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In vitro studies of Norwegian Red bovine semen immobilized and cryopreserved in alginate solid gel network 
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下载免费PDF全文 AH Alm‐Kristiansen ER Gaustad G Bai FB Standerholen G Klinkenberg E Kommisrud KE Waterhouse 《Reproduction in domestic animals》2018,53(2):365-370
Development of new semen cryopreservation techniques improving sperm survival and ensuring availability of viable spermatozoa for a prolonged time‐period after AI is promising tools to reduce sensitivity of timing of AI and enhance overall fertility. The SpermVital® technology utilizes immobilization of bull spermatozoa in a solid network of alginate gel prior to freezing, which will provide a gradual release of spermatozoa after AI. The objective of this study was to compare post‐thaw sperm quality and in vitro sperm survival over time of Norwegian Red bull semen processed by the SpermVital® (SV) technology, the first commercialized production line of SpermVital® (C) and by conventional procedure applying Biladyl® extender (B). Post‐thaw sperm motility was not significantly different between SV, C and B semen (p > .05). However, sperm viability and acrosome intactness were higher for SV than C and B semen (p < .05). Small differences in DNA quality were observed (p < .05). Sperm viability after storage in uterus ex vivo was higher for SV than for C semen (p < .05). Furthermore, sperm survival in vitro over time at physiological temperature was significantly higher for SV semen than C semen as well as B semen during the incubation period of 48 hr (p < .05). In conclusion, the SpermVital® technology is improved and is more efficient in conserving post‐thaw sperm quality and results in higher sperm viability over time in vitro for SV than for C and B semen. 相似文献
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Objective To identify farm factors which were associated with reproductive performance in dairy herds in New South Wales.
Procedure A survey was administered by face to face interview to examine the responses of producers drawn from 757 herds, which used the New South Wales Agriculture Department Dairy Herd Improvement scheme. A case-control approach was used to select a total of 126 herds from the first (top group - cases) and fourth quartiles (low group - controls) for intercalving interval.
Results We found that the estimated interval from calving to first mating was significantly different between groups (P = 0.03) and that the groups significantly differed in both their target for interval to first mating (P = 0.02) and their perceived optimum time for first mating (P = 0.04). Other factors associated with a longer intercalving interval included, use of embryo transfer programs (P = 0.08), younger managers (P = 0.02), fewer breedings per day (P = 0.01), a greater number of people detecting heats (P = 0.07), but less hours spent detecting heats while handling the cows (P = 0.11), and a failure to vaccinate bulls for campylobacteriosis (P = 0.14).
Conclusions Managers of herds with poorer reproductive performance did not intend to mate cattle as soon after calving as managers with better reproductive performance, were not as active in seeking veterinary advice on reproduction, and were attempting to treat reproductive diseases and disorders themselves. 相似文献
Procedure A survey was administered by face to face interview to examine the responses of producers drawn from 757 herds, which used the New South Wales Agriculture Department Dairy Herd Improvement scheme. A case-control approach was used to select a total of 126 herds from the first (top group - cases) and fourth quartiles (low group - controls) for intercalving interval.
Results We found that the estimated interval from calving to first mating was significantly different between groups (P = 0.03) and that the groups significantly differed in both their target for interval to first mating (P = 0.02) and their perceived optimum time for first mating (P = 0.04). Other factors associated with a longer intercalving interval included, use of embryo transfer programs (P = 0.08), younger managers (P = 0.02), fewer breedings per day (P = 0.01), a greater number of people detecting heats (P = 0.07), but less hours spent detecting heats while handling the cows (P = 0.11), and a failure to vaccinate bulls for campylobacteriosis (P = 0.14).
Conclusions Managers of herds with poorer reproductive performance did not intend to mate cattle as soon after calving as managers with better reproductive performance, were not as active in seeking veterinary advice on reproduction, and were attempting to treat reproductive diseases and disorders themselves. 相似文献
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Taciana MF Silva Roberio G Olinda Carla MF Rodrigues Ant?nio CL Camara Francisco C Lopes Wesley AC Coelho Múcio FB Ribeiro Carlos IA Freitas Marta MG Teixeira Jael S Batista 《Veterinary research》2013,44(1):1
The present study was aimed at investigating the effect of experimental infection by Trypanosoma vivax in different stages of pregnancy, determining the pathogenesis of reproductive failure, and confirming transplacental transmission. We used 12 pregnant ewes distributed into four experimental groups: G1, was formed by three ewes infected with T. vivax in the first third of pregnancy (30 days); G2 comprised three infected ewes in the final third of pregnancy (100 days); G3 and G4 were composed of three non-infected ewes with the same gestational period, respectively. Each ewe of G1 and G2 was inoculated with 1.25 × 105 tripomastigotes. Clinical examination, determination of parasitemia, serum biochemistry (albumin, total protein, glucose, cholesterol, and urea), packed cell volume (PCV), serum progesterone, and pathological examination were performed. Placenta, amniotic fluid, blood and tissues from the fetuses and stillbirths were submitted to PCR. Two ewes of G1 (Ewe 1 and 3) presented severe infection and died in the 34th and 35th days post-infection (dpi), respectively; but both fetuses were recovered during necropsy. In G2, Ewe 5 aborted two fetuses on the 130th day (30 dpi) of pregnancy; and Ewe 6 aborted one fetus in the 140th day (40 dpi) of gestation. Ewes 2 and 4 delivered two weak lambs that died five days after birth. Factors possibly involved with the reproductive failure included high parasitemia, fever, low PCV, body score, serum glucose, total protein, cholesterol, and progesterone. Hepatitis, pericarditis, and encephalitis were observed in the aborted fetuses. The presence of T. vivax DNA in the placenta, amniotic fluid, blood, and tissues from the fetuses confirms the transplacental transmission of the parasite. Histological lesion in the fetuses and placenta also suggest the involvement of the parasite in the etiopathogenesis of reproductive failure in ewes. 相似文献
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Christopher B. Barrett is a dual Ph. D. candidate in the Department of Agricultural Economics and the Department of Economics, University of Wisconsin, Madison. He is also pursuing a Certificate in African Studies. His previous degrees are from Princeton and Oxford. He spent several years working as a macroeconomist for an international institution, chiefly reporting on and evaluating African structural adjustment programs and debt rescheduling and reduction agreements. 相似文献
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FB Fukushima C Malm M Henry VA Gheller R Serakides MM Neves SP Macedo MS Figueiredo MEJ Andrade MS Chaves MX Silva CMF Rezende EG Melo 《Reproduction in domestic animals》2010,45(6):1059-1064
The aim of this study was to evaluate the distribution of frozen–thawed spermatozoa within the uterine lumen and oviducts following intrauterine laparoscopic deposition at two sites. Twelve bitches of unknown reproductive history were randomly distributed into two groups. Semen (3 ml containing 300 × 106 frozen–thawed spermatozoa) was infused at the uterine body (UB group) or at the cranial tip of the left uterine horn. A 22‐G catheter was used to access the uterine lumen. Sperm cell distribution was evaluated after ovariohysterectomy performed 3 h after artificial insemination (AI). There was no difference between groups in mean time to perform AI. Spermatozoa were detected in all uterine segments, including the tip of both horns, but none was detected in the oviduct. The 22‐G catheter facilitated deposition of semen in the uterine lumen, particularly at the UB site. Sperm cell distribution occurred evenly along both horns, independent of the site of semen deposition. 相似文献
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V Abeles S Harrus J M Angles G Shalev I Aizenberg Y Peres I Aroch 《The Veterinary record》1999,145(5):130-134
Six weimaraner puppies, five of which were genetically related, showed systemic signs associated with hypertrophic osteodystrophy, including fever and involvement of the gastrointestinal, respiratory or nervous systems, in addition to the metaphyseal lesions. In five of the dogs the clinical signs developed less than 10 days after they had been vaccinated with a modified live virus vaccine. Radiographic findings suggested that both the hindlimbs and forelimbs were equally involved in the disease process. Abnormal haematological findings included leucocytosis with neutrophilia and monocytosis, and there was a consistent increase in the activity of alkaline phosphatase. Serum protein electrophoretic studies of three of the dogs revealed hypogammaglobulinaemia and abetaglobulinaemia in two of them. Conservative treatment with rest and non-steroidal anti-inflammatory drugs had little effect, and treatment with corticosteroids appeared to give the best results. 相似文献
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S(+) ketamine, one of the two enantiomers of racemic ketamine, is a phencyclidine derivative that induces amnesia and analgesia. Its activity is related to blockade of NMDA receptors and some opioid action. We compared anesthetic induction and recovery quality with S(+) ketamine in combination with diazepam or midazolam in 10 dogs (ASA 1) admitted for elective surgery. After all clinical examinations, the dogs were separated into two groups (G I and G II). All animals received acepromazine (0.1 mg kg?1) and fentanyl (5 µg kg?1) IM, 20 minutes before induction with S(+) ketamine (6 mg kg?1) and diazepam (0.5 mg kg?1) IV (G I) or midazolam 0.2 mg kg?1 (G II) IV. The doses of diazepam and midazolam were chosen according to the literature. All dogs were intubated and then maintained with halothane in oxygen at a vaporizer setting sufficient to maintain surgical anesthesia. Quality of induction, time needed for intubation, heart rate, respiratory rate, SpO2, time to extubation, and quality of recovery were evaluated. The results were analyzed by Student's t‐test. Smooth induction and recovery were observed in all animals. The time to intubation was 45 ± 20 (GI) and 25 ± 6 seconds (GII), HR was 122 ± 12 (GI) and 125 ± 7 beats minute?1 (GII), RR was 17 ± 2 (GI) and 21 ± 3 breaths minute?1 (GII), SpO2 was 96 ± 2 (GI) and 94 ± 1% (GII), time to extubation was 7 ± 3 (GI) and 4 ± 1 minutes (GII). No statistical differences were found in analyses, although time to intubation was less in GII. The results suggested that both combinations could be used safely for anesthetic induction in healthy dogs. 相似文献