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61.
Summary Three lentil (Lens culinaris Medic.) populations were advanced from the F2 to the F4 generation by singleseed-descent (SSD) and bulk-population (BP) breeding methods and used to compare the relative efficiency of the methods for maintaining genetic variation and selection opportunities.SSD maintained more genetic variation (% MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGak0dh9WrFfpC0xh9vqqj-hEeeu0xXdbba9frFj0-OqFf% ea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs0dXdbPYxe9vr0-vr% 0-vqpWqaaeaabaGaaiaacaqabeaadaqaaqaaaOqaaiqbeo8aZzaaja% Waa0baaSqaaiaadEgaaeaacaaIYaaaaaaa!3B04!\[\hat \sigma _g^2 \]) in 15 of 21 comparisons of characters that were made. Genetic variances were significantly higher with SSD for plant height, days to maturity and yield in population 1; height of lowest pod in population 2; and days to blooming, height of lowest pod, plant type, and yield in population 3. SSD-derived populations had 10, 9, and 13% more erect lines in the three populations, respectively, when compared to the same populations advanced by BP. The BP method maintained 14, 2, and 4% more taller types in the three populations, respectively, and 16 and 33% more segregants that carried their pods higher from the ground. This indicated a reduced frequency of short plants with low flowers as a result of natural selection operating within BP against less competitive short types. The SSD method is an efficient cost-saving method of advancing lentil populations and is recommended for lentil breeding.Scientific Paper No. 5478.  相似文献   
62.
Objective To document an ovine disease attributed to the consumption of Lythrum hyssopifolia (lesser loosestrife). Procedures Historical and histological review of field and experimental cases. Results 1–20% mortality occurred in sheep flocks grazing paddocks where L. hyssopifolia was the predominant green vegetation. Well‐documented disease outbreaks occurred in summer on nine farms across Victoria between 1974 and 2002. Liver damage occurred in all nine outbreaks, with kidney damage in at least eight. Hepatocyte necrosis was usually zonal to midzonal (zone 2) in the liver samples from four farms and periacinar (zone 3) in those from three farms, but some livers showed only single‐cell necrosis. Multinucleate hepatocytes near necrotic areas were a feature in six cases. Proximal tubular epithelium appeared to be the primary renal target and brown granules were often present in renal tubules. Biochemical and histological evidence of liver and kidney damage was obtained from two sheep experimentally pen‐fed harvested L. hyssopifolia. Conclusion Chemicals in L. hyssopifolia are toxic to ovine hepatocytes and renal tubular epithelial cells.  相似文献   
63.
SUMMARY: The IgG concentration of plasma from 13 mares was measured by radial immunodiffusion when fresh and after storage at -4°C and thawing by 3 methods. There was no significant (P > 0.05) reduction in the IgG concentration when plasma was thawed over 6 hours at 22°C (1352.9 ± 101.6 mg/dL) (mean ± SEM) compared with the fresh sample (1369.5 ± 88.1 mg/dL). In contrast, there was a significant (P < 0.05) reduction in the IgG concentration of plasma that was rapidly thawed at 57°C over 50 minutes (1142.9 ±66.2 mg/dL), or placed in a microwave oven for 20 to 25 minutes (1093.4 ± 74.4 mg/dL). When plasma is administered to hypo-gammaglobulinaemic newborn foals, a larger volume is required when thawing is rapid than when thawing is slow or when fresh plasma is administered.  相似文献   
64.
The effects of bovine leukemia virus (BLV) on the immune response have been extensively investigated; however, its effects on mammary gland immunity are only speculative. Although BLV has a tropism for B cells, it can affect both adaptive and innate immunities because these systems share many effector mechanisms. This scenario is the basis of this investigation of the effects of BLV on mammary gland immunity, which is largely dependent upon neutrophilic functions. Thus, the present study sought to examine neutrophilic functions and the lymphocyte profile in the milk of naturally BLV-infected cows. The viability of the milk neutrophils and the percentage of milk neutrophils that produced reactive oxygen species (ROS) or phagocytosed Staphylococcus aureus were similar between BLV-infected and BLV-uninfected dairy cows. Furthermore, the expression of CD62L and CD11b by the milk neutrophils and the percentage of milk neutrophils (CH138+ cells) that were obtained from the udder quarters of the BLV-infected cows were not altered. Conversely, the median fluorescence intensity (MFI) representing intracellular ROS production and the phagocytosis of S. aureus, the expression of CD44 by the milk neutrophils and the percentage of apoptotic B cells were lower in the milk cells from BLV-infected dairy cows, particularly those from animals with persistent lymphocytosis (PL). The lymphocyte subsets were not different among the groups, with the exception of the percentage of CD5/CD11b B cells, which was higher in the milk cells from BLV-infected cows, particularly those with PL. Thus, the present study provides novel insight into the implications of BLV infection for mammary gland immunity.  相似文献   
65.
Stewing of rice grains by steam after boiling in excess water can be used for cooking rice perfectly. The effects of this procedure in cooking of three varieties of Iranian rice (Sang Tarom, Domsiyah and Fajr) on textural and morphological properties of cooked rice grains were investigated. The results showed that this step in rice cooking reduced the hardness and increased the adhesiveness of rice grains significantly. By the use of the scanning electron microscopy, it was shown that the outer surface of cooked rice stewed by steam had less porosity and closer pores due to the modification during cooking, and better gelatinization and more expansion of starch granules compared to non-stewed samples. The use of this procedure in rice cooking to provide a fully cooked and gelatinized, softer and stickier final product is recommended.  相似文献   
66.
67.
Google Earth® provides free access to satellite images and has been used in several areas that require cartographic information. The present study assessed the inconsistencies between geo-referencing of livestock premises by GPS and the acquisition of geographic coordinates by remote sensing (RS) images provided by Google Earth® in the Brazilian states of Bahia, Distrito Federal, Minas Gerais and Parana. The overall mean and standard deviation of the distances in the study were 30.98 ± 19.89 m. The mean distance differences between the two techniques were, for these states, 37.20 ± 19.75 m, 28.38 ± 17.38 m, 31.61 ± 15.72 m, 28.43 ± 24.30 m, respectively. Despite the fact that there is variation between the geo-referencing points using GPS and RS, geographical localization of health inspections should be useful as long as the errors between the results of the two methodologies are considered.  相似文献   
68.
Many farmlands are periodically flooded or ponded by excessive precipitation resulting in changes to soil chemical and biochemical properties. In this study, one set (eight treatments with four replications) of field-moist surface soils (0–15 cm) and their air-dried counterparts obtained from a long-term liming experiment were incubated at 30 °C under waterlogged conditions for 10 days, and the amounts of net NH4 +-N released (soluble and exchangeable) were determined after extraction with 4 M KCl. Another set of three surface soils were used to evaluate the effect of six heavy metals on the NH4 +-N release under waterlogged conditions. Results showed that increasing the liming rate from 0 to 17,930 kg ha?1 effective calcium carbonate equivalent increased the average soil pH from 4.98 to 7.06, averages of the amounts of NH4 +-N released ranged from 1.6 to 5.2 mg N kg?1 field-moist soil, and the corresponding amounts released in air-dried soils ranged from 18.9 to 32.9 mg N kg?1 soil. This increase of the amount NH4 +-N released in air-dried soil samples is presumably due to a slaking effect. At 5 mmol kg?1 soil, all six heavy metals inhibited the NH4 +-N released. The relative effectiveness of the heavy metals in inhibition of the NH4 +-N released varied among the three soils. Lead(II) was the most effective inhibitor of NH 4 +-N release in Clarion and Harps soils and Cd(II) in Harps soil. Cobalt(II), Cu(II), and Cd(II) were the least effective inhibitors of NH4 +-N release in Clarion, Harps, and Okoboji soils, respectively.  相似文献   
69.
The aim of this study was to investigate the effect of applying a progesterone‐based oestrous synchronization protocol at 51–57 days postpartum in high‐producing dairy cows. The data analysed were derived from 1345 lactating cows. Cows between 51 and 57 days postpartum were assigned to the groups: control, PRID (receiving a progesterone‐releasing intravaginal device for 9 days, and prostaglandin F 24 h before PRID removal) or GnRH–PRID (the same as the PRID group plus GnRH at PRID insertion). Oestrus was detected by using pedometers and confirmed by examination of the genital tract at AI. Oestrous and conception rates before days 71–77 postpartum, pregnancy loss in early pregnant cows or the cumulative conception rate registered on day 120 postpartum were considered as the dependent variables in four consecutive logistic regression analyses. Based on the odds ratios, the oestrous rate increased by a factor of 1.73 in cows showing oestrus before treatment for each unit increase in the number of previous oestruses; decreased by a factor of 0.44 in the control group with respect to the treatment groups; and by a factor of 0.61 in cows without luteal structures at treatment with respect to cows with corpora lutea. The conception rates of cows inseminated before days 71–77 postpartum remained similar across the groups, whereas the likelihood of pregnancy loss for cows becoming pregnant during this period was 0.11 times lower in the PRID group than in the control. Based on the odds ratio, the likelihood of a higher cumulative conception rate on day 120 postpartum: increased in cows showing oestrus before treatment by a factor of 1.41 for each unit increase in the number of previous oestruses, was reduced 0.56‐fold in control cows compared with treated cows, and was also reduced by a factor of 0.98 for each kilogram of milk production increase recorded at treatment. In conclusion, although oestrous synchronization programmes performed in this study did not improve fertility, cows treated with progesterone could be inseminated earlier than untreated cows, such that the treatments increased the cumulative pregnancy rates determined on day 120 postpartum. In addition, fewer pregnancy losses were observed in early pregnant cows in the PRID group than the GnRH–PRID group.  相似文献   
70.
The objective of this study was to evaluate different concentrations of growth hormone (GH) on the development of bovine preantral follicles cultured included in the ovarian tissue (in situ) on the rates of morphologically normal, viable, primordial and developing follicles, as well as the oocyte and follicle diameter and ultrastructural analysis. Ovarian fragments collected from cows with no cross‐breeds defined were cultured in situ for 1 and 7 days in minimal essential medium (α‐MEM+) supplemented with different concentrations of recombinant human GH (0, 10, 25, 50 ng/ml). The ovarian fragments non‐cultured (control) and cultured were processed for classic histology, mechanical isolation and electron transmission microscopy (MET). The parameters underwent anova (Tukey′s and Dunnett′s tests) and chi‐square test (χ2). After 7 days of culture, the treatment with 50 ng/ml GH showed no differences with fresh control (p > 0.05) and had greater effectiveness than in the 0, 10 and 25 ng/ml GH concentrations of the morphologically normal follicles. Regarding the primordial follicles, a reduction was observed in the 50 ng/ml GH concentration concomitant with the significant increase in developing follicles, differing from both the fresh control and the other GH concentrations tested. In addition, 50 ng/ml GH showed a larger follicle and oocyte diameter when compared to the other treatments cultured. Similar structures were ultrastructurally observed in the control group, 50 ng/ml GH. Follicles cultured in 10 ng/ml GH showed nuclear invagination, vacuoles and lesioned basal membrane. Hence, it is concluded that 50 ng/ml GH is the most effective concentration for the development of preantral follicles cultured in situ.  相似文献   
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