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Various methods are being employed to detect early pregnancy in domestic animals. This study aimed to predict early pregnancy in buffaloes via measuring the corpus luteum (CL) diameter, the luteal blood flow (LBF) area, the uterine blood flow (UBF) vascularization area, and progesterones in saliva and serum for non-pregnant (NPBs, N = 12) and pregnant (PBs, N = 12) buffaloes. The results revealed that the CL diameter and the luteal color blood flow blue and red (P = 0.0001) areas of the pregnant animals kept increasing from day 1 to day 35 of the gestation period, but it decreased in NPBs on day 21 after reaching a peak from ovulation to day 18. Interestingly, the UBF of the pregnant buffaloes (PBs) kept increasing (P = 0.0001) from ovulation to day 42. The difference of the CL diameter (P = 0.03) and the LBF color blue vascularization area (P = 0.002) between PBs and NPBs became clear from day 14 after ovulation, though the difference of UBF between PBs and NPBs became markedly obvious from day 7 after breeding. Both saliva (P = 0.001) and serum (P = 0.0001) progesterones of PBs continued increasing (P = 0.0001) from day 14 to day 35, but those of NPBs started decreasing (P = 0.0001) from day 14 and reached low values on day 21. Therefore, measuring saliva progesterone in addition to the high LBF (day 14) and UBF (day 7) of the pregnant buffaloes using a Doppler ultrasound could be applicable as noninvasive methods to detect early pregnancy and to improve reproductive management of buffaloes.  相似文献   
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Although color Doppler ultrasonography has been used to evaluate testicular blood flow in many species, very little has been done in goat. Eight male Shiba goats were exposed to a single intramuscular injection of either gonadotropin-releasing hormone (GnRH group; 1 µg/kg BW) or human chorionic gonadotropin (hCG group; 25 IU/kg BW). Plasma testosterone (T), estradiol (E2) and inhibin (INH) were measured just before (0 hr) and at different intervals post injection by radioimmunoassay. Testis volume (TV) and Doppler indices, such as resistive index (RI) and pulsatility index (PI) of the supratesticular artery, were measured by B-mode and color Doppler ultrasonography, respectively. The results indicated an increase in testicular blood flow in both groups, as RI and PI decreased significantly (P<0.05), but this increase was significant higher and earlier in hCG group (1 hr) than in the GnRH group (2 hr). A high correlation was found for RI and PI with both T (RI, r= −0.862; PI, r= −0.707) and INH in the GnRH group (RI, r=0.661; PI, r=0.701). However, a significant (P<0.05) correlation was found between E2 and both RI (r= −0.610) and PI (r= −0.763) in hCG group. In addition, TV significantly increased and was highly correlated with RI in both groups (GnRH, r= −0.718; hCG, r= −0.779). In conclusion, hCG and GnRH may improve testicular blood flow and TV in Shiba goats.  相似文献   
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Proteins in sporulated and unsporulated oocysts of Eimeria maxima were characterized, using monoclonal antibodies (MAB), ELISA, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and protein (western) immunoblotting techniques. Three MAB (EM1, EM2, and EM4) were produced against proteins of sporulated oocysts. The ELISA results indicated that EM1 was reactive with sporulated oocyst proteins, EM2 was reactive with sporulated and unsporulated oocyst proteins, and EM4 was reactive with unsporulated oocysts and proteins. Separation of proteins in E maxima sporulated and unsporulated oocysts by SDS-PAGE indicated that sporulated oocysts had proteins of approximately 200 kilodaltons (kD) and distinct protein bands at 21.5 and 45 kD. Using SDS-PAGE, unsporulated oocysts had less-distinct high molecular weight protein bands (greater than 200 kD), compared with sporulated oocysts, and a distinct protein band at 31 kD. Use of all 3 MAB yielded negative results in western blot analysis of fractions obtained by SDS-PAGE.  相似文献   
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Naturally high total dissolved solids and upstream agricultural runoff often mask the influence of urban land cover on stream chemistry and biology. We examined the influence of headwater urbanization on the water chemistry, microbiology, and fish communities of the Big Brushy Creek watershed, a 96 km2 drainage basin in the piedmont of South Carolina, USA. Concentrations of most major anions and cations (especially nitrate, sulfate, chloride, sodium, potassium, and calcium) were highest in the urban headwaters and decreased downstream. Generally, the highest concentrations of suspended coliform bacteria occurred in the urban headwaters. In contrast, stream habitat quality and the abundance, species richness, and species diversity of fishes did not differ significantly between urban and rural sites. Discharge of wastewater treatment plant effluent at one rural location caused an increase in concentrations of many solutes and possibly the abundance of benthic algae. We hypothesize that atmospheric dry deposition and domestic animal wastes are important sources of stream solutes and of coliform bacteria, respectively, in the urban headwaters. The lack of significant differences in fish abundance and diversity between urban and rural sites may indicate that urban development in the Big Brushy Creek watershed has not yet degraded habitat conditions greatly for stream fishes. Alternatively, agriculture or other land uses may have degraded stream habitat quality throughout the watershed prior to urbanization.  相似文献   
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Savanna vegetation is characterized by high and variable ground layer species richness regulated by functional group interactions with fire regimes and canopy cover. Frequent fire selects for C4 grasses and prairie forbs in canopy openings and C3 graminoid species and shade-adapted forbs and shrubs in canopy shade. Frequent fire also maximizes heterogeneity in partial canopy cover and species richness across the full canopy gradient. However, few studies have linked fire induced change in tree canopy cover with groundlayer vegetation dynamics in relation to this model. In 1986 and in 2007, we measured canopy cover and sampled groundlayer vegetation in 1 m2 plots along 53 transects at the Tefft Savanna, a fire managed 197 ha eastern sand savanna with strong canopy cover and elevation gradients. We analyzed temporal change in canopy cover and groundlayer vegetation, correlating percent change in canopy cover with change in ground layer functional groups. After 20 years of burning at 3 fires/decade, elevation accounted for 62% of the variation in an NMS ordination of groundlayer vegetation. However, canopy cover, which averaged 24-86% in 2007, had a significant secondary effect on the ordination. Five vegetation types classified by TWINSPAN varied significantly in elevation and canopy cover. Woody vegetation comprised 8 of the 12 species with greatest niche breadths, and tended to predominant in woodland or forest, where tree cover averaged 50% or more. Forbs had greater richness in savanna, which averaged less than 30% canopy cover. The C3 sedge Carex pensylvanica was the dominant graminoid species under woodland canopy cover, and was co-dominant with the C4 grasses Andropogon scoparius and Sorghastrum nutans under savanna canopy cover. As in other savannas, N-fixing species sorted across shade and canopy openings, and heterogeneity among transects was maximized at mid-canopy cover. Over time, canopy cover decreased up to 50%, creating more open savanna conditions at mid to high elevations. This decrease was associated with a 20-100 % increase in species richness and was significantly correlated with increasing richness and cover of C4 grasses and summer flowering prairie and woodland forbs. These results support a canopy cover model of fire-maintained savanna vegetation, with greater abundance of C4 grasses and prairie forb species associated with lower canopy cover, greater heterogeneity at mid-canopy cover, and species richness maximized across the light gradient. They also indicate that decreasing canopy cover caused by repeated burning increases species richness and abundance of C4 and prairie forb species.  相似文献   
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Cytoplasmic proteins from unsporulated and sporulated Eimeria maxima oocysts were analyzed by gel-filtration column chromatography. Unsporulated oocysts were characterized as having 3 major cytoplasmic proteins and sporulated oocysts as having 5 major cytoplasmic proteins. Molecular weights ranged from 5 x 10(3) to 1.4 x 10(6). Larger molecular weight proteins were detected in sporulated and unsporulated oocysts, but were associated more with sporocysts of sporulated oocysts.  相似文献   
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