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81.
Ninety sexually mature Cherax quadricarinatus females were exposed to various combinations of photoperiod and temperature for 2 months during the summer. Females were randomly assigned to either “winter” “semi-winter” or “summer” simulation treatments. In the “winter” treatment, crayfish were exposed to a simulated winter photoperiod (gradual decrease from 14L:10D to 10L:14D, 4 weeks at short day length followed by gradual increase to 14L:10D) and temperature (gradual decrease from 27 to 15 °C, held for 4 weeks, and then gradual increase to 27 °C). In the “semi-winter” treatment, crayfish were exposed to a simulated winter photoperiod and a summer temperature (27–29 °C). In the “summer” treatment, the crayfish were exposed to summer water temperatures and a photoperiod of 14L:10D. Following the 2 months of conditioning, the females were stocked for 7 months in small groups with males under environmental conditions similar to those of the “summer” treatment. All females were individually tagged and molting and spawning events were monitored. Females exposed to “semi-winter” conditioning in the summer, demonstrated a threefold increase in the rate of first spawning during the winter (December–February) compared with the other females. Crayfish breeders can easily implement these findings since shifting the breeding season into the winter only requires shortening of the photoperiod in the summer. The stocking of ponds in the spring with large nursed juveniles that hatched from eggs spawned in the winter, would allow the attainment of market size at the end of the limited growout season in temperate zones.  相似文献   
82.
A 10-month-old Arabian foal was evaluated for a suspected immunoglobulin (Ig) M deficiency. Decreased to nondetectable concentrations of IgM, IgA, and IgG (T), and a normal concentration of IgG, were present. Results of in vitro testing of the blood lymphocyte blastogenesis showed a weak response to the B-cell mitogen, lipopolysaccharide (LPS), but normal responses to T-cell mitogens. Results of postmortem examination showed synovitis of the left tibiotarsal and both scapulohumeral joints. Atrophy and edema of the lymph nodes and lymphocyte depletion in the thymus and spleen were seen. A subacute inflammatory infiltrate was observed in the kidney, synovium, liver, and brain. Etiologic agents were not identified. This case represents a previously unreported form of immunodeficiency disease in the horse.  相似文献   
83.
Tropical Animal Health and Production - Based on current knowledge, C16 and C18 fatty acids (FA) are considered the most functional FA in hepatic metabolism. Although these FAs have been...  相似文献   
84.
The present study aims to comparatively evaluate the effects of different doses of intravenous xylazine and medetomidine on sedation and antinociception scores, and physiological and laboratory parameters in dromedary calves. Thirty clinically healthy male dromedary calves 15 ± 2 weeks old and weighing 95 ± 5.5 kg were studied. Two groups received xylazine at low (0.2 mg/kg) and high (0.4 mg/kg) doses. Two groups received medetomidine at low (10 µg/kg) and high (20 µg/kg) doses. One group received normal saline. Sedation signs were scored using a 3‐point scale. Analgesic effect was analyzed using pinpricks. Data were analyzed by one‐way ANOVA and Mann–Whitney U‐tests. Sedation and antinociception scores of the animals 1 hr after receiving the higher dose of xylazine and medetomidine were significantly higher than that of other groups. Compared with other studied groups, the animals receiving the higher dose of xylazine showed significantly higher potassium and creatinine serum levels after 24 hr. Doses as high as 0.4 mg/kg for xylazine and 20 µg/kg for medetomidine can be considered safe and useful for procedures associated with mild pain in dromedary calves.  相似文献   
85.
The reproductive system in female birds arises as bilateral asymmetrical anlagen, excluding the birds of prey. Earlier, histological and messenger RNA (mRNA) expression profile studies of several genes related to gonadal sex differentiation in chicken embryos tried to elucidate the query of this asymmetry in a scattered manner. To understand the matter precisely, we have focused on mRNA expression of a cohort of genes (FSHR, CYP19A1, caspase 3, caspase 8) in second half of the embryonic days (E10–E18). The established role of leptin in development of the embryo and its expression in the embryonic ovary also drove us to check leptin receptor (LEPR) expression in the ovary. Increased expression of FSHR and CYP19A1 in the left ovary compared with that in the right ovary was identified (< 0.05), promoting preferential left ovarian development and functionality. Significant high expression (< 0.05) of the apoptotic genes in the right ovary were also involved here. Leptin probably has no direct influence on ovarian asymmetry as no significant variation in gonadal mRNA expression of LEPR was observed within the same experimental days. We propose that asymmetric expression of this cohort of genes (FSHR, CYP19A1, caspase 3, caspase 8) leads to the development of dimorphic gonads during embryogenesis.  相似文献   
86.
87.
Development plans are mainly responsible for population changes and the conversion of forest and rangelands into agricultural lands and human settlements. Qualitative and quantitative analysis of population and land use changes are necessary to assess the impacts of change on hydrological processes. However, such important issues have been less considered worldwide particularly in developing countries. Therefore, we selected the Shazand Watershed (1740 km2) because of rapid industrialization to track the effects of land use and population changes on streamflow and sediment yield. The data were collected from statistical yearbooks and satellite imageries from 1973 to 2008. All available measurements on discharge and suspended sediment concentration at the Pole doab hydrological station were also collected. The study was conducted for the whole period, as well as the pre‐1991 and post‐1991 as a basis for the economic development growth in the region. We found that the land use and population changes have occurred in the Shazand Watershed, especially in the vicinity of industrial zones. The results showed that the cities, industrial zones, roads, and bare lands quickly increased from 58 · 8 to 134 · 3 km2 during post‐1991. The flow durations, sediment rating curves and trend analyses indicated distinct variations in the relationship between streamflow and sediment and also caused changes within different periods. Based on the results, the mean annual flow and sediment yield in post industrialization (1991–2008) were respectively 0 · 84 and 1 · 19 times of those for pre‐industrialization period and the annual sediment yield increased from 25,000 to 29,850 Mg. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
88.
BACKGROUND: Knowing that adenoviral vectors could initiate innate immunity, the ability of E1-deleted recombinant adenovirus (Ad-E1Delta) in induction of B7.1 and IL-2 molecules was studied. METHODS: The expression of green fluorescent protein in C1498 cells following transfection of these cells with adenovirus green fluorescent protein vector confirmed the ability of adenovirus vectors in infecting the cells and inducing the expression of the gene of interest. The expression of B7.1 molecule on the surface of the cells was assayed upon infection with Ad-E1Delta vector. Adenovirus-IL-2/B7.1 vector capable of inducing IL-2 and B7.1 expression in the cells was used as the positive control vector. RESULTS: According to the FACS results, about 4.17% of normal cells expressed B7.1 on their surface, while this level was increased in Ad-E1Delta transduced cells up to 14.43%. These results demonstrate that Ad-E1Delta vector considerably (about 3 folds) increases the expression of B7.1 on the cells. No detectable IL-2 was secreted into the medium of non-transduced and Ad-E1Delta transduced cells. CONCLUSION: Data indicate that the infection of C1498 cells with recombinant adenoviruses stimulates expression of B7.1 on the cell surface rather than secretion of IL-2 into the medium.  相似文献   
89.
Mean field theories of ion distributions, such as the Gouy-Chapman theory that describes the distribution near a charged planar surface, ignore the molecular-scale structure in the liquid solution. The predictions of the Gouy-Chapman theory vary substantially from our x-ray reflectivity measurements of the interface between two electrolyte solutions. Molecular dynamics simulations, which include the liquid structure, were used to calculate the potential of mean force on a single ion. We used this potential of mean force in a generalized Poisson-Boltzmann equation to predict the full ion distributions. These distributions agree with our measurements without any adjustable parameters.  相似文献   
90.
Much effort has been invested in identifying molecular markers in wheat (Triticum aestivum L.) linked to quantitative trait loci (QTL) that confer resistance to Fusarium head blight (FHB) caused by Fusarium graminearum Schwabe [teleomorph Gibberella zeae (Schwein) Petch]. Even after several generations of crossing and selection by many wheat breeding programs, resistance of the Chinese spring wheat cultivar ‘Sumai 3’ (PI 481542) remains among the most effective. It therefore seems that undocumented resistance QTL present in Sumai 3 were not detected in various mapping studies. Using an extremely susceptible Tibetan landrace (‘Y1193-6’; unknown pedigree) in the creation of a mapping population with Sumai 3, the objective of this research was to identify undocumented resistance QTL in Sumai 3. This was accomplished through collecting disease index (DI) and Fusarium damaged kernel (FDK) phenotypic values along with 305 Diversity Array Technology (DArT) and 52 Simple Sequence Repeat (SSR) marker genotypes on 160 F2:6 recombinant inbred lines (RILs). Disease response evaluations were based on four (two greenhouse and two field) experiments where spray inoculation methods were used. Three QTL were identified on chromosome arms 3BS, 6BL and 2DS explaining 26.1, 10.7 and 18.9% of the phenotypic variation for DI, respectively. The same QTL were also significantly associated with reduced FDK scores and explained 28.0, 11.0 and 23.0% of phenotypic variation. Lines within the mapping population were placed in eight categories with respect to their various QTL combinations. Lines with no QTL were the most susceptible, whereas those with the Sumai 3-derived 3BS and 6BL QTL combined with the 2DS QTL from Y1193-6 were the most resistant. Though the 3BS and 6BL QTL are well-documented, the 2DS resistance QTL, which was contributed by the susceptible parent, confers increased susceptibility when derived from Sumai 3. In this study no new FHB QTL from Sumai 3 was discovered, but results suggest that Sumai 3 contains a QTL for susceptibility on chromosome arm 2DS. Selection against this QTL may potentially increase resistance levels among Sumai 3-derived populations.  相似文献   
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