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, J. 2004. Cropping systems for annual forage production in northeast Saskatchewan. Can. J. Plant Sci. 84: [187][188][189][190][191][192][193][194]. Herbage production for silage and pasture production of annual species was investigated near Melfort in northeastern Saskatchewan. Barley (Hordeum vulgare L.) and oats (Avena sativa L.) were seeded as spring monocrops (SMC) and in binary intercrop (IC) mixtures with fall species including winter wheat (Triticum aestivum L.), fall rye (Secale cereale L.), winter triticale (X Triticosecale Wittmack L.), biennial Italian ryegrass (Lolium multiflorum Lam.) and annual Westerwolds ryegrass (Lolium multiflorum Lam.). Fall species were also seeded as monocrops (FMC). Silage Spring harvest occurred when barley (early-silage cut) and oats (late-silage cut) reached soft dough stage and again late in the autumn. An additional deferred grazing (DG) treatment containing each one fall species was harvested once in the autumn. Mean ranking of spring herbage silage yield was Oat-SMC (100%) > Oat-IC (91%) > Barley-SMC (83%) = Barley-IC (78%) > late-cut FMC (53%) > early-cut FMC (42%) (P ≤ 0.001). SilageSpring herbage yield of IC combinations was similar, but FMCs containing annual ryegrass were 26% to 34% (P ≤ .01) greater than other treatments. Crude protein content (g kg -1 ) was 14 to 35% higher (P ≤ 0.001) in IC systems than the corresponding SMC. Neutraleutral detergent fibre (NDF) and acid detergent fibre (ADF) content (g kg -1 ) of barley based systems was 15 and 22% lower (P ≤ 0.001) than those with oats. Ranking and relative productivity for fall pasture was DG (100%) > early-cut FMC (67%) > late-cut FMC (49%) > Barley-IC (30%) > Oat-IC (24%) = Barley-SMC (14%) (P ≤ 0.001). Cropping systems that contained no spring cereal produced 2.37-fold higher (P ≤ 0.001) fall pasture yield than those with spring cereals. Among FMCs, ICs and DG systems, mean yield of ryegrass treatments were generally higher (P ≤ 0.05) than that of fall cereals. . La récolte a eu lieu quand l'orge (coupe hâtive) et l'avoine (coupe tardive) avaient atteint le stade pâteux mou puis de nouveau à la fin de l'automne. On a aussi essayé un régime de mise à l'herbe tardive (MHT) en vertu duquel chaque espèce automnale a été récoltée une fois à l'automne. Le rendement printanier moyen en herbages se classe comme suit : avoine-MCP (100 %) > avoine CI (91 %) > orge-MCP (83 %) = orge-CI (78 %) > MCA coupe tardive (53 %) > MCA coupe hâtive (42 %) (P ≤ 0,001). Les combinaisons CI donnent un rendement printanier en herbages similaire, mais le rendement de la MCA de ray-grass annuel dépasse le rendement des autres régimes de 26 à 34 % (P ≤ 0,01). Les systèmes à CI se caractérisent par une concentration de protéines brutes (en g par kg) de 14 à 35 % plus élevée (P ≤ 0,001) que les régimes MCP correspondants. Les systèmes à base d'orge donnent une teneur en fibres au détergent neutre (FDN) et en fibres au détergent acide (FDA) (en g par kg) de 15 % et de 22 % inférieure à celle des systèmes à base d'avoine. Le classement...

. Effect of prolonged backgrounding on growth performance and carcass composition of crossbred beef steers. Can. J. Anim. Sci. 78: 359-367. One hundred and twenty crossbred steers were fed to slaughter on a high-energy finishing ration (GRAIN), or given barley silage during the winter, grazed 90 d, and then finished on the high-energy ration (FORAGE) to determine the effect of prolonged backgrounding on growth performance and carcass composition. The steers were separated into two weight groups (light vs. heavy, 346 ± 19 vs. 394 ± 16 kg; P < 0.01) and allocated to a feeding program across 12 pens according to a 2 × 2 factorial completely randomized design. The steers were slaughtered by pen at an average USFAT depth of 8 mm. Compared with steers on the GRAIN program, FORAGE steers had lower average daily gains (1.03 vs. 1.62 kg d -1 ; P < 0.01), took 119 d longer to finish (P < 0.01) and finished at heavier live (626 vs. 578 kg; P < 0.01), and carcass (342 vs. 306 kg; P < 0.01) weights. Heavy animals grew faster (1.37 vs. 1.28 kg d -1 , P < 0.01), and were slaughtered 15 d earlier (P < 0.06) at heavier weights (626 vs. 578 kg; P < 0.01) than light animals. Light animals had smaller l. thoracis area than heavy animals (86.8 vs. 93.8 cm 2 ; P < 0.01). The proportion of carcasses with slight or small marbling was greater (P < 0.01) for light steers, particularly those with a higher proportion of "British" breeding. Prolonged backgrounding with forages produced larger carcasses without adversely affecting composition. préfinition prolongée sur la croissance et sur la composition de la carcasse. Les animaux étaient divisés par groupe de poids : léger 346 ± 19 et lourd 394 ± 16 kg (P < 0,01) et répartis en 12 parquets selon un dispositif factoriel 2 × 2 en blocs aléa-toires complets. L'abattage par parquet se faisait lorsque l'épaisseur du lard dorsal à la douzième côte, mesuré par ultrasons était de 8 mm. Par rapport à ceux du régime GRAIN, les bouvillons de longue préfinition manifestaient un GMQ moindre (1,03 contre 1,62 kg j -1 ), prenaient 119 jours de plus à engraisser (P < 0,01) et atteignaient un poids vif et un poids de carcasse plus élevés à l'abattage, soit respectivement 626 contre 578 kg et 342 contre 306 kg, P < 0,01. Les sujets de type lourd croissaient plus rapidement (1,37 contre 1,28 kg j -1 , P < 0,01) et étaient abattus 15 jours plus tôt (P < 0,06) à un poids plus élevé (626 contre 578 kg, P < 0,01) que ceux de type léger. Ces derniers révélaient une plus petite surface de la noix de côte (longissimus thoracis) que ceux de type lourd, soit 86,8 contre 93,8 cm 2 (P < 0,01). La proportion des carcasses à persillé léger ou faible était plus grande (P < 0,01) chez les bouvillons de type léger, surtout chez ceux à forte ascendance de race britannique. La préfinition prolongée aux fourrages grossiers donnait lieu à des carcasses plus développées, sans pour autant nuire à leur composition.Mots clés: Préfinition prolongée, bouvillon de type à viande, composition de la carcasse Backgrounding involves raisin...

Rumen epithelial papillae samples, acquired from the Central sac of six adult Hereford steers (585 +/- 17 kg) fed either timothy hay plus soybean meal (T) or timothy hay plus cracked corn and soybean meal (TC) once daily (0900), were used in a crossover design to study the daily pattern of O2 consumption and protein synthesis. Tissue samples were acquired at 0900, 1200, 1800, and 2400 over a 10-d sampling period. Additionally, ruminal fermentation characteristics (pH, ammonia, VFA, and osmolality) were measured at 0430, 0900, 1030, 1200, 1500, 1800, 2100 and 2400. Total, ouabain-insensitive (OIO2), and cycloheximide-insensitive (CIO2) O2 consumption were greatest at 2400 (P < .01, P < .06, and P < .02 respectively). Additionally, steer fed TC had a greater CIO2 at 2400. In conjunction with a temporal effect on ruminal fermentation patterns, after an initial decline, there was an increase (P < .05) in total O2, ouabain-sensitive (OSO2), OIO2, and CIO2 consumption throughout the day. Fractional rates of protein synthesis were not different at any time point between diets. Rumen epithelial metabolism exhibits a temporal pattern in cattle fed once daily.

The mat meter (Fig. la) The voltage divider circuit (Fig. lb) (Fig. lc)