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1.
OBJECTIVE: To determine efficacy of vaccines incorporating QuilA, alum, dextran combined with mineral oil, or Freund adjuvant for immunization of feedlot cattle against Streptococcus bovis and Lactobacillus spp. ANIMALS: 24 steers housed under feedlot conditions. PROCEDURE: Steers were randomly assigned to 4 experimental groups and a control group. Animals in experimental groups were inoculated on days 0 and 26 with vaccines containing Freund adjuvant (FCA), QuilA, dextran combined with mineral oil (Dex), or alum as adjuvant. Serum anti-S bovis and anti-Lactobacillus IgG concentrations were measured, along with fecal pH, ruminal fluid pH, and number of S bovis and Lactobacillus spp in ruminal fluid. RESULTS: Throughout the study, serum anti-S bovis and anti-Lactobacillus IgG concentrations for animals in the Dex, QuilA, and alum groups were similar to or significantly higher than concentrations for animals in the FCA group. Serum anti-S bovis and anti-Lactobacillus IgG concentrations were significantly increased on days 26 through 75 in all 4 experimental groups, and there was a linear relationship between anti-S bovis and anti-Lactobacillus IgG concentrations. For animals in the QuilA and Dex groups, mean pH of feces throughout the period of experiment were significantly higher and numbers of S bovis and Lactobacillus spp in ruminal fluid on day 47 were significantly lower than values for control cattle. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that immunization of feedlot steers against S bovis and Lactobacillus spp with vaccines incorporating Freund adjuvant, QuilA, dextran, or alum as an adjuvant effectively induced high, long-lasting serum anti-S bovis and anti-Lactobacillus IgG concentrations. Of the adjuvants tested, dextran may be the most effective.  相似文献   
2.
The objective of this study was to characterize follicular dynamics in pre-pubertal, pubertal and post-pubertal periods, as well as the effect of high-energy intake on follicular development and age at puberty in heifers. Thirty-one Nelore (Bos indicus) heifers, 6 months old, were randomly assigned to receive two different diets: one of low (GI) and other of high dietary energy intake (GII). Animals were evaluated in relation to body weight gain by being weighed every 21 days. Heifers were evaluated every other day by real-time linear ultrasonography to characterize ovarian structures development from weaning to post-pubertal period. Blood samples were collected to determine plasmatic concentrations of progesterone by RIA method. The ovulation was determined when progesterone concentrations were >1 ng/mL in three consecutive samples, and by ultrasound images of corpus luteum; and oestrous behaviour in some animals. Age at puberty differed among heifers of GII (17.00 +/- 0.46 months) compared with heifers of GI (19.87 +/- 0.47 months; p < or = 0.05). Maximum size of the dominant follicles at pre-pubertal period was greater in GII heifers than in GI (10.52 +/- 0.33 and 9.76 +/- 0.15 mm, respectively; p < or = 0.05). As heifers approached first ovulation time, size of dominant follicle increased (11.75 +/- 0.37 mm for GI and 12.52 +/- 0.91 mm for GII; p < or = 0.05). Body weight at puberty was not different in both groups (302.33 +/- 27.31 kg for GI and 326.19 +/- 27.78 kg for GII heifers; p > 0.05). We conclude that animals receiving high dietary energy intake attained the puberty earlier and the development of follicles were different than in low dietary energy intake.  相似文献   
3.
Expression of Kit ligand (KL) and insulin‐like growth factor binding protein (IGFBP3) genes was studied at different in vivo and corresponding in vitro stages of development of the ovarian follicles in sheep. The expression of both KL and IGFBP3 was significantly higher in the primordial follicles relative to any other stage of development. Compared to the other stages, the KL expression in the cumulus cells from in vivo grown large antral follicles and that of IGFBP3 in COCs’ isolated from large antral follicles matured in vitro for 24 hr were significantly higher. In the oocytes from in vivo grown ovarian follicles, the expression of KL was the same at all the stages of development. Insulin‐like growth factor binding protein 3 expression was also the same in the oocytes at all the stages of the development except for a significantly lower expression in those from antral follicles. The expression of KL in the cumulus cells decreased significantly in the in vitro grown early antral follicles but did not change further as the development progressed. The expression of IGFBP3 in the cumulus cells from in vitro grown ovarian follicles appeared to increase as the development progressed although the increase was not significant between any two consecutive stages of development. In the oocytes in in vitro grown ovarian follicles, the expression levels of KL and IGFBP3 genes did not change with development. It is concluded that (i) KL and IGFBP3 genes follow specific patterns of expression during ovarian folliculogenesis and (ii) in vitro culture of preantral follicles compromises the development potential through alterations in the stage‐specific patterns of expression of these and other developmentally important genes.  相似文献   
4.
K-agglutination, pilus-enzyme-linked immunosorbent assay (ELISA) and outer membrane protein-ELISAs were used to assess humoral responses after vaccination with a commercial, multivalent, ovine foot rot vaccine (Dichelobacter nodosus whole cells) in three groups of nine-month-old lambs of markedly different bodyweight, nutritional history and dietary protein supply. Mean bodyweights of lambs in low (L), medium (M) and high (H) bodyweight/nutrition groups were 22, 32 and 48 kg, respectively, at the time of vaccination. Few significant differences in humoral responses to vaccine antigens were found between groups. However, lambs in group H tended to have lower levels of antibody to a greater number of component antigens than did lambs in the other groups. These results suggest that low bodyweight due to poor nutrition is unlikely to affect the response of sheep to multivalent foot rot vaccines.  相似文献   
5.
Studies have demonstrated the importance of mitochondria to sperm functionality, as the main source of ATP for cellular homoeostasis and motility. However, the role of mitochondria on sperm metabolism is still controversial. Studies indicate that, for some species, glycolysis may be the main mechanism for sperm energy production. For ram sperm, such pathway is not clear. Thus, we evaluated ram sperm in response to mitochondrial uncoupling and glycolysis inhibition aiming to assess the importance of each pathway for sperm functionality. Statistical analysis was performed by the SAS System for Windows, using the General Linear Model Procedure. Data were tested for residue normality and variance homogeneity. A p < .05 was considered significant. Groups treated with the mitochondrial uncoupler Carbonyl cyanide 3 chlorophenylhydrazone (CCCP) showed a decrease in the percentage of cells with low mitochondrial activity and high mitochondrial membrane potential. We also observed that the highest CCCP concentration promotes a decrease in sperm susceptibility to lipid peroxidation. Regardless the lack of effect of CCCP on total motility, this substance induced significant alterations on sperm kinetics. Besides the interference of CCCP on spermatic movement patterns, it was also possible to observe such an effect in samples treated with the inhibitor of glycolysis (2‐deoxy‐d ‐glucose, DOG). Furthermore, treatment with DOG also led to a dose‐dependent increase in sperm susceptibility to lipid peroxidation. Based on our results, we suggest that the glycolysis appears to be as important as oxidative phosphorylation for ovine sperm kinetics as this mechanism is capable of maintaining full motility when most of the cells have a low mitochondrial membrane potential. Furthermore, we found that changes in the glycolytic pathway trough glycolysis inhibition are likely involved in mitochondrial dysfunction and sperm oxidative unbalance.  相似文献   
6.
Background: The rumen wall plays a major role in efficient transfer of digested nutrients in the rumen to peripheral tissues through the portal venous system. Some of these substrates are metabolised in the epithelium during this process. To identify the specific proteins involved in these processes, we used proteomic technologies. Protein extracts were prepared from ventral rumen tissue of six sheep fed a fibrous diet at 1.5× maintenance energy requirements.Using a newly developed method, we were able to enzymatically isolate the epithelial cells from underlying tissue layers, thus allowing cytosol and membrane fractions to be independently analysed using liquid chromatography tandem mass spectrometry(LC MS/MS).Results: Using our procedure we identified 570 epithelial proteins in the Ovis aries sequence database. Subcellular locations were largely cytosolic(n = 221) and extracellular(n = 85). However, a quarter of the proteins identified were assigned to the plasma membrane or organelle membranes, some of which transport nutrients and metabolites. Of these 91 were transmembrane proteins(TMHMM), 27 had an N-terminal signal peptide(signalP) and TMHMM motif,13 had a glycosylphosphatidylinositol(GPI) anchor and signalP sequence, 67 had beta(β) strands or 17 β strands and a transit peptide sequence, indicating the identified proteins were integral or peripheral membrane proteins. Subunits of the 5 protein complexes involved in mitochondrial cellular energy production were well represented. Structural proteins(15%), proteins involved in the metabolism of lipids and proteins(26%) and those with steroid or cytokine action were a feature of the proteome.Conclusion: Our research has developed a procedure to isolate rumen epithelium proteins from the underlying tissue layers so that they may be profiled using proteomic technologies. The approach improves the number of proteins that can be profiled that are specific to the epithelium of the rumen wall. It provides new insights into the proteins of structural and nutritional importance in the rumen epithelium, that carry out nutrient transport and metabolism, cell growth and signalling.  相似文献   
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8.
At high altitude, hypoxia and/or oxidative stress may compromise fertility. This study tested the relative effect of short‐ or long‐term exposure to high‐altitude hypobaric hypoxia and oxidative stress in sheep on preovulatory follicle dynamics and gonadotrophin secretion. Thus, growth dynamics, stereidogenic function and competence to ovulate of preovulatory follicles, as well as FSH and LH availability throughout the entire oestrous cycle, were compared among sheep native from low and high altitude, and sheep newcomers to high altitude. The results indicates that short‐term exposure in sheep newcomers to high altitude has a deleterious effect on both the ovarian function (affecting preovulatory follicular development) and the pituitary function (diminishing plasma LH availability). On the other hand, there were no detected differences in the preovulatory follicular development in sheep adapted to high altitude for generations and, conversely, LH secretion was increased, which suggests an adaptive mechanism. The treatment with antioxidant agents during a relative short period for the time of folliculogenesis (approximately 1 month and a half) changed substantially the development of preovulatory follicles in short‐term exposed sheep to similar patterns than in sheep native and living to both high and low altitude. These results highlight the role of oxidative stress in the detriment of the reproductive function in individuals recently exposed to high‐altitude hypoxic environment.  相似文献   
9.
Our aim was to compare Corpus luteum (CL) development and blood plasma concentration of progesterone ([P4]) in thoroughbred mares after spontaneous (Control: C) or human chorionic gonadotrophin (hCG)‐induced ovulation. Lactating mares (C = 12; hCG = 21) were daily teased and mated during second oestrus post‐partum. Treated mares received 2500 IU hCG i.v. at first day of behavioural oestrus when dominant follicular size was >35, ≤42 mm and mated 12–24 h after. Control mares in oestrus were mated with dominant follicular size ≥45 mm. Dominant follicle before ovulation, CL and gestational sac were measured by ultrasound and [P4] by radioimmunoassay (RIA). Blood sampling and ultrasound CL exams were done at days 1, 2, 3, 4, 8, 12, 16, 20, 25, 30, 35, 40, 45, 60 and 90 after ovulation and gestational sac from day 12 after ovulation in pregnant (P) mares; non‐pregnant (NP) were followed until oestrus returned. Data analyses considered four subgroups: hCG‐P, hCG‐NP, C‐P and C‐NP. Preovulatory follicular size was smaller in hCG mares than in C: 39.2 ± 2.7 mm vs 51.0 ± 1.8 mm (p < 0.0001). All hCG mares ovulated 24–48 h after treatment and presented similar oestrus duration as controls. C. luteum size in P mares showed the same pattern of development through days 4–35, presenting erratic differences during initial establishment. Thus, on days 1 and 3, CL was smaller in hCG‐P (p < 0.05); while in hCG‐NP, CL size was greater than in C‐NP on day three (p = 0.03). Corpus luteum size remained stable until day 90 in hCG‐P mares, while in C‐P a transient and apparently not functional increase was detected on days 40 and 45 (p < 0.05) and the decrease from day 60 onwards, made this difference to disappear. No differences were observed in [P4] pattern between P, or between NP subgroups, respectively. So, hCG‐induced ovulation does not affect CL development, neither [P4] during early pregnancy. One cycle pregnancy rate tended to be lower in hCG mares while season pregnancy rates were similar to controls.  相似文献   
10.
The objective of this work was to describe the presence of osteopontin (OPN) in canine seminal plasma and sperm membranes. A pool of seminal plasma and sperm membrane extract from 30 dogs was used. Polyacrylamide electrophoresis gels were performed and the bands were transferred to nitrocellulose paper and Western blot was undertaken using an antibody anti-OPN. Two and 12 bands were marked in the seminal plasma (77.2 and 15.6 kDa) and sperm membrane extracts (70.6–26.6 kDa), respectively. However, from 12 marked bands in the sperm membrane extract, only three (46.4, 37.7 and 36.5 kDa) were strongly marked. We conclude that, seminal plasma and sperm membranes from dogs contain different isoforms of OPN; yet, further studies will be necessary to determine their function in this species.  相似文献   
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