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91.
Challenges in Pig Artificial Insemination 总被引:4,自引:0,他引:4
J Roca JM Vázquez MA Gil C Cuello I Parrilla EA Martínez 《Reproduction in domestic animals》2006,41(S2):43-53
92.
Vilhelmiina Huuskonen JM Lynne Hughes Elisa Estaca Bañon Eleanor West 《Veterinary anaesthesia and analgesia》2013,40(1):74-82
ObjectiveTo investigate whether intratesticular injection of lidocaine pre-surgery would reduce the intraoperative responses to elective castration in dogs.Study designDouble-blinded, randomized, controlled, prospective clinical study.AnimalsForty-two client-owned dogs weighing 2.2–38.4 kg and aged between 4.5 and 56 months.MethodsGroup L dogs received an intratesticular injection of 2% lidocaine (2 mg kg?1) and Group S an identical volume of saline prior to surgery. Premedication was with acepromazine and morphine intramuscularly. Anaesthesia was induced with propofol intravenously and maintained with isoflurane vaporized in oxygen. Heart rate (HR), mean arterial pressure (MAP), respiratory rate (fR), end-tidal isoflurane (Fe′ISO) and carbon dioxide concentrations, oxygen saturation and ECG were monitored during surgery. Fe′ISO was maintained at 1.0 ± 0.1%. Supplemental propofol was given in response to gross movement.ResultsGroup L had significantly lower maximum values for both HR and MAP. Group L displayed significantly smaller increases in HR during exteriorization of the first testis than Group S. There was an overall significant difference in MAP between groups during all surgical events (p = 0.041) and time points (p = 0.002). In univariate analysis, Group L showed significantly less changes in MAP during skin incision, exteriorization of the first testis and clamping of both spermatic cords. Group S reached its highest fR significantly earlier. Group L (eight dogs) required additional propofol 33 ± 18 minutes after the start of surgery and Group S (seven dogs) at 19 ± 17 minutes; this difference was not statistically significant. Seven dogs in Group L and 12 dogs in Group S required rescue analgesia with morphine (GCMPS-SF score ≥6); this difference was not statistically significant. No adverse effects were reported postoperatively.Conclusions and clinical relevanceBased on this study, the authors recommend the use of intratesticular lidocaine for surgical castration in dogs. 相似文献
93.
IB Lima‐Verde A Johannisson T Ntallaris E Al‐Essawe Z Al‐Kass T Nongbua F Dórea N Lundeheim K Kupisiewicz A Edman JM Morrell 《Reproduction in domestic animals》2018,53(1):127-136
Traditionally, extenders for bull semen included egg yolk or milk, but recently there has been a move to avoid material of animal origin. The aim of this study was to evaluate the effects of two commercial extenders (based on soya lecithin and liposomes) on bull sperm quality after cryopreservation. Post‐thaw sperm quality was evaluated by computer‐assisted sperm analysis and flow cytometric assessment of membrane integrity, chromatin integrity, mitochondrial membrane potential, production of reactive oxygen species and tyrosine phosphorylation. Furthermore, an artificial insemination (AI) trial was conducted, and 56‐day non‐return rates were evaluated. Semen frozen in the liposome‐based extender showed similar membrane integrity and higher mitochondrial membrane potential compared to those in the soya lecithin‐based extender. Chromatin integrity and production of live H2O2+ reactive oxygen species were similar in both extenders. Less superoxide was produced in the samples extended with liposome‐based extender, with or without menadione stimulation. Chromatin integrity and tyrosine phosphorylation were not affected by either type of extender. No differences in 56‐day non‐return rate between extenders containing soya lecithin and liposomes were observed in the AI trial (66% ± 0.8 and 65% ± 0.8, respectively). In conclusion, the sperm quality of bull semen frozen in the two extenders that do not contain material of animal origin was similar, although the semen frozen in the liposome‐based extender had higher mitochondrial membrane potential. Either extender could be used in situations where extenders containing material of animal origin are to be avoided. 相似文献
94.
SUMMARY The milk production of cows after induced parturition was compared with that of non-induced cows with similar calving dates, in 37 winter-calving, pasture-fed, commercial dairy herds in south-western Victoria. Parturition was induced when most cows were between 27 and 35 weeks of pregnancy. Milk production was compared for the lactation that commenced immediately after induction. The percentage of cows whose lactations were terminated less than 120 days after calving was increased by induction. Mean percentages for untreated and induced groups were 3.0% and 5.4%, respectively . For cows with lactations of at least 120 days duration, lactation length was not affected by the prior induction of parturition. However, milk production during the subsequent lactation was 9.0% less in induced groups. Fat and protein concentrations were not substantially affected. The reduction in milk production was not affected by stage of pregnancy when cows were induced, but tended to be greater in herds that delayed milking of induced cows . 相似文献
95.
A total of 6195 cattle were enrolled in this observational study. Serum antibody concentrations to bovine herpesvirus 1 (BHV1) and bovine viral diarrhoea virus (BVDV) were measured at entry to and exit from backgrounding facilities to assess their statuses on arrival and the extent of seroconversion to these viruses during backgrounding. The backgrounding facilities were contiguous with five feedlots in: Queensland (two sites), New South Wales, South Australia and Western Australia. Cattle were held in the backgrounding facilities for a minimum of 29 days and a median of 34 days. On backgrounding facility entry, 32.7% of the study population was seronegative to BVDV, but 85.7% was seronegative to BHV1. After commingling in the backgrounding facilities, of the cattle that were seronegative on backgrounding facility entry, 33.9% and 30.3% showed a serological increase to BVDV and BHV1, respectively. At backgrounding facility exit, when cattle were placed in their feedlots, 19.6% and 59.1% were seronegative to BVDV and BHV1, respectively, and 0.26% were persistently infected with BVDV. There was a strong association between seroincrease to BVDV and seroincrease to BHV1 (P = 0.005) at animal level in cohorts known to contain an animal persistently infected with BVDV. 相似文献
96.
JP Anchordoquy JM Anchordoquy MA Sirini G Mattioli SJ Picco CC Furnus 《Reproduction in domestic animals》2013,48(6):905-911
Manganese (Mn) is a trace element present in forages and cereals, and its concentration depends on soil status. Manganese deficiency in cattle, goats and ewes not only impairs oestrous cycle but reduces calf birth weight. The achievement of the first oestrus is delayed, and more attempts are necessary to obtain a successful conception. This study was conducted to investigate the effect of the availability of supplemental Mn during IVM on DNA damage of cumulus cells and total glutathione (GSH) content in oocytes and cumulus cells. The effect of supplementary Mn during IVM on subsequent embryo development was also studied. The results reported here indicate (i) DNA damage in cumulus cells decreased with 0, 2, 5 and 6 ng/ml Mn supplementation during IVM (p < 0.05). (ii) Intracellular GSH‐GSSG content increased (p < 0.01) with different Mn concentrations in oocytes and cumulus cells. Also, cumulus cell number per cumulus oocyte‐complexes (COC) did not differ either before or after IVM. (iii) Addition of Mn to maturation medium resulted in similar cleavage rates (p > 0.05) at 0, 2, 5 and 6 ng/ml Mn. However, subsequent embryo development to blastocyst stage was significantly higher (p < 0.01) in oocytes matured with 5 and 6 ng/ml Mn. (iv) There was also an increase (p < 0.05) in mean cell number per blastocyst obtained from oocytes matured with 5 and 6 ng/ml respect to zero Mn (IVM alone) and 2 ng/ml Mn. This study provides evidence that optimal embryo development to the blastocyst stage was partially dependent on the presence of Mn during IVM. Moreover, the availability of Mn during oocyte maturation ensures ‘normal’ intracellular GSH content in COCs and protects DNA integrity of cumulus cells. 相似文献
97.
AIM: To describe the accuracy of transrectal ultrasonography for predicting calving dates in dairy cows under typical New Zealand conditions and to assess potential risk factors for differences between predicted and actual calving dates.METHODS: Data were collected from 116 seasonally calving herds over 2 years in a retrospective single cohort study. Transrectal ultrasonography was undertaken by experienced veterinarians (n=12) to determine if cows were pregnant, and if so to estimate fetal age. Predicted calving date was calculated by adding 282 days to the estimated conception date. Accuracy was assessed using differences between predicted and actual calving dates for each animal. Potential risk factors for animals calving >10 days before or after their predicted calving date were assessed using multinomial logistic regression models.RESULTS: The study population comprised 83,104 cows over the 2 years of the study; 75,037 (90.3%) cows calved within 10 days of their predicted calving date, 3,683 (4.4%) calved >10 days earlier, and 4,384 (5.3%) >10 days later, than predicted. Risk factors for calving >10 days before or after the predicted calving date included having >1 artificial insemination (AI) before pregnancy diagnosis (p=0.03), where the cow’s most recent AI was <21 days before the end of the herd’s AI period (p<0.01), and where the diagnosis was made at the second or third herd-visit (p<0.01). The probability of calving being >10 days later than predicted also increased when the fetus was ≥13 weeks old at pregnancy diagnosis (p<0.01).CONCLUSIONS AND CLINICAL RELEVANCE: In this study, >90% of cows diagnosed pregnant by veterinarians using transrectal ultrasonography calved within 10 days of the predicted calving date. In herds where herd reproductive performance is high, it would be expected that more cows would conceive to their first AI, and potentially fewer cows would have AI close to the end of the herd’s AI period, which would increase diagnostic accuracy. Where herd managers rely on accurate predicted calving dates they should be informed about realistic expected accuracy. For greatest accuracy, a complete AI history should be made available to the person performing the pregnancy diagnoses and cows at most risk of having inaccurate predicted calving dates should be identified. 相似文献
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