No abstract

. 1997. Influence of stage of maturity on yield components and chemical composition of cereal grain silages. Can. J. Anim. Sci. 77: 259-267. The objectives of this study were to determine changes in yield of total grain, stem and leaf DM, leaf:stem ratio and chemical composition during the growth period (boot to softdough stage) and during ensiling of whole-crop barley (Hordeum vulgare L. 'Noble'), oats (Avena sativa L. 'Cascade'), triticale (X Triticosecale Rimpani Witt. 'Wapiti'), and a 1:1 barley (Noble):winter triticale (cv. Pika) mixture. Data for whole-crop cereals were compared with a second cut alfalfa (Medicago sativa L. 'Algonquin'). Crude protein and nitrate concentrations of all crops decreased with advancing maturity. Neutral detergent fiber (NDF), acid detergent fiber (ADF), and cellulose concentrations of all crops initially increased and then decreased with advancing maturity whereas acid detergent lignin (ADL) concentrations increased with advancing maturity. During the growth phase, oats and triticale had higher NDF and ADF concentrations, but by harvesting these differences had disappeared. Leaf as percentage of total DM and leaf:stem ratios were higher and the stem as percentage of total DM was lower for the barley:winter triticale mixture compared with the cereal monocrops. Cereal forages were ranked in order of decreasing quality as barley, barley:winter triticale, triticale, and oats.Key words: Alfalfa, barley, oats, triticale, silage, quality Khorasani, G. R., Jedel, P. E., Helm, J. H. et Kennelly, J. J. 1997. Influence du stade de croissance sur les composantes du rendement et sur la composition chimique des ensilages de céréales plante entière. Can. J. Anim. Sci. 77: 259-267. L'objet de nos travaux était de suivre l'évolution du rendement total en grain, en tiges et en feuilles des céréales, ainsi que celle du rapport feuilles-tiges et de la composition chimique durant la période de croissance soit de la fin montaison au stade pâteux mou et durant la conservation en silo. Les céréales plante entière considérées étaient l'orge (Hordeum vulgare L. 'Noble'), l'avoine (Avena sativa L. 'Cascade'), le triticale (X Triticosecale Rimpani Witt. 'Wapiti') et une association à parts égales d'orge (Noble) et de triticale d'hiver (Pika). Les données recueillies étaient comparées à celles d'un premier regain de luzerne (Medicago sativa L. 'Algonquin'). Les concentrations de protéines et de nitrates dans toutes les cultures diminuaient en fonction du degré d'avancement de la végétation. Après une hausse initiale, les concentrations de fibres au détergent neutre (NDF), de lignocellulose (ADF) et de cellulose diminuaient avec l'avancement de la culture alors que les teneurs en LDA (lignine au détergent acide) augmentait régulièrement tout au long de la croissance. Durant la phase de croissance, l'avoine et le triticale révélaient des concentrations de NDF et de lignocellulose plus élevées, mais à la récolte ces différences avaient disparu. La part des feuilles dans le rendement total (m.s.) et le rappor...

that sufficient compaction occurs for exclusion of O 2 , that the fermentation processes of ensiling occur, and Cereals are an important substrate for silage production in the that overheating does not occur. However, moisture short growing season of the northern Prairies. Our objectives were to determine the effects of seeding rate, species, and harvest date contents Ͼ700 g kg Ϫ1 can lead to seepage problems from on the forage yield and quality of cereals. Three field studies were the silo or pit, nutrient loss due to leakage, dilution of conducted to evaluate the productivity of barley (Hordeum vulgare acid levels, and poor preservation of the silage. Ensiling L.), oat (Avena sativa L.), triticale (ϫ Triticosecale rimpaui Wittm.), does not increase the quality of the feedstuffs, so it is and rye (Secale cereale L.) grown as monocrops or in various mixtures.important that high-quality material is put into the silo. Seeding rates ranged from 250 to 750 seeds m Ϫ2 . Harvest times wereThe value of high-quality forage for high production based on the maturity of the principal cereal in each mixture. Few rates from ruminant animals was discussed by Waldo effects of seeding rate on yield or quality were found, but when effects and Jorgensen (1981) and Linn and Martin (1989). Highwere found, higher seeding rates were associated with higher yields, quality forage must have high intake, digestibility, and lower moisture content, and higher fiber content. All treatments proefficiency of utilization. Cell walls are an important comduced high quality forage as measured by neutral detergent fiber (NDF), from 515 g kg Ϫ1 for early-harvested tests to 656 g kg Ϫ1 for ponent determining quality. They have a digestible and late-harvested tests, and acid detergent fiber (ADF) contents, from an indigestible fraction. Neutral detergent fiber content 310 g kg Ϫ1 for early-harvested tests to 387 g kg Ϫ1 for late-harvested is a measure of the total cell wall fraction. Acid detertests. Protein was low, ranging from 61.5 to 101.0 g kg Ϫ1 . Biomass gent fiber content is a measure of the indigestible fracyields ranged from 10.1 to 16.5 Mg ha Ϫ1 in the barley cultivar tests, tion. When cell wall content of feed is low, increased 7.0 to 18.5 Mg ha Ϫ1 in the spring cereal tests, and 10.8 to 12.2 Mg intake and digestibility by animals is expected. Protein ha Ϫ1 in the winter cereal tests. Although, some exceptions occurred, content is an important feed factor per se, with highforage yield and quality of cereal mixtures were generally intermediate quality feed having a high protein content. Chemical to monocrop production, especially for moisture and fiber content, composition and nutritive value of green plant material suggesting that planting species mixtures could extend the harvest can give useful information about the quality of the period and result in higher-quality silage.resulting silage (Kjos, 1990).Compositionally, legumes are known to have higher protein and lower cell wall fractions but higher lignin ral Development,

Increasing costs of N fertilizers and the negative impact of excessive N on the environment have made improvement in nitrogen use efficiency (NUE) a desirable goal in barley (Hordeum vulgare L.) breeding. Seventeen replicated trials, each consisting of 15 to 20 genotypes, were performed across different environments in Alberta, Canada from 1998 to 2007 to determine genetic variability in NUE. Further, 25 genotypes were grown at six environments in 2007 for analysis of the pattern of genotypic variation for NUE. Analysis of variance revealed significant effects of genotype and environment on NUE. The majority of the phenotypic variation in NUE was accounted for by genotypic variance and heritability estimates for this trait ranged from 0.5 to 0.86. Genotypes H97097001001, H96014002, ‘Vivar’, and ‘Xena’, were superior in NUE, yielding 47 to 48 kg kg−1 N as compared to about 35 kg kg−1 N yield for the relatively inefficient genotypes. There was no clear distinction between two‐rowed and six‐rowed types in NUE, but rather significant differences were observed among genotypes within each spike‐type group. Reduction in N fertilizer requirements in barley while maintaining yield may be achieved through breeding by targeting increased yield potential in association with higher NUE.

The objective of the study was to evaluate the effect of barley and corn grains differing in expected fermentability in the rumen on dry matter intake (DMI) and productivity of lactating dairy cows. Twenty-two multiparous and 9 primiparous lactating Holstein cows (94 +/- 29 d in milk; mean +/- SD) were used in a 3 x 3 Latin square design with 21-d periods. Experimental diets contained approximately 40% of dietary dry matter as steam-rolled barley, using a lot of cultivar Dillon or cultivar Xena, or a corn mixture (CM) containing 87.5% dry ground corn, 11.4% beet pulp, and 1.1% urea (dry matter basis). Starch concentration of the grain sources was 50.0, 58.7, and 60.4% and in vitro 6-h starch digestibility was 73.5, 78.0, and 71.0%, respectively, for Dillon, Xena, and CM. All diets were formulated to contain 19.4% crude protein and 25.3% forage neutral detergent fiber. Dry matter intake (23.6 vs. 21.6 kg/d) and yields of milk (40.4 vs. 37.4 kg/d), milk protein (1.20 vs. 1.12 kg/d), and milk lactose (1.85 vs. 1.74 kg/d) were higher for cows fed CM than for cows fed barley. Although DMI was similar for cows fed Xena and Dillon (21.9 vs. 21.4 kg/d), cows fed Xena had higher yields of milk (38.5 vs. 36.2 kg/d), milk protein (1.18 vs. 1.07 kg/d), and milk lactose (1.80 vs. 1.69 kg/d) than cows fed Dillon. However, milk fat concentration tended to be higher (3.47 vs. 3.23%) for cows fed Dillon than Xena. Plasma glucose and nonesterified fatty acid concentrations were not affected by treatment, but plasma insulin concentration was higher for cows fed Xena compared with those fed Dillon (8.50 vs. 5.91 microIU/mL). Greater milk production for cows fed CM can be attributed to greater DMI. Feeding barley that was lower in starch concentration and ruminal starch fermentability (Dillon) did not increase DMI compared with feeding barley that was higher in starch concentration and ruminal starch fermentability (Xena). Reducing ruminal starch degradation of barley grain may not improve the productivity of lactating dairy cows.