QTL Analysis for Traits Associated with Feeding Value of Straw in Rice (Oryza sativa L.)

Genetic improvement of the digestibility of rice straw for increasing the utilization of the whole rice plant as feedstuffs is an important way to solve the feedstuffs shortage in southeastern China. To elucidate the genetic basis of the traits affecting the digestibility of rice straw, a rice population of 111 recombinant inbred lines （RILs） derived from a cross of Nekken 2xGaya was used to map the quantitative traits loci （QTLs） for in vitro dry matter digestion （IVDMD）, the percentages of nonstructural carbohydrate （NSC） and acid detergent fiber （exclusive of residual ash, ADFom） in 2005 and 2006. IVDMD was positively correlated with NSC, and negatively correlated with ADFom. A total of 16 QTLs were detected in the two years, and the amounts of variation explained by individual QTLs ranged from 6.9% to 15.5%. Some QTLs for IVDMD and ADFom on chromosome 2 were detected in the two years. On chromosome 2, the interval RM475-RM3515 contained QTLs for IVDMD in the two years and for NSC in 2006 only, while the interval RM3874-RM5305 influenced ADFom in the two years and NSC in 2005 only. At those loci, Gaya contributed favorable alleles to IVDMD and NSC, while Nekken 2 contributed positive alleles to ADFom.

Impacts of Different Stages of Nitrogen Dressing on Feeding Value of Forage Summer Maize

A trial of investigating impacts of nitrogen dressing at different stage on feeding value and physiological characteristics of forage summer maize (Ludan50) has been conducted by means of potted planting. The results suggested that biomass yield, grains yield and feeding value of all treatments were significantly raised compared CK without nitrogen dressing. Nitrogen dressing at the jointing stage for one time could raise the dry matter yield in terms of biomass, thus improving feeding value. Separating total dose of dressing nitro-

Relative Feed Value of Different Varieties of Dactylis glomerata and Festuca pratensis

The aim of this paper is to analyze fluctuation in nutritional value of Dactylis glomerata and Festuca pratensis varieties grown on mineral and organic soil. Moreover, the paper deals with analysis of their nutritional value in terms of animal feeding. This paper has drawn on two field experiments set up and carried out between 2010 and 2013 by the Research Centre for Cultivar Testing in Slupia Wielka. The experiment was conducted in two experimental stations： one in the Research Centre for Cultivar Testing in Krzyzewo and the other in the Experimental Stations for Variety Testing in Uhinin, being a branch of the Research Centre for Cultivar Testing in Cicibor Duzy. The experiment was arranged and conducted according to COBORU guidelines. The experimental plots were sown with varieties of Dactylis glornerata： Niva, Tukan, Amila, Crown Royale and with varieties of Festuca pratensis： Limosa, Pasja, Anturka, Amelka （d. AND 1009）. In the experimental plots with the varieties of Dactylis glornerata the grass was harvested six times a year and chemical analysis of the biomass was done taking dry matter only from five cuts. The varieties of Festuca pratensis were harvested four times. The RFV （relative feed value） was determined using the Linn and Martin method. Linn and Martin＇s test proved that Festuca pratensis had better nutritional value than Dactylis glomerata. For Dactylis glomerata, no matter what the variety and location was, the relative feed value ranged from 125 to 151, which puts that grass species in II quality class, good enough to feed high production dairy cows and heirs selected for replacements. The analysis of the relative feed value proved that no matter from which cut, the biomass ofDactylis glornerata belonged in Ill quality class, （RFV between 103 and 124） and it can be used to feed good beef cattle, older heifers and, in small quantities, dairy cows.

Madagascar High Lands Dry Season Forages： Lofium multiflorum （Italian Ray Grass） and Avena sativa （Oat）

Italian ray grass and oat are two grass species characterized by their ability to adjust tropical climate conditions. This study proposed to assess forage productivities to allow an appropriate mowing period determination in their use as dairy female feed in Madagascar. A test on small plots has been set up in the southern part of the capital city Antananarivo during one dry period （4 months）. Live observations followed by laboratory proximate analyses have been performed for forage productivity and feeding value determination. Cultivated on tanety （hill）, irrigated in counter season, results show that： （I） oat higher height （H = 96.7 cm） than Italian ray grass （H= 69.4 cm） at 99 days of age; （2） similar biomass productivity; （3） dry matter yields significantly different （p = 0.05）; （4） certain similarity between dry matter yields and FMU （fodder milk unit） score evolution; （5） leafy stage of Italian ray grasses at 99 days of age; （6） mid-flowering stage for oats during the same period. Cell wall content, crude fiber and dry matter contents increased with age （p = 0.05）. Crude proteins and minerals evolved in opposite directions. Gross energy content did not present precise variation with age. This study allowed that for an acceptable quantitative and qualitative production during dry seasons, good mowing period for Italian ray grass could start at 76 days age, while oat could start being harvested at 68 days.

Nutritional Evaluation and Palatability of Major Range Forbs from South Darfur, Sudan

The nutritive value of rangelands in Southern Darfur, Sudan could be improved by introduction and multiplication of nutritious forbs with the objective of increasing livestock production in the area. The present study was conducted to evaluate the nutritive value and palatability of eleven range forbs collected at flowering stage from Gahzal Gawazat, Southern Darfur, Sudan using chemical analysis. The crude protein (CP) ranged from 6.8% in Oxygonum atriplicifolium with lowest digestible crude protein (DCP) 2.8% to 16.4% in Zornia diphylla with highest DCP 11.73%. The highest and the lowest crude fiber (CF) values were obtained in Commelina spp (56.4%) and Sesamum alatum (25.9%), respectively. NDF and DMI values were maximum and minimum for Zornia diphylla (44.9 and 2.67%) and Alysicarpus glumaceus (35.3 and 3.4%), respectively. The total digestible nutrients (TDN) ranged from 57.1% in Blepharis linariifolia to 69.3% in Tribulus terrestris with highest digestible energy (DE) in later while the lowest DE was obtained in Commelina spp (2.4%). The calculated in vitro organic matter digestibility (IVOMD) was highest for the Canavalia ensiformis (50.27%) and lowest value (43.17%) for Commelina spp. Zornia diphylla, Tribulus terrestris and Sesamum alatum showed highest nutritive value, while Alysicarpus glumaceus, Oldenlandia senegalensis and Chrozophora brocchiana showed highest palatability. It is concluded that these rangeland forbs are palatable and their CP and energy contents are sufficient to support different classes of livestock in South Darfur, Sudan.