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871.
Soil Salinization Map of Russia on a scale of 1: 2500000 (the paper version) has been used for compiling an electronic map of the Ural Federal Region and an attribute database containing twelve characteristics of soil salinization. The areas of saline soils have been quantified for the entire region and its administrative districts. The total area of saline soils in the 0- to 200-cm layer averages up to 6.85 million ha or 5.53% of the plains in the region. The area of soilssaline in the 0- to 100-cm layer averages up to 4.91 million ha, including 4.13 million ha of weakly solonchakous soils (84%) and 0.78 million ha of solonchakous ones (16%). More than half of them (58.3%) are assigned to the moderately and strongly saline soils. The soils saline in the 0- to 100-cm layer are characterized by the neutral salinization type (45%) or the types of soda salinization and neutral salinization with soda (55%). The areas of the region with saline soils are dominated by solonetzic microassociations. The average area of the solonetzes is about 3 million ha. The area of solonchaks is about 0.09 million ha. The area of saline soils is the greatest in Kurgan oblast and the lowest in Sverdlovsk oblast and the Yamal-Nenets autonomous okrug. The formation of saline soils in the Ural Federal Region is related to the climatic conditions of the steppe zone with insufficient moistening and lithologicgeomorphologic conditions (saline Paleogene-Neogene deposits and poor drainage of the area).  相似文献   
872.
    
Bovine tactile hairs in skin samples from the lateral side of the upper lip were examined using scanning electron and light microscopy. The root of these hairs has a variable length and is surrounded by a large sinus located between the internal and the external dermal sheath. With a prominent thickness, the external dermal sheath forms the external wall of the tactile hair and contains many nerves some of which extend into trabeculae. Trabeculae projecting from the internal dermal sheath and attaching to the external dermal sheath with two or more branches are present in the entire sinus. The trabeculae are interconnected by connective tissue sheets that support the integrity of the trabecular organization. The sinus surfaces as well as trabeculae are lined by endothelia. As a result, the bovine tactile hair is truly a cavernous type of tactile hair with a well organized microscopic anatomy. Thus, the bovine tactile hair most likely plays an important role in relatively immobile and insensitive bovine lips.  相似文献   
873.
1.?The aim of the present study was to evaluate the yield and tissue composition of carcases from White Ko?uda® ganders (males) and geese (females), and to determine the relationships between body measurements and carcase tissue composition.

2.?The experiment was carried out on 200 geese (100 males and 100 females) reared to 14 weeks of age and then fed with oats for the next 3 weeks. Live body weight and body dimensions, slaughter yield, weight and percentage of muscles and skin with fat in carcase were measured and correlation coefficients were calculated between body measurements and slaughter values and carcase tissue composition.

3.?White Ko?uda® geese reared to 17 weeks of age were characterised by high body weight (6705 g) and good muscle yield (29·9%). Males had greater body weight, musculature and fatness than females. Sternum length and breast circumference, width and depth were good indicators of carcase muscle weight in 17-week-old geese.

4.?Negative coefficients of correlation between sternum length and weight of skin with subcutaneous fat indicate that increased selection pressure in pedigree flocks of geese on sternum length should be paralleled by reduced carcase fatness in these birds.  相似文献   

874.
    
Data from 1,909 purebred, F1, backcross and F2 and F3 inter se combinations of Angus and Hereford were used to estimate average individual, maternal and grandmaternal genetic effects, individual and maternal heterosis, dominance and epistatic genetic effects. Models for evaluating heterosis and epistatic or recombination effects were discussed. Average individual effects indicate that Angus, compared with Hereford, had calves that were born earlier, had lighter birth weights, lower pre- and postweaning gains and lower pregnancy rates. Angus also produced lighter weight carcasses with more fat cover and marbling. Maternal effects of Angus were in the direction of reduced birth weight, greater calving ease, higher preweaning but lower postweaning growth rate and increased fatness when contrasted with Hereford. There was a tendency for opposite direction of maternal and grandmaternal effects for traits influenced by preweaning maternal environment. When additive X additive effects were ignored, total heterosis was significant for earlier day born, heavier birth weight, preweaning and postweaning gain, and heavier and fatter carcasses. Heterosis retained in F3 inter se vs F1 generation crosses indicated that net epistatic effects were relatively negligible for date of calving, birth weight, weaning gain and fat cover. There was a greater reduction of heterosis effects than expected from dominance alone for survival, pregnancy and marbling score. Loss of heterosis in F3 was less than expected for postweaning gain, carcass weight and rib eye area. Except for survival, pregnancy and marbling, these deviations from dominance expectations, or lack of them, are favorable for F3 composite populations.  相似文献   
875.
    
Bread-making quality indices (dough strength and dough mixing stability) in relation to flour protein content, glutenin/gliadin ratio, and high-molecular-weight (HMW) subunits of glutenin have been investigated in Triticum aestivum progenies during a three year agronomic trial. Dough strength (W) proved to be a fairly stable characteristic, slightly but positively correlated with flour protein content. High could be associated with a high glutenin/gliadin ratio as well as with the presence of specific HMW. subunits of glutenin, while high protein content tended to favour a balanced dough tenacity-extensibility ratio (P/L = 0.4—0.6). Satisfactory values of dough-mixing stability were frequently observed in association with good expression of W showing that the two quality traits may coexist without much difficulty in the same genotype. From the plant breeding standpoint the data suggest feasible to obtain high dough strength by concentrating in a genotype the HMW subunits of glutenin known to have a beneficial effect on W. However, very high W may present unfavourable P/L ratios. This possibility is enhanced when the flour has a low protein content which often occurs in high yielding genotypes.  相似文献   
876.
Two 4 x 4 Latin square design experiments were carried out. In experiment 1, four mature Anglo-Nubian x Fiji local goats, pre-experimental body weight 25.0 +/- 0.6 kg, 22-24 months old, were used to study the effect of supplementation of a basal diet of maize stover with Erythrina variegata (EV), Gliricidia sepium (GS) and Leucaena leucocephala (LL) on dry matter intake (DMI) and nutrient digestibility. Maize stover treated with urea was used as a control diet. E. variegata was higher in crude protein content than LL or GS. The DMI of the urea treated stover diet was significantly lower (p < 0.05) than that of the diets of untreated stover supplemented with forage legumes. The DMI was significantly lower (p < 0.05) in the GS diet than in the EV or LL diets. Significant (p < 0.05) differences existed between the urea-treated stover and the diets of stover supplemented with forage legumes in the digestibility of dry matter (DM), crude protein (CP), neutral detergent fibre (NDF), organic matter (OM) and energy. In experiment 2, four mature goats, pre-experimental body weight 27.0 +/- 0.3 kg, 24-28 months old, were used to measure their response when the urea-treated maize stover and the maize stover and forage legume diets were sprayed with molasses. The intake of the urea-treated stover diet sprayed with molasses was significantly lower (p < 0.05) that that of the maize stover/forage legume diets sprayed with molasses. The DMI of the diets improved with the addition of molasses. The DMI among the goats offered the maize stover/forage legume diets + molasses did not differ significantly. (p > 0.05). Statistically significant (p < 0.05) differences were obtained in this second study between the urea-treated stover and the stover supplemented with forage legumes in the digestibility of DM, CP, NDF, OM and energy. The stover supplemented with forage legumes had a higher (p < 0.05) nutrient digestibility. The present studies demonstrated that the use of forage legumes as protein supplements improved the feed quality of maize stover in the diets of mature goats. It is suggested that molasses should be sprayed on fresh leaves of Gliricicia sepium and other forage legumes that are initially rejected, in order to improve acceptance and DMI when fed to ruminant animals in confinement or in a cut-and-carry system of production.  相似文献   
877.
878.
    
Twenty stifles (10 dogs) were studied for a period of 1 year after various lesions of the cranial cruciate ligament and medial meniscus were produced surgicaoy. Through serial arthroscopic evaluations, degenerative processes In stifles with a \"torn\" cranial cruciate ligament were documented. Intra-articular changes were minimal after partial meniscectomy and were severe after total meniscectomy. Multiple arthroscopies caused no demonstrable changes.  相似文献   
879.
880.
This study was conducted to determine whether an antimicrobially induced (ASP-250) increase in serum IGF-I was the result of differences in feed intake. Serum IGF-I concentrations were measured in crossbred pigs that were fed a control diet or a diet supplemented with ASP-250 either for ad libitum consumption or limited to 85% of the control pigs' consumption. The pigs that consumed either diet ad libitum, control or ASP-250, consumed similar quantities of feed. The ASP-250 ad libitum-intake pigs had serum IGF-I concentrations that were greater (P<.01) than those of their ad libitum-intake control littermates. Similarly, the ASP-250 limit-fed pigs had serum IGF-I concentrations that were greater (P<.01) than those of the controls. Although the serum IGF-I concentrations of pigs fed the ASP-250-supplemented diet for ad libitum intake were greater than the serum IGF-I concentrations of the pigs limit-fed the ASP-250-supplemented diet, the differences were not significant (P<.08). The ASP-250-fed pigs had higher serum IGF binding protein (BP)-3 concentrations than did their control littermates (P<.003). A time course of antimicrobially induced alterations in serum IGF-I concentrations revealed that the effect of increased serum IGF-I levels in ASP-250-supplemented pigs (P<.02) was observed within 4 d and was maintained throughout the 4-wk study. These findings show that feed intake is not responsible for the increase in serum IGF-I observed with ASP-250 supplementation. Additionally, the antimicrobially induced increase in serum IGF-I concentrations occurs within a few days after initiation of the treatment.  相似文献   
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