful events during or after therapy. Neither glucose intolerance nor hyper-somatotropism seems likely in male dogs given delmadinone acetate at the recommended dose rate, but the potential for excessive growth hormone secretion in treated bitches remains undetermined.  相似文献   

Lipid Droplet Analysis Using In Vitro Bovine Oocytes and Embryos     

EA Ordoñez‐Leon  H Merchant  A Medrano  M Kjelland  S Romo 《Reproduction in domestic animals》2014,49(2):306-314

The aim of this study was to quantify the content of lipid droplets in bovine oocytes and embryos from Bos indicus (Bi), Bos taurus (Bt) and Bos indicus × Bos taurus (Bi × Bt). Oocytes were aspirated post‐mortem and subjected to in vitro maturation, in vitro fertilization and in vitro development; the medium employed at each stage (TCM‐199, TALP, SOF) was supplemented with (i) serum replacement (SR), (ii) foetal calf serum (FCS) or (iii) oestrous cow serum (ECS). The structure and distribution of the lipid droplets were established using electron microscopy, but were quantified using an optical microscope on semi‐fine toluidine blue‐stained sections. The highest percentage of embryos corresponded to those produced with FCS and ECS, which differed from embryos generated with SR (p < 0.05). The highest percentage of morulae and the lowest percentage of blastocysts were obtained with the SR supplement (p < 0.05). The oocytes cultured in FCS demonstrated a higher number of lipid droplets compared to those cultured in SR and ECS (p < 0.05). Less accumulation of lipids was observed in embryos supplemented with SR. The lowest and highest numbers of lipid droplets in oocytes corresponded to the Bi and Bt strain, respectively. The lowest amount of lipid droplets in embryos was observed in Bi (p < 0.05). In conclusion, supplementation of the in vitro development culture medium (synthetic oviduct fluid) with a synthetic substitute serum produced similar results in terms of embryo development compared to those obtained with FCS, but a decreased degree of lipid droplet accumulation was observed in the in vitro‐cultured embryos.  相似文献   

Retrospective study of 60 cases of feline lymphosarcoma     

EA COURT  ADJ WATSON  AE PEASTON 《Australian veterinary journal》1997,75(6):424-427

Objective To characterise epidemiological and clinical findings, and diagnostic procedures undertaken, in cats with lymphosarcoma at a veterinary teaching hospital.
Design Retrospective case study.
Procedure Hospital records were reviewed for 7159 cats, sick or healthy, examined during a 10-year period (1984 to 1994). Sixty cats with lymphosarcoma were identified and classified by anatomical location of the tumour. Data on breed, age, sex, clinical signs and diagnostic procedures were collated.
Results The prevalence of feline lymphosarcoma in the hospital population was 0.84%. Siamese cats appeared predisposed to lymphosarcoma but other purebreds were not. Males were somewhat overrepresented amongst affected cats. Similar numbers of cases (12 to 18) were seen in each of the four anatomic categories (multicentric, mediastinal, alimentary and extranodal). Cats with mediastinal lymphosarcoma were mostly young and Siamese. Clinical signs in affected cats were varied, usually multiple and often nonspecific. Two of 22 cases tested positive for feline leukaemia virus antigen in blood and 6 of 13 were positive for feline immunodeficiency virus antibody.
Conclusions Extranodal lymphosarcoma seemed more prevalent in this study than reported elsewhere. Siamese cats in the study population may have had a genetic predisposition to lymphosarcoma. Limited evidence suggested feline leukaemia virus may be less important, and feline immunodeficiency virus more important, in the local population than indicated in overseas reports. Additional studies are needed to investigate breed predisposition and feline leukaemia virus and feline immunodeficiency virus status in Australian cats with lymphosarcoma.  相似文献   

The Physcomitrella genome reveals evolutionary insights into the conquest of land by plants     

Rensing SA  Lang D  Zimmer AD  Terry A  Salamov A  Shapiro H  Nishiyama T  Perroud PF  Lindquist EA  Kamisugi Y  Tanahashi T  Sakakibara K  Fujita T  Oishi K  Shin-I T  Kuroki Y  Toyoda A  Suzuki Y  Hashimoto S  Yamaguchi K  Sugano S  Kohara Y  Fujiyama A  Anterola A  Aoki S  Ashton N  Barbazuk WB  Barker E  Bennetzen JL  Blankenship R  Cho SH  Dutcher SK  Estelle M  Fawcett JA  Gundlach H  Hanada K  Heyl A  Hicks KA  Hughes J  Lohr M  Mayer K  Melkozernov A  Murata T  Nelson DR  Pils B  Prigge M  Reiss B  Renner T  Rombauts S  Rushton PJ 《Science (New York, N.Y.)》2008,319(5859):64-69

We report the draft genome sequence of the model moss Physcomitrella patens and compare its features with those of flowering plants, from which it is separated by more than 400 million years, and unicellular aquatic algae. This comparison reveals genomic changes concomitant with the evolutionary movement to land, including a general increase in gene family complexity; loss of genes associated with aquatic environments (e.g., flagellar arms); acquisition of genes for tolerating terrestrial stresses (e.g., variation in temperature and water availability); and the development of the auxin and abscisic acid signaling pathways for coordinating multicellular growth and dehydration response. The Physcomitrella genome provides a resource for phylogenetic inferences about gene function and for experimental analysis of plant processes through this plant's unique facility for reverse genetics.  相似文献   

An ancient developmental induction: heat-shock proteins induced in sporulation and oogenesis   总被引：54，自引：0，他引：54  

S Kurtz  J Rossi  L Petko  S Lindquist 《Science (New York, N.Y.)》1986,231(4742):1154-1157

Every eukaryotic and prokaryotic organism tested to date synthesizes a small number of heat-shock proteins in response to heat and other forms of stress. A particular pattern of heat-shock gene expression was observed during ascospore development in Saccharomyces: heat-shock proteins hsp26 and hsp84 were strongly induced nor inducible by heat shock. Instead, two proteins related to hsp70 were induced. A strikingly similar pattern of expression occurs during oogenesis in Drosophila, suggesting that it may be one of the earliest developmental pathways to evolve in eukaryotic cells.  相似文献   

DNA Replication and Recombination     

EA Adelberg 《Science (New York, N.Y.)》1964,146(3648):1193-1195

  相似文献   

Hsp90 potentiates the rapid evolution of new traits: drug resistance in diverse fungi   总被引：1，自引：0，他引：1  

Cowen LE  Lindquist S 《Science (New York, N.Y.)》2005,309(5744):2185-2189

Hsp90 is a molecular chaperone for many signal transducers and may influence evolution by releasing previously silent genetic variation in response to environmental change. In fungi separated by approximately 800 million years of evolution, Hsp90 potentiated the evolution of drug resistance in a different way, by enabling new mutations to have immediate phenotypic consequences. Resistance was abrogated by Hsp90 inhibitors and by febrile temperatures, suggesting new therapeutic strategies and a clinical benefit of fever. During selection in a human host, drug resistance that was initially Hsp90-dependent evolved toward independence. Thus, Hsp90 can act in diverse ways to couple environmental contingency to the emergence and fixation of new traits.  相似文献