The development of short-season hybrids has made corn (Zea mays L.) silage (CS) production possib... more The development of short-season hybrids has made corn (Zea mays L.) silage (CS) production possible in cooler areas. This work aimed at determining biomass yield and nutritive quality of short-season corn CS hybrids. Six corn hybrids were grown in three years at four locations within the Canadian prairies with four field replications. Hybrids were harvested before occurrence of frost at a target dry matter (DM) content of 300 to 400 g kg−1. Corn heat units (CHU) from seeding to harvesting (CHUseed-harv) and water supply were recorded. Samples were analysed for nutrient content; i.e., DM, neutral detergent fiber (NDF), crude protein (CP), starch, and in vitro DM and NDF digestibilities (48 h incubation). Then, CHUseed-harv, water supply, whole plant DM, CHU rating of the hybrid, and cob percentage were assessed as predictors of nutrient content. Location, hybrid, and year affected nutrient composition and yield. Overall, CP and NDF were positively correlated (r = 0.48, p < 0.01), ...
Doce, R. R., Baron, V. S., and Dick, A. C. 2015. Estimating swath-grazed carrying capacity from p... more Doce, R. R., Baron, V. S., and Dick, A. C. 2015. Estimating swath-grazed carrying capacity from plot-scale data. Can. J. Plant Sci. 95: 647–651. A spreadsheet calculator was developed to estimate farm-scale carrying capacities for swath grazing beef cows with forage yield and quality data from small areas within fields or paddocks. It could be used to compare agronomic treatments for swath grazing potential from plot data when combined with existing beef nutrition equations. Examples using either in vitro true digestibility at 30-h digestion or acid detergent fiber (ADF) in equations to estimate digestible energy were compared with actual field-scale carrying capacities to evaluate the ability of the methods to meet requirements of scale, precision and accuracy. Both methods were capable of estimating carrying capacity at a realistic whole-farm scale, but the ADF-based method was superior with respect to accuracy and precision characteristics.
Manafiazar, G., Basarab, J. A., Baron, V. S., McKeown, L., Doce, R. R., Swift, M., Undi, M., Witt... more Manafiazar, G., Basarab, J. A., Baron, V. S., McKeown, L., Doce, R. R., Swift, M., Undi, M., Wittenberg, K. and Ominski, K. 2015. Effect of post-weaning residual feed intake classification on grazed grass intake and performance in pregnant beef heifers. Can. J. Anim. Sci. 95: 369–381. There is limited knowledge of how cattle tested for feed efficiency under drylot conditions perform when they graze on summer pasture. Residual feed intake adjusted for end of test backfat thickness (RFIfat) was determined on 171 beef crossbred heifers under drylot conditions over 2 yr using an automated system. Upon completion of the test, the 10 lowest and 10 highest RFIfat (–0.54±0.17 vs. 0.58±0.15 kg DM d−1) heifers in 2012, and the 14 lowest and 14 highest RFIfat (−0.47±0.16 vs. 0.53±0.19 kg DM d−1) heifers in 2013 were selected and placed on meadow bromegrass pasture to investigate the effect of RFIfat ranking on their grass intake and performance on the pasture. The pasture adaptation period (8 ...
Spring-planted mixtures of spring and winter cereals in a silage/fall pasture system have been sh... more Spring-planted mixtures of spring and winter cereals in a silage/fall pasture system have been shown to extend the grazing season in the Parkland of the Canadian prairies. Experiments were conducted at Lacombe, Alberta to determine the effects of planting date on yield and yield components of spring-seeded spring oat (Avena sativa L.), winter wheat (Triticum aestivum L.), winter triticale (X Triticosecale Wittmack) and winter rye (Secale cereale L.). The cereals were grown as monocrops or as binary mixtures of the oat and winter cereals. Treatments were planted in early May and mid-June and harvested twice for forage. The initial harvest for early and late planting dates occurred when oat reached the early-milk and heading stages, respectively. Regrowth was harvested in mid- to late September. The planting date x treatment interaction did not affect (P ≤ 0.05) annual yield (initial + regrowth) even though oat was harvested at different developmental stages. Averaged over treatments,...
The response in composition, in vitro dry matter digestibility (IVDDM), and enzymatic saccharific... more The response in composition, in vitro dry matter digestibility (IVDDM), and enzymatic saccharification, of alfalfa and various grasses to selective solvent delignification (SSD), as well as the nutritive value of the residual biomass (co-product), was determined. The SSD pretreatment reduced lignin concentrations in grasses but not in alfalfa. Associated effects were increases in concentrations of neutral detergent fiber (NDF) due
Regrowth in pastures is critical to economic production in short‐season areas. This study compare... more Regrowth in pastures is critical to economic production in short‐season areas. This study compared regrowth characteristics among three Bromus genotypes and meadow foxtail (Alopecurus pratensis L.) during late summer and fall. Growth analyses were conducted and yield components were determined in ‘Carlton’ smooth bromegrass (B. inermis Leyss.), ‘Regar’ meadow bromegrass (B. riparius Rhem.), an experimental strain (S9044) derived from F2 plants of a smooth ✕ meadow bromegrass cross, and common meadow foxtail. Seven weeks of plant regrowth after severe defoliation were characterized during 1985 and 1986 at Lacombe, AB, Canada (52° 28' N lat). The variation among the three grass species and the interspecific hybrid that was most critical to regrowth yield occurred during the first 21 to 28 d after defoliation. Smooth bromegrass consistently yielded less dry matter (DM) and had lower crop growth rates (CGR) than the other genotypes. Smooth bromegrass seemed limited most by a slowly ...
Currently, there is interest in Western Canada in extending the grazing season using perennial an... more Currently, there is interest in Western Canada in extending the grazing season using perennial and annual forages. Of greatest concern is the environmental sustainability of these grazing systems, with emphasis on their ability to withstand erosion. A study to examine the runoff and sediment yields of annual and perennial forages in central Alberta was initiated in 1994. Runoff and sediment yield were quantified under snowmelt and rainfall events for two seasons. Rainfall simulation was used to further examine runoff under growing season conditions. Four forage treatments (two annuals: triticale and a barley/triticale mixture and two perennials: smooth bromegrass and meadow bromegrass) and three grazing intensities (light, medium and heavy) were studied, each replicated four times. Total annual runoff was dominated by snowmelt. Generally runoff volumes, sediment yields, sediment ratios and runoff coefficients were all low. Bare ground increased with increasing grazing intensity and ...
Increasing yield for silage and grazing in cool, short-season areas may be possible by planting c... more Increasing yield for silage and grazing in cool, short-season areas may be possible by planting corn (Zea mays L.) at high population densities and at narrow row spacing. The objective was to determine how population density (75 000, 100 000, and 125 000 plants ha-1) and row spacing (standard: 76 cm and narrow: 38 cm) affected whole-plant yield, yield-related parameters, and nutritive value of two corn hybrids grown at Brooks and Lacombe, Alberta during 2 yr. The hybrids (Pioneer 39F45 and 39N03) were rated at 2000 Ontario corn heat units (CHU). Trial, hybrid, population density and row spacing interacted to influence whole-plant yield. Population density had a greater impact on whole-plant yield than row spacing and hybrid choice. Generally, yield leveled off at 100 000 plants ha-1 when the interaction of all effects was considered. Leaf area index (LAI) and whole-plant yield at this density were 2.68 and 12.0 Mg ha-1, respectively. Narrow compared with standard row spacing had pos...
The aim of this study was to identify SNP markers that associate with variation in beef heifer re... more The aim of this study was to identify SNP markers that associate with variation in beef heifer reproduction and performance of their calves. A genome-wide association study was performed by means of the generalized quasi-likelihood score (GQLS) method using heifer genotypes from the BovineSNP50 BeadChip and estimated breeding values for pre-breeding body weight (PBW), pregnancy rate (PR), calving difficulty (CD), age at first calving (AFC), calf birth weight (BWT), calf weaning weight (WWT), and calf pre-weaning average daily gain (ADG). Data consisted of 785 replacement heifers from three Canadian research herds, namely Brandon Research Centre, Brandon, Manitoba, University of Alberta Roy Berg Kinsella Ranch, Kinsella, Alberta, and Lacombe Research Centre, Lacombe, Alberta. After applying a false discovery rate correction at a 5% significance level, a total of 4, 3, 3, 9, 6, 2, and 1 SNPs were significantly associated with PBW, PR, CD, AFC, BWT, WWT, and ADG, respectively. These SN...
A series of studies was conducted to determine the efficacy and possible modes of action of a wat... more A series of studies was conducted to determine the efficacy and possible modes of action of a water-soluble mixture of alcohol ethoxylate and pluronic detergents (AEPD; Blocare 4511, ANCARE, Auckland, NZ) in preventing pasture bloat in ruminants grazing or fed freshly harvested alfalfa. Ten cannulated Suffolk wethers were offered freshly harvested alfalfa; five were given a daily intraruminal dose of 40 ml of 50% AEPD (vol/vol) 1 h before feeding, and five (controls) were dosed with water. Viscosity of ruminal fluid was reduced (P < 0.001) in AEPD-treated wethers, relative to the controls, for the first 2 h after feeding but not at 4 h after feeding and beyond. Treatment with AEPD did not affect dry matter (DM) intake, digestibility of DM, acid detergent fiber, or neutral detergent fiber, or N digestion and retention, implying that AEPD likely would not affect milk production. In a crossover grazing study, five of the wethers were given AEPD in drinking water (0.1%, vol/vol); tre...
The current study compared beef production, quality and fatty acid (FA) profiles of yearling stee... more The current study compared beef production, quality and fatty acid (FA) profiles of yearling steers fed a control diet containing 70 : 30 red clover silage (RCS) : barley-based concentrate, a diet containing 11% sunflower seed (SS) substituted for barley, and diets containing SS with15% or 30% wheat dried distillers’ grain with solubles (DDGS). Additions of DDGS were balanced by reductions in RCS and SS to maintain crude fat levels in diets. A total of two pens of eight animals were fed per diet for an average period of 208 days. Relative to the control diet, feeding the SS diet increased (P<0.05) average daily gain, final live weight and proportions of total n-6 FA, non-conjugated 18:2 biohydrogenation products (i.e. atypical dienes) with the first double bond at carbon 8 or 9 from the carboxyl end, conjugated linoleic acid isomers with the first double bond from carbon 7 to 10 from the carboxyl end,t-18:1 isomers, and reduced (P<0.05) the proportions of total n-3 FA, conjuga...
The American journal of clinical nutrition, Jun 1, 2004
Canadian beef consumption is approximately 31 kg per annum, or a third of all meats consumed. Bee... more Canadian beef consumption is approximately 31 kg per annum, or a third of all meats consumed. Beef is a nutrient-rich food, providing good quality protein, vitamins B-6 and B-12, niacin, iron, and zinc. However, animal fats have gained the reputation of being less healthy. The identification of the anticarcinogenic effects of beef extracts due to the presence of conjugated linoleic acid (CLA) has heightened interest in increasing the amount of CLA deposited in beef. Beef cattle produce CLA and deposit these compounds in the meat; thus, beef consumers can receive bioformed CLA. Beef contains both of the bioactive CLA isomers, namely, cis-9, trans-11 and trans-10, cis-12. The relative content of these CLA isomers in beef depends on the feeds consumed by the animals during production. Feeding cattle linoleic acid-rich oils for extended periods of time increases the CLA content of beef. Depending on the type and relative maturity of the pasture, beef from pasture-fed cattle may have a h...
To elucidate the effects of dietary vitamin E with or without flaxseed on beef fatty acid composi... more To elucidate the effects of dietary vitamin E with or without flaxseed on beef fatty acid composition, 80 feedlot steers were fed 4 diets: Control-E (451 IU dl-α-tocopheryl acetate/head/day), Control+E (1051 IU dl-α-tocopheryl acetate/head/day), Flax-E (10% ground) and Flax+E. Vitamin E had no effect on animal growth or carcass weight (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;0.05), while flaxseed-fed steers had greater average daily gain (p=0.007), final live weight (p=0.005) and heavier carcasses (p=0.012). Feeding flaxseed increased the total n-3 fatty acid content of beef and this response was further accentuated by the inclusion of high levels of vitamin E in the diet. Feeding flax increased levels of some 18:3n-3 partial hydrogenation products including c15- and t13/14-18:1 and several 18:2 isomers (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001) but decreased t10-18:1 (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). Vitamin E enhanced intramuscular levels of 18:3n-3 and its biohydrogenation products leading to greater accumulations of total n-3 fatty acids in lean ground beef. The consequences of increasing the concentrations of partially hydrogenated products on human health have yet to be investigated.
In order to investigate the effects of increasing beef n-3 fatty acid content and the protective ... more In order to investigate the effects of increasing beef n-3 fatty acid content and the protective effects of vitamin E antioxidant activity on meat quality characteristics, 80 feedlot steers were fed 4 different diets (control, high vitamin E, 10% ground flaxseed or high vitamin E-10% ground flaxseed). While dietary treatments had no effect (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;0.05) on meat composition or tenderness values, the increase in oxidation products was lower (P=0.046) in meat from vitamin E supplemented steers and higher (P=0.006) in meat from flaxseed fed animals. The increase in α-tocopherol tissue levels (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001) in meat from animals fed flaxseed and increased dietary vitamin E resulted in the lowest drip loss values (P=0.013). As expected, display time had a large effect on retail traits in both steaks and patties (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). While retail traits of steaks were not affected by the dietary treatments (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;0.05), feeding flaxseed decreased (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.05) ground beef retail scores, which were not corrected by higher levels of dietary vitamin E. Finally, although no effect (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;0.05) was observed among treatments for sensory attributes in steaks, the correlations of a combined n-3:α-tocopherol ratio against retail and sensory attributes (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.05) suggest that increased n-3 fatty acids levels require increased dietary antioxidants, such as vitamin E to avoid negative effects on meat quality from a loss in oxidative stability.
The development of short-season hybrids has made corn (Zea mays L.) silage (CS) production possib... more The development of short-season hybrids has made corn (Zea mays L.) silage (CS) production possible in cooler areas. This work aimed at determining biomass yield and nutritive quality of short-season corn CS hybrids. Six corn hybrids were grown in three years at four locations within the Canadian prairies with four field replications. Hybrids were harvested before occurrence of frost at a target dry matter (DM) content of 300 to 400 g kg−1. Corn heat units (CHU) from seeding to harvesting (CHUseed-harv) and water supply were recorded. Samples were analysed for nutrient content; i.e., DM, neutral detergent fiber (NDF), crude protein (CP), starch, and in vitro DM and NDF digestibilities (48 h incubation). Then, CHUseed-harv, water supply, whole plant DM, CHU rating of the hybrid, and cob percentage were assessed as predictors of nutrient content. Location, hybrid, and year affected nutrient composition and yield. Overall, CP and NDF were positively correlated (r = 0.48, p < 0.01), ...
Doce, R. R., Baron, V. S., and Dick, A. C. 2015. Estimating swath-grazed carrying capacity from p... more Doce, R. R., Baron, V. S., and Dick, A. C. 2015. Estimating swath-grazed carrying capacity from plot-scale data. Can. J. Plant Sci. 95: 647–651. A spreadsheet calculator was developed to estimate farm-scale carrying capacities for swath grazing beef cows with forage yield and quality data from small areas within fields or paddocks. It could be used to compare agronomic treatments for swath grazing potential from plot data when combined with existing beef nutrition equations. Examples using either in vitro true digestibility at 30-h digestion or acid detergent fiber (ADF) in equations to estimate digestible energy were compared with actual field-scale carrying capacities to evaluate the ability of the methods to meet requirements of scale, precision and accuracy. Both methods were capable of estimating carrying capacity at a realistic whole-farm scale, but the ADF-based method was superior with respect to accuracy and precision characteristics.
Manafiazar, G., Basarab, J. A., Baron, V. S., McKeown, L., Doce, R. R., Swift, M., Undi, M., Witt... more Manafiazar, G., Basarab, J. A., Baron, V. S., McKeown, L., Doce, R. R., Swift, M., Undi, M., Wittenberg, K. and Ominski, K. 2015. Effect of post-weaning residual feed intake classification on grazed grass intake and performance in pregnant beef heifers. Can. J. Anim. Sci. 95: 369–381. There is limited knowledge of how cattle tested for feed efficiency under drylot conditions perform when they graze on summer pasture. Residual feed intake adjusted for end of test backfat thickness (RFIfat) was determined on 171 beef crossbred heifers under drylot conditions over 2 yr using an automated system. Upon completion of the test, the 10 lowest and 10 highest RFIfat (–0.54±0.17 vs. 0.58±0.15 kg DM d−1) heifers in 2012, and the 14 lowest and 14 highest RFIfat (−0.47±0.16 vs. 0.53±0.19 kg DM d−1) heifers in 2013 were selected and placed on meadow bromegrass pasture to investigate the effect of RFIfat ranking on their grass intake and performance on the pasture. The pasture adaptation period (8 ...
Spring-planted mixtures of spring and winter cereals in a silage/fall pasture system have been sh... more Spring-planted mixtures of spring and winter cereals in a silage/fall pasture system have been shown to extend the grazing season in the Parkland of the Canadian prairies. Experiments were conducted at Lacombe, Alberta to determine the effects of planting date on yield and yield components of spring-seeded spring oat (Avena sativa L.), winter wheat (Triticum aestivum L.), winter triticale (X Triticosecale Wittmack) and winter rye (Secale cereale L.). The cereals were grown as monocrops or as binary mixtures of the oat and winter cereals. Treatments were planted in early May and mid-June and harvested twice for forage. The initial harvest for early and late planting dates occurred when oat reached the early-milk and heading stages, respectively. Regrowth was harvested in mid- to late September. The planting date x treatment interaction did not affect (P ≤ 0.05) annual yield (initial + regrowth) even though oat was harvested at different developmental stages. Averaged over treatments,...
The response in composition, in vitro dry matter digestibility (IVDDM), and enzymatic saccharific... more The response in composition, in vitro dry matter digestibility (IVDDM), and enzymatic saccharification, of alfalfa and various grasses to selective solvent delignification (SSD), as well as the nutritive value of the residual biomass (co-product), was determined. The SSD pretreatment reduced lignin concentrations in grasses but not in alfalfa. Associated effects were increases in concentrations of neutral detergent fiber (NDF) due
Regrowth in pastures is critical to economic production in short‐season areas. This study compare... more Regrowth in pastures is critical to economic production in short‐season areas. This study compared regrowth characteristics among three Bromus genotypes and meadow foxtail (Alopecurus pratensis L.) during late summer and fall. Growth analyses were conducted and yield components were determined in ‘Carlton’ smooth bromegrass (B. inermis Leyss.), ‘Regar’ meadow bromegrass (B. riparius Rhem.), an experimental strain (S9044) derived from F2 plants of a smooth ✕ meadow bromegrass cross, and common meadow foxtail. Seven weeks of plant regrowth after severe defoliation were characterized during 1985 and 1986 at Lacombe, AB, Canada (52° 28' N lat). The variation among the three grass species and the interspecific hybrid that was most critical to regrowth yield occurred during the first 21 to 28 d after defoliation. Smooth bromegrass consistently yielded less dry matter (DM) and had lower crop growth rates (CGR) than the other genotypes. Smooth bromegrass seemed limited most by a slowly ...
Currently, there is interest in Western Canada in extending the grazing season using perennial an... more Currently, there is interest in Western Canada in extending the grazing season using perennial and annual forages. Of greatest concern is the environmental sustainability of these grazing systems, with emphasis on their ability to withstand erosion. A study to examine the runoff and sediment yields of annual and perennial forages in central Alberta was initiated in 1994. Runoff and sediment yield were quantified under snowmelt and rainfall events for two seasons. Rainfall simulation was used to further examine runoff under growing season conditions. Four forage treatments (two annuals: triticale and a barley/triticale mixture and two perennials: smooth bromegrass and meadow bromegrass) and three grazing intensities (light, medium and heavy) were studied, each replicated four times. Total annual runoff was dominated by snowmelt. Generally runoff volumes, sediment yields, sediment ratios and runoff coefficients were all low. Bare ground increased with increasing grazing intensity and ...
Increasing yield for silage and grazing in cool, short-season areas may be possible by planting c... more Increasing yield for silage and grazing in cool, short-season areas may be possible by planting corn (Zea mays L.) at high population densities and at narrow row spacing. The objective was to determine how population density (75 000, 100 000, and 125 000 plants ha-1) and row spacing (standard: 76 cm and narrow: 38 cm) affected whole-plant yield, yield-related parameters, and nutritive value of two corn hybrids grown at Brooks and Lacombe, Alberta during 2 yr. The hybrids (Pioneer 39F45 and 39N03) were rated at 2000 Ontario corn heat units (CHU). Trial, hybrid, population density and row spacing interacted to influence whole-plant yield. Population density had a greater impact on whole-plant yield than row spacing and hybrid choice. Generally, yield leveled off at 100 000 plants ha-1 when the interaction of all effects was considered. Leaf area index (LAI) and whole-plant yield at this density were 2.68 and 12.0 Mg ha-1, respectively. Narrow compared with standard row spacing had pos...
The aim of this study was to identify SNP markers that associate with variation in beef heifer re... more The aim of this study was to identify SNP markers that associate with variation in beef heifer reproduction and performance of their calves. A genome-wide association study was performed by means of the generalized quasi-likelihood score (GQLS) method using heifer genotypes from the BovineSNP50 BeadChip and estimated breeding values for pre-breeding body weight (PBW), pregnancy rate (PR), calving difficulty (CD), age at first calving (AFC), calf birth weight (BWT), calf weaning weight (WWT), and calf pre-weaning average daily gain (ADG). Data consisted of 785 replacement heifers from three Canadian research herds, namely Brandon Research Centre, Brandon, Manitoba, University of Alberta Roy Berg Kinsella Ranch, Kinsella, Alberta, and Lacombe Research Centre, Lacombe, Alberta. After applying a false discovery rate correction at a 5% significance level, a total of 4, 3, 3, 9, 6, 2, and 1 SNPs were significantly associated with PBW, PR, CD, AFC, BWT, WWT, and ADG, respectively. These SN...
A series of studies was conducted to determine the efficacy and possible modes of action of a wat... more A series of studies was conducted to determine the efficacy and possible modes of action of a water-soluble mixture of alcohol ethoxylate and pluronic detergents (AEPD; Blocare 4511, ANCARE, Auckland, NZ) in preventing pasture bloat in ruminants grazing or fed freshly harvested alfalfa. Ten cannulated Suffolk wethers were offered freshly harvested alfalfa; five were given a daily intraruminal dose of 40 ml of 50% AEPD (vol/vol) 1 h before feeding, and five (controls) were dosed with water. Viscosity of ruminal fluid was reduced (P < 0.001) in AEPD-treated wethers, relative to the controls, for the first 2 h after feeding but not at 4 h after feeding and beyond. Treatment with AEPD did not affect dry matter (DM) intake, digestibility of DM, acid detergent fiber, or neutral detergent fiber, or N digestion and retention, implying that AEPD likely would not affect milk production. In a crossover grazing study, five of the wethers were given AEPD in drinking water (0.1%, vol/vol); tre...
The current study compared beef production, quality and fatty acid (FA) profiles of yearling stee... more The current study compared beef production, quality and fatty acid (FA) profiles of yearling steers fed a control diet containing 70 : 30 red clover silage (RCS) : barley-based concentrate, a diet containing 11% sunflower seed (SS) substituted for barley, and diets containing SS with15% or 30% wheat dried distillers’ grain with solubles (DDGS). Additions of DDGS were balanced by reductions in RCS and SS to maintain crude fat levels in diets. A total of two pens of eight animals were fed per diet for an average period of 208 days. Relative to the control diet, feeding the SS diet increased (P<0.05) average daily gain, final live weight and proportions of total n-6 FA, non-conjugated 18:2 biohydrogenation products (i.e. atypical dienes) with the first double bond at carbon 8 or 9 from the carboxyl end, conjugated linoleic acid isomers with the first double bond from carbon 7 to 10 from the carboxyl end,t-18:1 isomers, and reduced (P<0.05) the proportions of total n-3 FA, conjuga...
The American journal of clinical nutrition, Jun 1, 2004
Canadian beef consumption is approximately 31 kg per annum, or a third of all meats consumed. Bee... more Canadian beef consumption is approximately 31 kg per annum, or a third of all meats consumed. Beef is a nutrient-rich food, providing good quality protein, vitamins B-6 and B-12, niacin, iron, and zinc. However, animal fats have gained the reputation of being less healthy. The identification of the anticarcinogenic effects of beef extracts due to the presence of conjugated linoleic acid (CLA) has heightened interest in increasing the amount of CLA deposited in beef. Beef cattle produce CLA and deposit these compounds in the meat; thus, beef consumers can receive bioformed CLA. Beef contains both of the bioactive CLA isomers, namely, cis-9, trans-11 and trans-10, cis-12. The relative content of these CLA isomers in beef depends on the feeds consumed by the animals during production. Feeding cattle linoleic acid-rich oils for extended periods of time increases the CLA content of beef. Depending on the type and relative maturity of the pasture, beef from pasture-fed cattle may have a h...
To elucidate the effects of dietary vitamin E with or without flaxseed on beef fatty acid composi... more To elucidate the effects of dietary vitamin E with or without flaxseed on beef fatty acid composition, 80 feedlot steers were fed 4 diets: Control-E (451 IU dl-α-tocopheryl acetate/head/day), Control+E (1051 IU dl-α-tocopheryl acetate/head/day), Flax-E (10% ground) and Flax+E. Vitamin E had no effect on animal growth or carcass weight (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;0.05), while flaxseed-fed steers had greater average daily gain (p=0.007), final live weight (p=0.005) and heavier carcasses (p=0.012). Feeding flaxseed increased the total n-3 fatty acid content of beef and this response was further accentuated by the inclusion of high levels of vitamin E in the diet. Feeding flax increased levels of some 18:3n-3 partial hydrogenation products including c15- and t13/14-18:1 and several 18:2 isomers (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001) but decreased t10-18:1 (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). Vitamin E enhanced intramuscular levels of 18:3n-3 and its biohydrogenation products leading to greater accumulations of total n-3 fatty acids in lean ground beef. The consequences of increasing the concentrations of partially hydrogenated products on human health have yet to be investigated.
In order to investigate the effects of increasing beef n-3 fatty acid content and the protective ... more In order to investigate the effects of increasing beef n-3 fatty acid content and the protective effects of vitamin E antioxidant activity on meat quality characteristics, 80 feedlot steers were fed 4 different diets (control, high vitamin E, 10% ground flaxseed or high vitamin E-10% ground flaxseed). While dietary treatments had no effect (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;0.05) on meat composition or tenderness values, the increase in oxidation products was lower (P=0.046) in meat from vitamin E supplemented steers and higher (P=0.006) in meat from flaxseed fed animals. The increase in α-tocopherol tissue levels (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001) in meat from animals fed flaxseed and increased dietary vitamin E resulted in the lowest drip loss values (P=0.013). As expected, display time had a large effect on retail traits in both steaks and patties (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). While retail traits of steaks were not affected by the dietary treatments (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;0.05), feeding flaxseed decreased (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.05) ground beef retail scores, which were not corrected by higher levels of dietary vitamin E. Finally, although no effect (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;0.05) was observed among treatments for sensory attributes in steaks, the correlations of a combined n-3:α-tocopherol ratio against retail and sensory attributes (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.05) suggest that increased n-3 fatty acids levels require increased dietary antioxidants, such as vitamin E to avoid negative effects on meat quality from a loss in oxidative stability.
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