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31.
32.
A screen house experiment was undertaken to study effect of time of application of deoiled castor cake on the yield, N and P uptake by wheat crop. The results indicate that the wheat growth decreased significantly with increasing dose of castor cake, when castor cake was applied just before sowing of wheat. When castor cake was applied 10 days before wheat sowing, the dry matter yield (DMY) of wheat increased up to 0.125% dose of castor cake and reduced thereafter. But when the castor cake was applied 20 days before wheat sowing, the DMY was at par under all the doses of castor cake and better than control indicating the degradation of the toxicants produced by the castor cake. Application of castor cake can also be helpful in reducing the cost of phosphatic fertilizer. Thus it can be concluded that castor cake should be applied at least 3 weeks before sowing of the crop and keeping the field moist for degradation of the toxicants.  相似文献   
33.
The purpose of this study was to evaluate different parameters of the immune status in the mare, during the follicular and the luteal phases of the oestrous cycle, in two consecutive years. Functional competence of peripheral blood neutrophils, such as chemotaxis, phagocytosis and oxidative burst was assessed under physiological cyclic conditions (Exp. I). In the second year of this study (Exp. II), besides peripheral blood neutrophil phagocytosis and oxidative burst analysis, circulating lymphocyte subsets were also characterized. The reproductive status in a total of 17 adult cycling mares was evaluated by ultrasonography and further confirmed by plasma progesterone levels. Chemotaxis tests were performed using porous membranes inserted in transwell chambers. Lipopolysaccharide (LPS) from Escherichia coli and N‐formyl‐Met‐Leu‐Phe (fMLP) were used as chemoattractants. Measurement of phagocytosis and oxidative burst in blood neutrophils were assessed by flow cytometry using commercially available kits. Quantification of T‐lymphocyte subsets was assessed by indirect immunofluorescence staining after incubation with monoclonal antibodies specific for CD2, CD3, CD4 and CD8 cell markers by flow cytometry. Natural killer cells and B cells were estimated mathematically. No significant difference was found in migration, phagocytosis and oxidative burst at either phase of the oestrous cycle. Statistical analysis of total white blood cell counts also showed no significant difference between either phase of the oestrous cycle, although there was a tendency for blood neutrophils to increase in number under the progesterone influence (p = 0.09). Lymphocytic subpopulations did not differ throughout the oestrous cycle. Overall, our results suggest that luteal and follicular phases in cycling mares may not influence the immune status of the mare.  相似文献   
34.
Post-bloom gibberellin sprays increased fruit length:diameter (L/D) ratio and juice soluble solids but did not influence flesh firmness of ‘Golden Delicious’ apples grown in a maritime (Québec) or desert (Okanagan Valley, B.C.) climate. Irrespective of GA treatment, ‘exterior’ fruit at both Canadian locations was larger, yellower, exhibited less russet, and contained more soluble solids at harvest than ‘interior’ fruit. Fruit shape (L/D ratio) was not influenced by position of the fruit within the canopy. Correlation analyses showed that surface russet development is poorly related to seed set, fruit size and other measures of fruit quality. However, a correlation matrix examining the degree of interrelatedness of all fruit size, fruit development and fruit quality indices revealed other relationships that may provide clues to understanding the relationship between fruit growth and quality development of ‘Golden Delicious’ apple.  相似文献   
35.
The Global Oscillation Network Group (GONG) project estimates the frequencies, amplitudes, and linewidths of more than 250,000 acoustic resonances of the sun from data sets lasting 36 days. The frequency resolution of a single data set is 0.321 microhertz. For frequencies averaged over the azimuthal order m, the median formal error is 0.044 microhertz, and the associated median fractional error is 1.6 x 10(-5). For a 3-year data set, the fractional error is expected to be 3 x 10(-6). The GONG m-averaged frequency measurements differ from other helioseismic data sets by 0.03 to 0.08 microhertz. The differences arise from a combination of systematic errors, random errors, and possible changes in solar structure.  相似文献   
36.
The stable carbon isotope (delta13C) compositions of individual fatty acid components of remnant fats preserved in archaeological pottery vessels show that dairying was a component of archaeological economies. Characteristic delta13C values arise from biases in the biosynthetic origins of the C18:0 fatty acids in milk and adipose fat. Milk and adipose fat from animals raised on similar pastures and fodders have distinct isotopic signatures.  相似文献   
37.
Objective To investigate the efficacy of ivermectin in an intraruminal controlled-release capsule (CRC) against blowfly strike.
Design Pen and field trials with controls.
Animals Pen studies: Two breech strike trials involving 60 Romney and 60 Merino sheep. One body strike trial using 100 Merino sheep.
Field trials: Eight trials in New Zealand used 1000 Romney and Romney-cross sheep. Fifty Merino lambs in one trial in Australia.
Procedure Pen studies: Sheep were allocated to two equal groups. One was not treated, the other sheep received a CRC that delivered ivermectin at 20 μg/kg/day for 100 days. In the breech strike trials, each animal was given an oral laxative 2 days before exposure to adult Lucilia cuprina . In the body-strike trial, the sheep sheep were kept wet to increase susceptibility prior to the release of blowflies.
Field trials: Fifty or 200 sheep allocated to equal groups of nontreated or treated with the CRC and grazed at pasture exposed to natural blowfly challenge.
Results Pen studies: Breech strikes developed in 24 of 60 controls but in none of 60 CRC-treated sheep. There was a 35% reduction in the number of CRC-treated sheep struck on the body.
Field trials: The average number of breech strikes in CRC-treated sheep was reduced by 86% (P < 0.001). The number of body strikes in the treated groups was a reduced by 27% (P < 0.05).
Conclusion The ivermectin CRC is a useful aid in controlling breech strike, but provides only moderate reduction in the incidence of body strike.  相似文献   
38.
Objective To confirm the efficacy of ivermectin released from a controlled-release capsule administered to young sheep and to breeding ewes under field conditions. Design Randomised field trials. Procedure In each of ten field trials 25 weaned lambs were treated with ivermectin controlled-release capsules and 25 remained untreated. Eight similar field trials were conducted using adult ewes. Efficacy against infections of gastrointestinal nematodes was assessed by faecal egg counts and faecal larval culture. Body weights were recorded and faecal soiling of the breech wool (dags) was assessed. Results Nematode faecal egg counts in the two groups were not different (P = 0.13) before treatment in the weaner trials or before treatment in the ewe trials (P = 0.49), but thereafter eggs in the untreated sheep persisted, whereas counts in sheep given capsules were negligible (P ≤ 0.01). In the weaner trials, dag scores for the two groups were not different at the start of the trials (P = 0.18) but at the end, untreated sheep had significantly more dags (P = 0.04) than treated sheep. In the ewe trials, dag scores remained low in both groups. Weaners treated with the capsule gained 1.4 kg (95% CL: 0.7, 3.1) more weight over the 16 week trial period compared to untreated weaners (P = 0.01). Both groups of ewes lost weight as a result of parturition but the mean loss by week 16 was greater for untreated (3.7 kg) (95% CL: -5.1,-2.2) than for treated ewes (1.8 kg) (95% CL: -3.3, -0.4). The mean change in ewe body weight for the two groups was however not significant (P = 0.07). Differentiation of nematode larvae recovered from cultures of faeces from untreated animals indicated that the capsules were effective against the common parasites of sheep. Conclusion The capsule was efficacious against gastrointestinal nematodes judging from faecal egg counts. It has the potential to significantly reduce contamination of pasture with nematode eggs. Treated weaners had less dags for 16 weeks and gained more weight than untreated weaners.  相似文献   
39.
Stem cells have been isolated from ovaries, and their ability to differentiate into oocytes in vitro has been demonstrated for mice and human, but not for bovine species. The aims of this study were to isolate germline stem cells from bovine ovaries and to evaluate the effects of bone morphogenetic proteins (BMPs) 2 and 4, and follicular fluid on the differentiation of these stem cells into oocyte‐like structures. The ovarian stem cells were isolated and cultured in α‐MEM+ supplemented with BMP2, BMP4 or follicular fluid. On days 0 and 14, cells were evaluated for their morphological appearance, viability, expression of alkaline phosphatase and for markers of germ cell formation (VASA and DAZL) and oocyte development (GDF9, ZPA and SCP3) by qPCR. Levels of mRNA were analysed using ANOVA and Bonferroni test (p < .05). The results showed that at day 0, ovarian stem cells expressed specific markers of pluripotency (OCT4, SOX). In addition, these cells were positive for alkaline phosphatase, which is a marker commonly used to identify primordial germ cells (PGCs). After the period of differentiation, cells had morphological features that resemble PGCs and oocyte‐like cells (OLCs). An increase, ranging from five to 14 times, in the expression of VASA was observed in cells cultured in medium supplemented with BMPs and follicular fluid, while the increase in DAZL expression ranged from four to six times. In addition, OLCs had an increase in expression of mRNAs for GDF9, ZPA and SCP3 that ranged from two to eight times. In conclusion, OLCs can be differentiated in vitro from ovarian stem cells and BMPs and follicular fluid are effective in stimulating the expression of mRNAs for germ cell and oocyte markers.  相似文献   
40.
Among the factors that affect the efficiency of somatic cell nuclear transfer (SCNT) in pigs, the activation protocol is the most variable among the current SCNT procedures. The aim of this study is focused on defining an efficient activation treatment of porcine oocytes. In Experiment 1, we studied the effects of nine different oocyte activation procedures (including chemical‐ and electrical‐based treatments) on parthenogenetic embryo development. In Experiment 2, we studied the effect of the more efficient activation procedures on the gene expression profile of Oct4 and Igf2r in parthenogenetic blastocysts. In conclusion, ionomycin as a first calcium stimulus is not able to activate porcine oocytes efficiently in comparison with electric procedures. Electrical treatments with 6‐DMAP significantly increased the level of Oct4 expression, whereas the single and double pulse treatments alone maintained the same profile as the IVF group.  相似文献   
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