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1.
The water buffalo (Bubalusbubalus) is an important economic specie in southern provinces that was acclaimed as the most potential and valuable development on the livestock by FAO. The new molecular biology technology will bring the new challenge and opportunity for buffalo researches in recent years. Many major breakthroughs have been made in the research area on the molecular biology technology of the water buffalo, which should reveal its great superiority and development potential on the buffalo genetics and breeding. Consequently, the molecular biology technology applied to the buffalo genetics and breeding and its prospect will be discussed, mainly including the molecular marker, gene chip, transgenic technology and high-throughput sequencing technology, etc. It will lay a foundation for further research on the molecular biology technology of the water buffalo and play an important role in promoting the rapidly development of the buffalo industry.  相似文献   

2.
1. The quantities of water gained and lost, and hence the total water balance, were determined in normal and colostomised White Leghorn laying hens at ambient temperatures of 5, 20 and 35 °G.

2. In both groups the water intake and water loss at all temperatures were well balanced.

3. Water to food ratios and water content of excreta of normal hens increased with increasing temperature.

4. The wetter excreta at 35 °C are caused by an increased urine production and not by an increased water passage through the alimentary tract.  相似文献   


3.
Managers reduce piñon (Pinus spp.) and juniper (Juniperus spp.) trees that are encroaching on sagebrush (Artemisia spp.) communities to lower fuel loads and increase cover of desirable understory species. All plant species in these communities depend on soil water held at &spigt; -1.5 MPa matric potential in the upper 0.3 m of soil for nutrient diffusion to roots and major growth in spring (resource growth pool). We measured soil water matric potentials and temperatures using gypsum blocks and thermocouples buried at 0.01–0.3 m on tree, shrub, and interspace microsites to characterize the seasonal soil climate of 13 tree-encroached sites across the Great Basin. We also tested the effects of initial tree infilling phase and tree control treatments of prescribed fire, tree cutting, and tree shredding on time of available water and soil temperature of the resource growth pool on nine sites. Both prescribed fire and mechanical tree reduction similarly increased the time that soil water was available (matric potential &spigt; -1.5 MPa) in spring, but this increase was greatest (up to 26 d) when treatments were applied at high tree dominance. As plant cover increased with time since treatment, the additional time of available water decreased. However, even in the fourth year after treatment, available water was 8.6 d and 18 d longer on treatments applied at mid and high tree dominance compared to untreated plots, indicating ongoing water availability to support continued increases in residual plants or annual invaders in the future. To increase resistance to invasive annual grasses managers should either treat at lower or mid tree dominance when there is still high cover of desirable residual vegetation or seed desirable species to use increased resources from tree reduction. This strategy is especially critical on warmer sites, which have high climate suitability to invasive species such as cheatgrass (Bromus tectorum L.)  相似文献   

4.
In order to ascertain water consumption characteristics of typical compound green space (CGP) which composed of turf and white elm in Urumqi city. Field irrigation experiment with fixed irrigation frequency and changed irrigation quota was carried out in Hongshan Park Urumqi. The results showed that average daily water consumption (ADWC) of lawn and white elm in CGP increased with the increase of irrigation quota,and showed the same trend of single peak curve (increased first and then decreased with the development of growth period). Cumulative water consumption of CGP in each treatment varied between 668.5~996.4 mm,which increased with the increase of irrigation quota. The ratio of water consumption between lawn and elm in CGP varied from 1:1 to 1:1.2,which increased first and then decreased with the increase of irrigation quota. The crop coefficient of CGP in each treatment during May to September varied between 0.72 and 1.52,and the average value of crop coefficient in each treatment during main growth period increased with the increase of irrigation quota. Considering the water consumption and growth of CGP,in the dry year with 75% rainfall frequency,the suitable irrigation quota of similar CGP with similar maintenance level is 36 mm,and the irrigation period is 5~7 days in Urumqi city. © 2019 Journal of Refrigeration. All rights reserved.  相似文献   

5.
This paper reports results of a study conducted to investigate the concentrations of seven mineral elements in yak blood, forage and water resources around the Qinghai Lake in Qinghai Province in different seasons. Meanwhile, the nutritional compositions of the forage were also surveyed. The results suggest that the mineral elements and the forage nutrients change in a seasonal pattern. In yak blood,the sodium(Na)concentration varies from 0.291 to 0.034 mg/mL,and this is lower than the normal value. In the forage,the ratio calcium(Ca)to phosphorus(P)is 4.06~7.47:1 and potassium(K)to Na 30~27:1. These results indicate that the nutrition of the yak in the area is deficient in Na but high in K. For the withered forage sampled in February,the protein content is only 31.14% of the total protein in the forage growing at puerile stage in June. The severe loss of protein by 68. 9% and decrease of effective nutrients in the wintered forage are considered to be the reasons resulting in the poor condition of yak in winter and spring seasons.  相似文献   

6.
To explore the law of water consumption in the underlying surface of a typical alpine desert on the Qinghai-Tibet Plateau, we analyzed the characteristics of ET change and water consumption on different time scales based on the raw eddy-covariance data and meteorological data measured in April to August 2019 from the observation tower on Tuotuohe weather station. The maximum hourly average ET appears at 2-3 p. m, reaching 0.46 mm·h-1; The maximum value of daily ET was 8.58 mm·d-1 on July 7, and the minimum value was 0.30 mm·d-1 on April 2; The ET increased first and then decreased during the growing season, the monthly ETmax was 120.68 mm in July and the ETmin was 64.80 mm in April; The total ET in 2019 growth season was 581.15 mm and the daily average was 4.01 mm. The total precipitation of the whole growing season was 235.70 mm, according to the difference between ET and precipitation(Pr) from April to August, water vapor exchange during the plant growth season was mainly characterized by water consumption on the land surface in 2019. © 2019 Authors. All rights reserved.  相似文献   

7.
In order to explore the synergistic growth of Kentucky bluegrass and herbaceous ornamentals in the garden plants configuration, the water extractions from leaves and rhizomes of Kentucky bluegrass (Poa pratensis) was used to examine the allelopathic effects on seed germination of Orychophragmus violaceus Zinnia elegans Tagetes patula using petridishs with filter papers. Results showed that the water extractions of the leaves and rhizomes of Kentucky bluegrass inhibited seed germination of Orychophragmus violaceus, Zinnia elegans, and Tagetes patula by 33% and 48%, 27% and 39 %, and 24% and 48%, respectively. And the rhizome extraction appeared to be more effective than leaf extraction in terms of inhibiting the seed germination, and the growth of radicle and coleoptile. Three ornamentals also showed different sensitivity to the extractions of Kentucky bluegrass, and Orychophragmus was the most sensitive to the extractions. This study showed that Orychophragmus should not be planted with Kentucky bluegrass to avoid alleloathic effect on growth by Kentucky bluegrass. © 2019 China Agricultural University. All rights reserved.  相似文献   

8.
This experiment was aimed to explore the effect of different ratios of food to water of dry powder feed on growth performance,nutrient digestibility and nitrogen metabolism of growing Wusuli raccoon dogs.Thirty 11-week-old healthy Wusuli raccoon dogs with average body weight of (3.47±0.20) kg were randomly assigned into 3 groups.The Wusuli raccoon dogs were fed experimental diets with dry powder feed of ratio of food to water of 1∶2.5 (group Ⅰ),1∶3.5(group Ⅱ),1∶4.5 (group Ⅲ),respectively.The pre-test period lasted for 7 days and the trial period lasted for 67 days.The results showed that the average daily feed intake of each week from 11,12 to 13 weeks in groupⅠ was significantly less than that in groups Ⅱ and Ⅲ (P<0.05),the average daily feed intake of each week from 14,15 to 20 weeks was no significant difference among all groups (P>0.05).The total intake in group Ⅰ was significantly less than that in group Ⅱ (P<0.05).The average daily gain of each week from 15 to 17 weeks in group Ⅲ was significantly higher than that in group Ⅰ (P<0.05),while the average daily gain,total weight and the rate of feed intake to body gain in other week-old were no significant differences among all groups (P>0.05).The protein digestibility,fat digestibility and dry matter digestibility were no significant differences among all groups (P>0.05).The amount of urine in group Ⅲ was extremely significantly higher than that in groups Ⅰ and Ⅱ (P<0.01).The nitrogen intake,fecal nitrogen,urine nitrogen,nitrogen deposition,net protein utilization and biological value of protein were no significant differences among all groups (P>0.05).In conclusion,the appropriate ratios of food to water of dry powder feed of growing Wusuli raccoon dogs was 1∶3.5 to 1∶4.5.  相似文献   

9.
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