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41.
The success of embryo production in vitro depends upon the use of an efficient oocyte retrieval technique, and the best results have been obtained by laparoscopic aspiration. The aim of this study was to evaluate the effect of consecutive sessions of follicular aspiration on the quantity, quality and in vitro maturation competence of oocytes obtained from ewes subjected to hormonal stimulation. Six Santa Ines ewes underwent nine sessions of follicular aspiration by laparoscopy with a 7‐day interval between sessions, totalling 56 aspirations. After 24 h of culture, oocytes were stained and classified according to the stage of nuclear and cytoplasmic maturation. Oocyte retrieval rate was 61.4 ± 2%, resulting in a total of 249 oocytes. No significant variation was observed between sessions (p > 0.05). The average number of oocytes retrieved from each ewe was 6.4 ± 2 per session and 42 ± 4 in total. No significant difference was observed between the frequencies of the different stages of nuclear maturation: 32.72% mature, 40.74% immature and 26.54% degenerated/indeterminate oocytes; however, a significant difference was observed between the frequencies of the different stages of cytoplasmic maturation: 10.7% mature, 73.25% immature and 16.05% degenerated/indeterminate oocytes. No significant difference was observed in nuclear or cytoplasmic maturation between the weeks of procedure. We conclude that after nine consecutive sessions of follicular aspiration, the quantity and quality of retrieved oocytes remained unchanged as well as the levels of nuclear and cytoplasmic maturation obtained, demonstrating the viability of this technique for repetitive follicular aspirations on the same donor.  相似文献   
42.
Mating‐induced endometritis (MIE) is ubiquitous in the horse after natural mating and artificial insemination with frozen/thawed semen causing the most aggressive response. The majority of mares eliminate MIE 24–48 h after insemination. An endometrial explant culture was tested as a potential in vitro exemplar for sperm‐induced MIE. Endometrial prostaglandin F (PGF) secretion and expression of interleukin‐8 (IL‐8) were used as markers of inflammation. Endometrial explants were cultured from uteri collected from follicular phase mares. Explants were challenged with 1 or 10 × 106 sperm/ml frozen/thawed semen, chilled semen, washed sperm or seminal plasma. Medium was collected 24 and 72 h after challenge and assayed for PGF by radioimmunoassay. Treatment of endometrial explants with frozen/thawed, chilled semen or washed sperm did not change the secretion of PGF compared with untreated controls. However, 24 h after challenge cultured explants expressed IL‐8. The in vitro endometrial explant system did not represent the in vivo response to semen when PGF was used as a marker of inflammation, yet the use of gene expression as an inflammatory marker warrants further investigation.  相似文献   
43.
The rate of infection of pods byP. palmivora at the lower trunk of a cacao tree is always higher than of those in the canopy. This is often held as a proof that the soil is the primary source of infection. An experiment has indicated that climatic conditions at the beginning of the rainy season in Western Nigeria do not favour infection of pods in the canopy, which may also explain the said phenomenon.Samenvatting In Nigeria evenals in andere landen is waargenomen dat doorP. palmivora aangetaste cacaokolven in het begin van de regentijd vooral voorkomen aan de stam en dat het aantastingspercentage van de stamvruchten over het gehele seizoen genomen aanzienlijk hoger light dan dat van de vruchten in de kroon. Een proef waarbij ongeveer 10% van de stamvruchten en ook van de vruchten in de kroon werd geïnoculeerd bij het begin van de regentijd, wees uit dat in deze periode van het jaar de klimaatomstandigheden in de kroon waarschijnlijk ongunstig zijn voor infectie.Een hoog percentage aangetaste stamvruchten in genoemde periode mag derhalve niet zonder meer gezien worden als bewijs dat de grond in het begin van de regentijd de enig belangrijke besmettingsbron van de ziekte zou zijn.  相似文献   
44.
Six 3‐year‐old goats (three males and three females) weighing 60.0 ± 18 kg (mean ± SD) were used to investigate the effect of medetomidine (MED; 20 µg kg?1 IV) and its antagonism with atipamezole (ATI; 100 µg kg?1 IV) on physiologic responses (heart rate (HR; beats minute?1), respiratory rate (RR; breaths minute?1), electrocardiogram (ECG), rectal temperature (T; °C), blood pressure (oscillometric; mm Hg), sedation (SED), posture (REC), analgesia (ALG), and stress‐related hormonal and metabolic responses (epinephrine and norepinephrine (high performance liquid chromatography with electrochemical detection), cortisol (COR; µg dL?1; radioimmunoassay), glucose (GLU; mg mL?1; enzymatic colorimetric assay), and free fatty acids (modified enzymatic colorimetric assay)); each goat received ATI or SAL in random order separated by 1 week. Jugular catheters were placed for drug administration and blood sampling (10–12 mL sample?1) using a lidocaine skin block (20 mg) 2 hours prior to beginning of each trial; during this trial, goats breathed room air. Physiologic parameters were measured, SED, REC, and ALG were scored, and blood samples were collected from jugular catheters at baseline (time = ?30 minutes), 5 minutes post‐MED administration (time = ?25 minutes), 25 minute post‐MED administration and immediately prior to antagonism (time = 0 minute), and at 5, 30, 60, and 120 minutes after administering ATI or SAL. ALG was tested by clamping the withers and metacarpus with hoof testers fitted with a force transducer to measure applied isometric force (lb) (a technique used previously in goats to evaluate analgesia). Continuous variables were analyzed by Repeated Measures analysis of variance (anova ); categorical data were analyzed using a Friedman Repeated Measures anova on ranks. A p‐value of <0.05 was considered significant. If a significant difference was found, a Dunnett's pair‐wise comparison of means was conducted. Differences between ATI and SAL were examined at 5, 30, 60, and 120 minutes using a paired t‐test with a Bonferroni correction. Administration of MED resulted in a decrease in T (38.7 ± 0.3 to 34.5 ± 0.4 °C), HR (78 ± 19 to 55 ± 9), and RR (31 ± 12 to 14 ± 5) over time; an increase in mean arterial blood pressure (90 ± 19 to 132 ± 23), COR (0.254 ± 0.125 to 4.327 ± 1.233), and GLU (82.0 ± 13.2 to 255.9 ± 38.9); and changes in SED (alert to marked sedation), REC (standing to recumbent), and ALG (metacarpus = 5 ± 2 to 14 ± 0; withers = 3 ± 2 to 14 ± 0). GLU was 62–70% higher at 60 and 120 minutes and COR was 336% higher after SAL than after ATI at 120 minutes; at 30, 60, and 120 minutes, T was 4–10% higher after ATI than SAL. There were no other significant differences. REC, SED, and ALG were antagonized after ATI. ATI did not antagonize the effect of MED on HR, RR, or MAP, but stabilized T and antagonized the increase in GLU and COR.  相似文献   
45.
ABSTRACT A collection of race 1 and race 2 isolates of Fusarium oxysporum f. sp. lycopersici was screened for vegetative compatibility and characterized by random amplified polymorphic DNA (RAPD) analysis to establish the identity and genetic diversity of the isolates. Comparison of RAPD profiles revealed two main groups that coincide with vegetative compatibility groups (VCGs). In addition, several single-member VCGs were identified that could not be grouped in one of the two main RAPD clusters. This suggests that F. oxysporum f. sp. lycopersici is a polyphyletic taxon. To assign avirulence genotypes to race 1 isolates, they were tested for their virulence on a small set of tomato lines (Lycopersicon esculentum), including line OT364. This line was selected because it shows resistance to race 2 isolates but, unlike most other race 2-resistant lines, susceptibility to race 1 isolates. To exclude the influence of other components than those related to the race-specific resistance response, we tested the virulence of race 1 isolates on a susceptible tomato that has become race 2 resistant by introduction of an I-2 transgene. The results show that both line OT364 and the transgenic line were significantly affected by four race 1 isolates, but not by seven other race 1 isolates nor by any race 2 isolates. This allowed a subdivision of race 1 isolates based on the presence or absence of an avirulence gene corresponding to the I-2 resistance gene. The data presented here support a gene-for-gene relationship for the interaction between F. oxysporum f. sp. lycopersici and its host tomato.  相似文献   
46.
47.
An artificial insemination programme was carried out to study the effect of factors such as depth of semen deposition, inseminator skill, farm, sire and expression of oestrus on pregnancy rate in Murciano-Granadina (MG) goats during non-breeding season and using frozen semen. Frozen-thawed semen from six males was applied by three technicians to inseminate a total of 551 goats in 17 farms distributed throughout the Mediterranean area of Spain. Pregnancy rate was determined at 6 weeks after insemination by transabdominal ecography. Overall pregnancy rate was 57%. Farm and depth of semen deposition affected pregnancy rate, whereas the sire and the technician had no effect. The deeper the semen was deposited in the genital tract, the higher was the rate of pregnancy obtained, being greater when the catheter reached the uterus. In spite of the relevant difference observed (48.2% vs 59.0%), pregnancy rate of females not coming into oestrus until 30 h after sponge removal was not significantly different, compared with those showing oestrus during the OD procedure. In conclusion, our field assay data on AI in MG goat with frozen-thawed semen showed that post-cervical insemination presented significantly greater pregnancy rate in comparison to when semen is deposited in the vagina or in the caudal part of the cervix.  相似文献   
48.
Objective To describe the clinical presentation, ultrasound findings, management and outcome in horses with muscle tear injuries of the hindlimbs. Design Retrospective case series Procedure Medical records of eight horses were reviewed and information on signalment, history, presenting complaint, physical examination findings and further diagnostic tests were recorded. Diagnosis of muscle injury was determined by the presence of abnormal ultrasound findings, compared with the contralateral limb, and, when required, nuclear scintigraphy. Follow-up information was obtained via telephone interviews with owners, trainers and referring veterinarians. Results Muscle tears causing lameness were identified in the middle gluteal (3), semitendinosus (1), semimembranosus (2) and gracilis (2) muscles. Tears were classified by ultrasound imaging as partial (6) or complete (2). The degree of lameness did not appear to be indicative of the extent of injury or of completion of healing. Long-term follow-up was available for seven horses and the outcome was favourable in six cases. Conclusions and clinical relevance Ultrasonography is useful in the diagnosis and assessment of moderate to severe muscle strain injuries. The prognosis appears to be favourable in most cases, although recurrence of injury and lameness can delay the return to athletic activity and an inferior outcome with persistent gait abnormality may occur.  相似文献   
49.
Ultrasound is one of the most promising forms of non‐invasive contraception and has been studied in several animal models. The objective of the current investigation was to determine the most practical and effective application protocol for dog sterilization. A total of 100 dogs were divided into five equal groups. Group A received 5‐min applications three times performed at 48‐hr intervals and covering the entire testicular area at frequency of 1 MHz; Group B received 5‐min applications three times performed at 48‐hr intervals over the dorso‐cranial area of the testis at frequency of 3 MHz; Group C received three sequential 5‐min applications (at 5‐min intervals between applications) covering the entire testicular area at frequency of 1 MHz; Group D received 15‐min applications two times performed at 48‐hr intervals and covering the entire testicular area at frequency of 1 MHz. The experimental groups' ultrasound had an intensity of 1.5W/cm2. The Control Group had the same procedure as Group A, but with the transducer switched‐off. Dogs were surgically castrated 40 days following the treatment for histological examination. Azoospermia, testicular volume reduction and apparently irreversible testicular damage were achieved by Group A. No effects were noticed in the other groups. Testosterone levels remained within physiological range with all application protocols. A regimen of three applications of ultrasound at 1 MHz, and 1.5 W/cm2, lasting 5 min with an interval of 48 h was effective as permanent sterilization in the dog without hormonal impact.  相似文献   
50.
The aim of this study was to evaluate the influence of Hoechst 33342 (H‐42) concentration and of the male donor on the efficiency of sex‐sorting procedure in canine spermatozoa. Semen samples from six dogs (three ejaculates/dog) were diluted to 100 × 106 sperm/ml, split into four aliquots, stained with increasing H‐42 concentrations (5, 7.5, 10 and 12.5 μl, respectively) and sorted by flow cytometry. The rates of non‐viable (FDA+), oriented (OS) and selected spermatozoa (SS), as well as the average sorting rates (SR, sorted spermatozoa/s), were used to determine the sorting efficiency. The effects of the sorting procedure on the quality of sorted spermatozoa were evaluated in terms of total motility (TM), percentage of viable spermatozoa (spermatozoa with membrane and acrosomal integrity) and percentage of spermatozoa with reacted/damaged acrosomes. X‐ and Y‐chromosome‐bearing sperm populations were identified in all of the samples stained with 7.5, 10 and 12.5 μl of H‐42, while these two populations were only identified in 77.5% of samples stained with 5 μl. The values of OS, SS and SR were influenced by the male donor (p < 0.01) but not by the H‐42 concentration used. The quality of sorted sperm samples immediately after sorting was similar to that of fresh samples, while centrifugation resulted in significant reduction (p < 0.05) in TM and in the percentage of viable spermatozoa and a significant increase (p < 0.01) in the percentage of spermatozoa with damage/reacted acrosomes. In conclusion, the sex‐sorting of canine spermatozoa by flow cytometry can be performed successfully using H‐42 concentrations between 7.5 and 12.5 μl. The efficiency of the sorting procedure varies based on the dog from which the sperm sample derives.  相似文献   
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