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21.
The transition period is a critical time for dairy cows as the animal is subjected to the physiological stress accompanying parturition. Immunosuppression and health status were examined during this period in 80 Holstein cows. Blood samples were taken from each cow 3, 2 and 1 week before and after calving, and at calving (0 day). RNA was extracted and subjected to real‐time PCR to determine mRNA levels for the immune‐related genes TLR 2, 4, 6, 7 and β‐defensin 5 in addition to the reproduction‐related genes prolactin and IGF‐I. Results showed significant up‐regulation of pro‐inflammatory‐selected genes, TLR 4, 6 7 and β‐defensin 5 at the third‐week post‐calving; however, earlier periods had lower expression of such genes. In contrast, the immunosuppression biomarker TLR2 gene was up‐regulated at calving and 1 week after parturition and then down‐regulated again at second and third week. Prolactin and IGF‐I genes expression levels were significantly and gradually increased mainly post‐partum. This research highlights that the expression patterns of TLRs, BNBD5, PRL and IGF‐I could be biomarkers to follow up immune and reproductive status of dairy cow at peri‐parturient period to predict the most susceptible risk time for disease incidence and to build up management protocol.  相似文献   
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Triplicate groups of pike perch (Sander lucioperca) juveniles were fed six experimental diets containing protein levels varying from 263 to 619 g kg−1 dry matter (d.m.) for 56 days. Dietary protein was supplied by graded amounts of fish meal (with 720 g kg−1 crude protein). Crude lipid and gross energy content of 101–107 g kg−1 and 19.9–20.6 MJ kg−1 remained constant between experimental diets. Pike perch with an initial body weight of 1.05 ± 0.05 g were randomly distributed in 18 tanks of two similar recirculation systems and fed on gradually decreasing feeding rates of 10 to 6% of their body weight per day. Growth performance and feed conversion increased with dietary protein level from 263 to 549 g kg−1 d.m. but did not decline at highest dietary protein level. Protein efficiency ratio declined linearly with increasing dietary protein. Survival ranged between 89.7 and 93.9% and was not affected by dietary composition. Dry matter and crude lipid content of pike perch fingerlings decreased with increasing dietary protein supply and significantly the lowest dry matter and crude lipid levels were observed in fish fed diets containing 619 g kg−1 of crude protein. The dietary protein requirement for pike perch fingerlings calculated by broken‐line and second‐order polynomial regression ranged between 529 and 577 g kg−1, respectively.  相似文献   
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Sheep scab is an intensively pruritic, exudative and allergic dermatitis of sheep caused by the ectoparasitic mite Psoroptes ovis. The purpose of the present study was to investigate the effect of P. ovis infestation on different components of the ovine epidermal barrier within the first 24 hours post-infestation (hpi). To achieve this, the expression of epidermal differentiation complex (EDC) genes and epidermal barrier proteins, the nature and severity of epidermal pathology and transepidermal water loss (TEWL) were evaluated.By 1 hpi a significant dermal polymorphonuclear infiltrate and a significant increase in TEWL with maximal mean TEWL (598.67 g/m2h) were observed. Epidermal pathology involving intra-epidermal pustulation, loss of epidermal architecture and damage to the basement membrane was seen by 3 hpi. Filaggrin and loricrin protein levels in the stratum corneum declined significantly in the first 24 hpi and qPCR validation confirmed the decrease in expression of the key EDC genes involucrin, filaggrin and loricrin observed by microarray analysis, with 5.8-fold, 4.5-fold and 80-fold decreases, respectively by 24 hpi.The present study has demonstrated that early P. ovis infestation disrupts the ovine epidermal barrier causing significant alterations in the expression of critical barrier components, epidermal pathology, and TEWL. Many of these features have also been documented in human and canine atopic dermatitis suggesting that sheep scab may provide a model for the elucidation of events occurring in the early phases of atopic sensitisation.  相似文献   
25.

Background

The risk of injuries is of major concern when keeping horses in groups and there is a need for a system to record external injuries in a standardised and simple way. The objective of this study, therefore, was to develop and validate a system for injury recording in horses and to test its reliability and feasibility under field conditions.

Methods

Injuries were classified into five categories according to severity. The scoring system was tested for intra- and inter-observer agreement as well as agreement with a ''golden standard'' (diagnosis established by a veterinarian). The scoring was done by 43 agricultural students who classified 40 photographs presented to them twice in a random order, 10 days apart. Attribute agreement analysis was performed using Kendall''s coefficient of concordance (Kendall''s W), Kendall''s correlation coefficient (Kendall''s τ) and Fleiss'' kappa. The system was also tested on a sample of 100 horses kept in groups where injury location was recorded as well.

Results

Intra-observer agreement showed Kendall''s W ranging from 0.94 to 0.99 and 86% of observers had kappa values above 0.66 (substantial agreement). Inter-observer agreement had an overall Kendall''s W of 0.91 and the mean kappa value was 0.59 (moderate). Agreement for all observers versus the ''golden standard'' had Kendall''s τ of 0.88 and the mean kappa value was 0.66 (substantial). The system was easy to use for trained persons under field conditions. Injuries of the more serious categories were not found in the field trial.

Conclusion

The proposed injury scoring system is easy to learn and use also for people without a veterinary education, it shows high reliability, and it is clinically useful. The injury scoring system could be a valuable tool in future clinical and epidemiological studies.  相似文献   
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The aim of this study was to determine the optimal maturation culture period of ovum pick up (OPU)‐derived cumulus oocytes complexes (COCs) in relation to their developmental capacity. Embryo production, embryo cryotolerance, post‐transfer embryonic survival and calf characteristics such as gestation length, birthweight and sex ratio were investigated. This retrospective study covers the analyses of ovum pick up –in vitro production and calving results from a commercial programme that took place between March 1994 and September 2004. Donors were both heifers (of which approximately 90% pregnant) and cows (of which approximately 10% pregnant). Embryo production analyses were based on 7800 OPU sessions conducted from January 1995 until January 1999. Analyses of calving rate were based on 13 468 embryo transfers performed during January 1995 until May 2002. Analyses on calf characteristics were based on 2162 calves born between March 1994 and September 2004. The in vitro maturation culture period ranged from 16 to 28 h. The mean production rate of transferable embryos was 16.5% (1.2 embryos per OPU session). Length of maturation culture period did not affect the production of transferable embryos. Mean calving rate was 40.9% and 38.7% for fresh and frozen/thawed embryos, respectively. Calving rate was not affected by the maturation culture period. Mean birthweight, gestation length and proportion of male calves were 46 kg, 281.9 days and 52.8%, respectively. Maturation culture period did not affect these variables. In conclusion, this study shows that the in vitro maturation culture period within the range of 16–28 h does not affect in vitro embryo production, embryo cryotolerance, post‐transfer embryonic survival and calf characteristics, suggesting that all COC batches collected by OPU on the same day, can be fertilized in one IVF session without a significant loss in the production from oocyte to calf.  相似文献   
27.
The objective of this study was to examine the effect of various growth factors such as the epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I) either individually or in association, in the presence of follicle-stimulating hormone (FSH) on the in vitro growth and viability of caprine oocytes at pre-antral stage. Pre-antral follicles were disassociated enzymatically and mechanically from pre-pubertal caprine ovaries after the animals were anaesthetically ovariectomized. Caprine pre-antral follicles in group 1, 2, 3 and 4 were cultured in growth culture medium, growth culture medium + EGF, growth culture medium + IGF-I and growth culture medium + IGF-I + EGF, respectively, for 9 days. The results indicated that EGF (50 mg/l) increased the survival rate of oocytes, but decreased the growth rate of oocytes; IGF-I (100 mg/l) effectively maintained the survival of oocytes and stimulated their growth; IGF-I (100 mg/l) and EGF (50 mg/l) in combination produced a higher effect on both the survival and the growth rate of oocytes than IGF-I or EGF alone. Conclusively, the growth factors can effectively maintain the survival of caprine oocytes from pre-antral follicles and regulate their growth in culture. EGF and IGF-I in association could synergically meliorate the culture system of caprine pre-antral follicles.  相似文献   
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ObjectiveTo assess oxygenation, ventilation‐perfusion (V/Q) matching and plasma endothelin (ET‐1) concentrations in healthy horses recovering from isoflurane anaesthesia administered with or without pulse‐delivered inhaled nitric oxide (iNO).Study DesignProspective experimental trial.AnimalsHealthy adult Standardbred horses.MethodsHorses were anaesthetized with isoflurane in oxygen and placed in lateral recumbency. Six control (C group) horses were anaesthetized without iNO delivery and six horses received pulse‐delivered iNO (NO group). After 2.5 hours of anaesthesia isoflurane and iNO were abruptly discontinued, inhaled oxygen was reduced from 100% to approximately 30%, and the horses were moved to the recovery stall. At intervals during a 30‐minute period following the discontinuation of anaesthesia, arterial and mixed venous blood gas values, shunt fraction (Qs/Qt), plasma ET‐1 concentration, pulse rate and respiratory rate were measured or calculated. Repeated measures anova and a Bonferroni post hoc test was used to analyze data with significance set at p <0.05.ResultsAt all time points in the recovery period, NO horses maintained better arterial oxygenation (oxygen partial pressure: NO 13.2 ± 2.7–11.1 ± 2.7 versus C 6.7 ± 1.1–7.1 ± 1.1 kPa) and better V/Q matching (Qs/Qt NO 0.23 ± 0.05–0.14 ± 0.06 versus C 0.48 ± 0.03–0.32 ± 0.08%) than C horses. Mixed venous oxygenation was higher in NO for 25 minutes following the discontinuation of anaesthesia (NO 6.3 ± 0.2–4.5 ± 0.07 versus C 4.7 ± 0.6–3.7 ± 0.3 kPa). In both groups of horses arterial oxygenation remained fairly stable; venous oxygenation declined over this time period in the NO group but still remained higher than venous oxygen in the C group. ET‐1 concentrations were higher at most time points in C than NO. Changes in other parameters were either minor or absent.Conclusions and Clinical RelevanceDelivery of iNO to healthy horses during anaesthesia results in better arterial and venous oxygenation and V/Q matching (as determined by lower Qs/Qt) and lower ET‐1 concentrations throughout a 30‐minute anaesthetic recovery period.  相似文献   
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本文评估了沙棘叶水提物在大白鼠体内的适应原活性和毒性.提取物的剂量依赖性适应原活性的研究采取将小鼠置于低温(5℃),低压(428mmHg),抑制(C-H-R)的环境下的30min前口服不同剂量的沙棘叶水提物.在亚急性毒性中,连续14d每天口服10倍和20倍最大有效剂量(每天口服1g/kg体重和2g/kg体重)和连续30...  相似文献   
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