Huhtanen, P., Hetta, M. and Swensson, C. 2011. Evaluation of canola meal as a protein supplement for dairy cows: A review and a meta-analysis. Can. J. Anim. Sci. 91: 529-543. A review and a meta-analysis were conducted to compare the feeding value of soybean meal (SBM) and canola meal (CM) in dairy cows and to evaluate the effects of heat-treatment of CM (TCM) on the performance of dairy cows. The dataset included in total 292 treatment means from 122 studies, in which dietary crude protein (CP) concentration was increased by replacing energy supplements with protein supplements. A mixed model regression analysis with random study effect was used to estimate the marginal production responses to different protein sources. The differences between the slopes were compared by t-test. All protein sources increased dry matter intake, but the responses were greater (P<0.01) for CM and TCM compared with SBM. Feeding CM or TCM produced greater (P<0.01) daily milk yield responses than SBM (3.4±0.19 and 3.7±0.25 vs. 2.1±0.25) kg kg^-1 increase in CP intake. Marginal milk protein yield responses (g kg^-1 increase in CP intake) were greater (P<0.01) for CM (136±5.4) and TCM (133±8.5) compared with SBM (98±8.0). Smaller response to incremental CP intake can partly be related to the higher average dietary CP concentration in SBM studies. Literature data on rumen ammonia N concentration and omasal protein flow did not support the higher ruminal tabulated ruminal CP degradability of CM compared with SBM. It is concluded that CM can successfully be substituted for SBM on isonitrogenous basis and that most feed evaluation systems overestimate metabolizable protein concentration of SBM relative to CM.

Dugan, M. E. R., Aldai, N., Aalhus, J. L., Rolland, D. C. and Kramer, J. K. G. 2011. Review:rans-forming beef to provide healthier fatty acid profiles. Can. J. Anim. Sci. 91: 545-556.Trans fatty acids are found naturally in foods, particularly in those derived from ruminant animals, such as beef and dairy cattle. Over the past few decades, human consumption of trans fatty acids has increased, but this has been mainly from products containing partially hydrogenated vegetable oils. The correlation of trans fatty acid consumption with diseases such as coronary heart disease has been cause for concern, and led to recommendations to reduce their consumption. Trans fatty acids, however, have differing effects on human health. Therefore, in foods produced from ruminant animals, it is important to know their trans fatty acid composition, and how to enrich or deplete fatty acids that have positive or negative health effects. This review will cover the analysis of trans fatty acids in beef, their origin, how to manipulate their concentrations, and give a brief overview of their health effects.

Sebastian, T., Watts, J. M., Stookey, J. M., Buchanan, F. and Waldner, C. 2011. Temperament in beef cattle: methods of measurement and their relationship to production. Can. J. Anim. Sci. 91: 557-565. Temperament is an individual trait influencing an animal's behavioural response to handling. This characteristic likely modulates the response of the animal to environments and social situations, and is perhaps best viewed as a component of its personality. We assessed temperament using three objective measuring tools, to determine if correlations exist between these and a traditional subjective evaluation. The tools used were strain gauges, a “movement measuring device” (MMD), and a chute exit timer. Four hundred steers were used. Exit time was correlated with values recorded with the MMD and absolute strain forces, and MMD values were related to absolute strain forces. When the animals were classified as “calm” or “wild” based on their subjective scoring, these two groups differed in their mean exit times, MMD values and absolute strain forces. The three objective measures yielded statistically correlated results between tests and across repetitions, and therefore may quantify correlated aspects of a personality trait (i.e., temperament). The objective scores were related to the traditional subjective score, but they provide the advantage of eliminating observer bias and may offer better tools for temperament selection. Significant positive relationships of daily gain with subjective score and MMD values indicate that traditional subjective scoring techniques can be replaced with more repeatable objective measures when temperaments are assessed for performance studies.

Pugh, K. A., Stookey, J. M. and Buchanan, F. C. 2011. An evaluation of corticotropin-releasing hormone and leptin SNPs relative to cattle behaviour. Can. J. Anim. Sci. 91: 562-572. The purpose of this study was to identify associations between single nucleotide polymorphisms (SNPs) in two genes involved in the hypothalamic-pituitary-adrenal axis and growth, namely corticotropin-releasing hormone (CRH), and leptin (LEP), and measurements of temperament in beef cattle. Four hundred crossbred beef steers were evaluated upon entry into a beef facility using several different measurements of response to handling: subjective score (SS), strain gauge (SG), movement measurement device (MMD) and exit time (ET). The steers were genotyped at the CRH 22C>G, CRH 240C>G and LEP 73C>T SNPs by PCR-RFLP. The SNP genotypes and two-way interactions between LEP and each CRH SNP were analyzed as effects on the various temperament measurements. We found interactions between CRH 22C>G and LEP and CRH 240C>G and LEP with SG. Within this interaction there appears to be a positive effect of one CRH allele (C) within LEP TT animals while in LEP CC the other CRH allele (G) had a positive effect. These interactions, especially between CRH 22C>G and LEP, needs to be confirmed in other populations of beef cattle. It may be possible in the future to select for temperament alongside production goals.

Basarab, J. A., Colazo, M. G., Ambrose, D. J., Novak, S., McCartney, D. and Baron, V. S. 2011. Residual feed intake adjusted for backfat thickness and feeding frequency is independent of fertility in beef heifers. Can. J. Anim. Sci. 91: 573-584. This study examined the effects of residual feed intake (RFI), RFI adjusted for off-test backfat thickness (RFI_fat) and RFI adjusted for off-test backfat thickness and feeding event frequency (RFI_{fat & activity}) on heifer fertility and productivity. Beef heifers (n=190) were monitored for individual daily feed intake and feeding event activity over 108-112 d using the GrowSafe System® and assessed for age at puberty based on plasma progesterone concentration. Individual animal daily feed intake, feeding event activity and off-test backfat thickness were then used to calculate RFI, RFI_fat and RFI_{fat & activity} and group heifers as either negative ([-], RFI<0.0) or positive ([ ], RFI≥0.0) for RFI. Heifers averaged 298 kg (SD=34) in body weight, were 276 days of age (SD=19) at the start of test, grew at 0.90 kg d^-1 (SD=0.21), consumed 7.62 kg DM head^-1 d^-1 (SD=0.84) and had a feed conversion ratio of 8.93 (SD=2.43). Age (351 d, SD=43) and weight (367.3 kg, SD=45.0) at puberty were similar between [-] and [ ] RFI heifers, but age at puberty was delayed in [-] RFI_fat (P=0.04) and RFI_{fat & activity} (P=0.08) heifers compared with [ ] RFI_fat and RFI_{fat & activity} heifers. Efficient or [-] RFI heifer exhibited a lower pregnancy (76.84 vs. 86.32%, P=0.09) and calving rate (72.63 vs. 84.21%, P=0.05) compared with [ ] RFI heifers. These differences were partially removed in [-] RFI_fat and completely removed in [-] RFI_{fat & activity} compared with their [ ] RFI counterparts (pregnancy rate, 80.85 vs. 82.29%, P=0.80; calving rate, 75.53 vs. 81.25%, P=0.34). No differences were observed between efficient and inefficient heifers in calving difficulty, average calving date, age at first calving, calf birth weight, calf pre-weaning ADG, calf weaning weight and heifer productivity. However, [ ] RFI heifers exhibited a 1.9-fold higher calf death loss compared with [-] RFI heifers (11.11% vs. 5.71%, P=0.24). This difference was more pronounced in [ ] RFI_fat and [ ] RFI_{fat & activity} heifers, which exhibited 2.2-fold (11.84% vs. 5.33%, P=0.15) and 3.0-fold (12.66% vs. 4.17%, P=0.06) higher calf death loss compared with [-] RFI heifers. There was no relationship of RFI adjusted for backfat thickness and feeding activity on fertility traits indicating that backfat thickness and feeding activity may be associated with feed intake and should be considered when selecting heifers for improved feed efficiency.

de la Fuente, L. F., Gonzalo, C., Sánchez, J. P., Rodríguez, R., Carriedo, J. A. and San Primitivo, F. 2011. Genetic parameters of the linear body conformation traits and genetic correlations with udder traits, milk yield and composition, and somatic cell count in dairy ewes. Can. J. Anim. Sci. 91: 585-591. This study was designed to estimate the inheritance of linear body conformation traits and their genetic correlations with linear udder traits, milk yield and composition, and somatic cell count (SCC) in dairy sheep. A total of 10 189 records of five body conformation traits, five linear udder traits, milk yield, protein and fat content, and SCC were obtained from 3977 adult ewes that were daughters of 268 sires belonging to 23 commercial flocks enrolled in the Churra breed selection nucleus. All type traits were scored on a nine-point linear scale. Genetic correlations and heritabilities were estimated using a repeatability multitrait animal model. Body conformation (stature, rear leg-rear view, feet angle, rump width, and general body score) had heritabilities (0.19, 0.18, 0.24, 0.14 and 0.17) and repeatabilities (0.34, 0.42, 0.42, 0.36, and 0.35), which indicate good potential for selection. For udder traits (udder depth, udder attachment, teat placement, teat length and udder shape) heritabilities varied between 0.09 and 0.26, and repeatabilities between 0.35 and 0.53. General body score (composite trait) had high phenotypic and genetic correlations with rear leg-rear view (0.64 and 0.80) and rump width (0.42 and 0.58). The phenotypic and genetic correlation between general body score and udder shape (composite trait) was 0.23 and 0.44, respectively. In addition, phenotypic and genetic correlations between body conformation traits and milk yield, protein and fat percentages, and SCC were low in most cases; therefore, no significant correlated genetic response is expected in body conformation traits when selecting for milk yield, protein and fat percentages, and SCC variables, in Churra breed. In conclusion, the heritability and repeatability values found in this study for body conformation traits, combined with the ease of recording by linear scale, make improvement by selection possible in dairy sheep.

He, J., Lu, L., Tian, Y., Tao, Z., Wang, D., Li, J., Li, G., Shen, J., Fu, Y. and Niu, D. 2011. Short Communication: Analysis of intramuscular fat and fatty acids of different duck breeds and their association with SNPs of duckA-FABPgene. Can. J. Anim. Sci. 91: 593-596. Intramuscular fat (IMF) is related to organoleptic characteristics of meat. Adipocyte fatty acid-binding protein (A-FABP) is one of the intracellular lipid-binding proteins involved in the transportation of fatty acids. The IMF contents of six duck breeds were measured, and the complete sequence and part of the 5' flanking region of duck A-FABP gene were obtained in this study. The IMF contents of different breeds were significantly different (P<0.05). Two SNPs were detected in the exon 3, one (HQ640428: g.2018A>G) was significantly associated with the contents of three fatty acids, total IMF and pectoral muscle weight. This work provides useful data for duck breeding.

Sharma, B. S., Verschoor, C. P. and Karrow, N. A. 2011. Short communication:Associations ofBoLAallelesDRB3.2*16andDRB3.2*23with health-related traits in Holstein bulls. Can. J. Anim. Sci. 91: 597-600. The relationships between bovine leukocyte antigen (BoLA) DRB3.2 alleles and health and fertility traits were investigated. A group of 548 Canadian and American Holstein bulls was genotyped for the presence of DRB3.2*16 and DRB3.2*23 alleles using the multi-primer target polymerase chain reaction technique. The traits of interest included somatic cell score (SCS), lactation persistency, daughter fertility (DF), and herd life (HL). Higher frequencies were observed for alleles DRB3.2*16 and DRB3.2*23 in this bull population compared with previous reports. In a comparison-wise level, some significant contrasts were detected; however, no association was detected between the DRB3.2 alleles and SCS. Allele DRB3.2*16 had a favorable effect on HL compared with allele DRB3.2*23. On the other hand, these two alleles had a favorable influence on DF, additionally, individuals carrying both of these two alleles performed better than the individuals carrying either allele. Further investigation is warranted to examine the effects of these alleles on HL and reproduction performance.

Meadus, W. J., Duff, P., Rolland, D., Aalhus, J. L., Uttaro, B., and Dugan, M. E. R. 2011. Feeding docosahexaenoic acid to pigs reduces triglycerides in blood and induces gene expression for fat oxidation in liver and adipose but not in muscle. Can. J. Anim. Sci. 91: 601-612. The essential fatty acids required in diets of humans are linoleic acid (18:2n-6:LA) and α-linolenic acid (18:3n-3: ALA), and these can be elongated and desaturated to form long-chain omega-6 or omega-3, respectively. Even though not considered essential, consumption of long-chain omega-3 fatty acid is recommended for health benefits, including protection against cardiovascular disease. The omega-3 fatty acid, docosahexanoic acid (DHA), was supplemented in pig diets as a dried biomass of the microalgae Schizochytrium to see if there are unique physiological changes associated with DHA feeding. Pigs were fed a diet with 330 mg (low), 3600 mg (medium) or 9400 mg (high) DHA per day for the last 25 d before slaughter at market weight (~110 kg). Blood triglycerides (TG) were assayed colormetrically and tissue samples were analyzed for gene expression patterns of RNA by quantitative real-time polymerase chain reaction. Fatty acids were analyzed by gas chromatography. Animal performance appeared to increase with DHA, as shown by a 14% improved feed:gain ratio of 2.74±0.27 (P<0.05). Blood triglycerides were reduced significantly from 0.40±0.23 mM to 0.20±0.09 mM. Pigs accumulated 14 times more DHA in their subcutaneous fat (SQ) (10.67 mg g^-1) on the high diet compared with the control diet (0.75 mg g^-1). Gene analysis showed that the expression of the fat oxidation biomarkers acyl CoA oxidase 1 (ACOX1), peroxisome proliferator-activated receptors alpha (PPARα) and gamma (PPARγ) were stimulated in the SQ and liver. The delta-6 desaturase (D6D) and elongase (Elov5), which are genes involved in the endogenous synthesis of DHA, were unchanged. Fatty acid synthase (FASN) was stimulated in the liver and muscle of pigs on the high DHA diet. Analysis of gene transcription activity suggested fat metabolism was stimulated in the liver and SQ fat, but the genes involved in the endogenous production of DHA remained unchanged.

Hernández-Calva, L. M., He, M., Juárez, M., Aalhus, J. L., Dugan, M. E. R. and McAllister, T. A. 2011. Effect of flaxseed and forage type on carcass and meat quality of finishing cull cows. Can. J. Anim. Sci. 91: 613-622. Sixty-two cull cows were fed one of four diets in a 2×2 factorial arrangement, consisting of barley silage or grass hay with or without flaxseed to influence fatty acid composition. After slaughter, carcass grade, meat quality and sensory data were collected. Silage increased live (P=0.002) and carcass (P=0.001) weights of the cows as compared with hay. Muscle width (P=0.013) and score (P=0.010) and rib-eye area (P=0.002) were enhanced when silage was included in the diet, whereas supplementation with flaxseed increased (P=0.003) grade fat depth by 29%. Most subjective and objective retail evaluation traits in steaks from the left longissimus thoracis and ground meat were negatively affected (P<0.05) by the length of the retail display time. Moreover, dietary hay increased (P=0.015) the lean colour values in steaks and ground beef, which was corroborated by lower L* (P=0.009) and higher hue (P=0.010) in steaks and lower L* (P=0.049), chroma (P=0.005) in ground beef as compared with cows fed silage. A significant interaction between forage type and flax inclusion for thiobarbituric acid reactive substances (TBARS) (P=0.050) was observed. After sensory evaluation, steaks from cows fed silage had an increase (P=0.030) in beef flavour intensity when compared with cows fed hay, whereas inclusion of flaxseed in the diet decreased (P<0.001) beef flavour intensity in steaks from cows fed both forage sources. Sensory evaluation of ground beef found that hay-fed cows with flaxseed supplementation had decreased (P=0.03) beef flavour intensity, while the same effect was not observed in ground beef from cows fed silage with flaxseed. Results from this study show that inclusion of flaxseed in the diet reduced off-flavours in steak, but for ground beef this response depended on the source of forage in the diet.

Juárez, M., Dugan, M. E. R., Larsen, I. L., Thacker, R., Rolland, D. C. and Aalhus, J. L. 2011. Oxidative stability in grinds from omega-3 enhanced pork. Can. J. Anim. Sci. 91: 623-634. In order to investigate the effect of enhancing n-3 fatty acid levels in carcasses on the retail and sensory characteristics of pork grinds, as well as the ability of increasing dietary levels of vitamin E to stabilize the increase in PUFA levels from flaxseed supplementation, 81 pigs were used in a 3×3 factorial experiment. Dietary treatments included three lengths of time (0, 3 and 6 wk) of flaxseed supplementation and three levels of vitamin E (40, 200 and 400 mg kg feed^-1). α-Tocopherol tissue levels increased with dietary vitamin E supplementation (P<0.001), and fat softness (P=0.018) and total PUFA and n-3 fatty acids (P<0.001) increased with flaxseed supplementation. Most other animal performance, carcass and lean pork quality traits were not affected (P>0.05) by dietary treatments. In ground pork, the increase in TBARS after 6 d in retail was lower (P<0.001) with increasing dietary vitamin E levels. However, vitamin E had no effect (P>0.05) on the higher (P<0.001) TBARS levels observed in grinds from flaxseed fed pigs. The dietary addition of flaxseed negatively modified (P<0.05) all the sensory attributes of both cooked and reheated products. Increasing the fat content of the grinds up to 30% seemed to counteract (P>0.05) the negative effects of feeding flaxseed for 3 wk. Feeding vitamin E was not able to prevent negative effects (P<0.05) observed during retail display in grinds with either increasing fat content or higher n-3 fatty acids from dietary flaxseed. However, increasing dietary vitamin E only showed a protective effect (P<0.05) on retail appearance after long periods of ageing.

Girard, I., Aalhus, J. L., Basarab, J. A., Larsen, I. L. and Bruce, H. L. 2011. Modification of muscle inherent properties through age at slaughter, growth promotants and breed crosses. Can. J. Anim. Sci. 91: 635-648. A 2⁴ factorial experiment tested the interactions of slaughter age (12-13 or 18-20 mo), growth hormone use, ß-adrenergic agonist (ß-AA) use and breed cross [Hereford-Aberdeen Angus (HAA) or Charolais-Red Angus (CRA)] on the composition, fibre types, and connective tissue characteristics of m. semitendinosus (ST) and m. gluteus medius (GM) from 112 crossbred steers. Muscle weights increased with slaughter age, implantation and CRA genetics (P<0.05), but were not affected by ractopamine hydrochloride (RAC) (P>0.10).Animal age increased fast glycolytic (FG) and decreased fast oxidative glycolytic (FOG) fibre percentages by 7.2 and 6.6%, respectively, in the ST and increased slow oxidative (SO) and FOG fibre areas in both muscles (P<0.05). Cross-sectional areas of all fibre types were increased in the ST with implantation. In the GM, implantation increased SO (3.1%) and reduced FOG (3.2%) fibre percentages, while RAC reduced the SO (3.8%) and increased the FG (6.1%) fibre percentages (P<0.05).Only GM total collagen content increased with slaughter age (P<0.05),but collagen solubility decreased with slaughter age for both muscles (P<0.05). CRA genetics increased FG percentage in the GM of yearling-fed steers and increased moisture and protein and reduced fat contents of both muscles (P<0.05). In the muscles studied, IMP, slaughter age and animal genetics induced greater changes in muscle inherent properties than RAC.

Sheppard, S. C., Bittman, S., Swift, M. L. and Tait, J. 2011. Modelling monthly NH₃emissions from dairy in 12 Ecoregions of Canada. Can. J. Anim. Sci. 91: 649-661. Ammonia (NH₃) from livestock manure is emitted from barns, storages and manured land, and is a loss to the farm operations, while atmospheric NH₃ has potential impacts beyond the farm, including human health and ecological damage. Models are used to estimate the intensity and spatial extent of NH₃ emissions, and this paper reports a recent model developed for quantifying emissions from the dairy sector in Canada. The estimated overall average emission to the atmosphere in Canada in 2006 was 42.4±9.0 kg NH₃ cow^-1 yr^-1 from a lactating cow, and total emission from the Canadian dairy sector was 56000 t NH₃. On many farms the NH₃ emissions may have been a significant portion of the N requirements of their crops. The emission estimates in the 12 Ecoregions were proportional to the animal census. Emissions generally peaked in May, mainly because of landspreading of manure. There were also differences in emissions per animal among the Ecoregions related to the specific practices, such as amount of grazing and injection of slurry. The sensitivity analysis suggested that a shift from the present 14% injection of slurry manure into soil to 80% may be effective overall, potentially decreasing annual emissions by 13% and emissions in May by 27%.

Soares, J. A., Singh, V., Stein, H. H., Srinavasan, R. and Pettigrew, J. E. 2011. SHORT COMMUNICATION: Enhanced distillers dried grains with solubles (DDGS) has greater concentration of digestible and metabolizable energy than DDGS when fed to growing and finishing pigs. Can. J. Anim. Sci. 91: 663-667. To better use distillers dried grains with solubles (DDGS) for non-ruminants, some of the fiber may be removed. The “elusieve” process removes approximately 10% of DDGS material, mostly fiber, yielding enhanced DDGS (E-DDGS). An experiment was conducted to compare the DE and ME in E-DDGS to those in DDGS when fed to growing and finishing pigs. Overall, E-DDGS has greater DE, ME and ME_n than DDGS.

Gibb, D. J., Van Herk, F. H., Mir, P. S., Loerch, S. and McAllister, T. A. 2011. Removal of supplemental vitamin A from barley-based diets improves marbling in feedlot heifers. Can. J. Anim. Sci. 91: 669-674. The objective of this research was to determine if removing supplemental vitamin A from barley-based feedlot diets affects animal performance, health, or carcass quality. Six pens per treatment (10 heifers per pen) were randomly assigned to receive zero (-VA) or 3640 ( VA) IU kg^-1 dry matter of supplemental vitamin A in barley-based feedlot diets. Initial serum retinol was similar between treatments (28 µg dL^-1; P=0.34), but -VA reduced levels by 40% (30 vs. 50 µg dL^-1; P<0.001) by day 217. Removal of supplemental vitamin A reduced dry matter intake during the 58 d backgrounding period (6.93 vs. 7.07 kg d^-1; P=0.007) and over the 218-d trial (9.18 vs. 9.35 kg d^-1; P<0.001), but had no effect on average daily gain during backgrounding (1.22 kg d^-1; P=0.46) or over all (1.46 kg d^-1; P=0.15). Based on camera grading, -VA increased degree of marbling (480.6 vs. 439.3; P=0.02) without affecting backfat thickness (0.74 cm; P=0.62). Ultrasound measurements were highly correlated with camera grading, but did not detect treatment difference in marbling score (P=0.99). Results from this study show that the removal of supplemental vitamin A increased marbling without affecting backfat, gains, or animal health.

Zoffoun, A. G., Babatounde,S., Houinato, M., Mensah, G. A. and Sinsin, B. 2011. Eating behavior of the Girolando cattle on two types of cultivated pastures in the subequatorial zone. Can. J. Anim. Sci. 91: 675-683. The eating behavior of the Girolando dairy cattle on the artificial grazing pastures of Panicum maximum and Panicum maximum var. C1 was studied in the subequatorial zone of Benin. Sixteen young male cattle were distributed into two groups of eight animals each. Group 1 was fed on Panicum maximum and group 2 on Panicum maximum var. C1. The animals were followed with direct observation of the different grazing activities according to the hand-plucking method.Animals fed Panicum maximum spent 66.7% of the time grazing, 9.9%in rumination, 18.1% resting, and 5.3% watering; those fed Panicum maximum var. C1 spent 54.3% of the time grazing, 12.0% in rumination, 28.4% resting and 5.3% watering. The most elevated values of voluntary ingestion were obtained on Panicum maximum pasture. On average, animals on Panicum maximum var. C1 pasture ingested significantly (P< 0.05) more (109.39 compared with 69.67 g DM kg LW^-0.75 d^-1).These are fundamental data for the implementation of alimentation plans for Girolando cattle.

Arya, S. and McKinnon, J. J. 2011. The effects of a low lignin hull, high oil groat oat on the performance and carcass characteristics of feedlot cattle. Can. J. Anim. Sci. 91: 685-693. A study was conducted to evaluate inclusion levels of a low lignin hull, high oil groat oat (CDC SO-I) on the performance and carcass characteristics of feedlot cattle. Two hundred crossbred steers (average weight of 427.3 kg±22.4) fed in 20 pens (10 head per pen) were used. Five treatments, formulated by replacing barley grain with increasing levels of CDC SO-I oat (Barley grain:CDC SO-I oat ratios of 100:0; 75:25; 50:50; 25:75 and 0:100; DM basis) were used. Over the entire study, there was a linear decrease (P<0.01) in DMI and ADG with increasing inclusion level of CDC SO-I oat. There was a quadratic effect (P=0.03) on gain to feed with similar values for steers fed 100:0, 75:25, 50:50 and 75:25 and then decreasing for the 0:100 treatment. Days on feed increased (P=0.03) quadratically with steers fed the 75:25 and 0:100 treatments spending the longest time on feed. Increasing the inclusion level of CDC SO-I oat in the diet also linearly decreased (P<0.01) carcass weight, dressing percentage and carcass grade fat. However, there was no effect of treatment on l. dorsi area and lean meat yield. There was no effect (P>0.05) of treatment on marbling score. Overall, the results of this study indicate that replacement of barley grain by CDC SO-I oat in finishing diets decreases DMI and as a result leads to reduced ADG, increased days on feed and lower slaughter and carcass weights.

Ramirez-Bribiesca, J. E., Wang, Y., Jin, L., Canam, T., Town, J. R., Tsang, A., Dumonceaux, T. J. and McAllister, T. A. 2011. Chemical characterization and in vitro fermentation ofBrassicastraw treated with the aerobic fungus,Trametes versicolor. Can. J. Anim. Sci. 91: 695-702. Brassica napus straw (BNS) was either not treated or was treated with two strains of Trametes versicolor; 52J (wild type) or m4D (a cellobiose dehydrogenase-deficient mutant) with four treatments: (i) untreated control (C-BNS), (ii) 52J (B-52J), (iii) m4D (B-m4D) or (iv) m4D glucose (B-m4Dg). Glucose was provided to encourage growth of the mutant strain. All treatments with T. versicolor decreased (P<0.05) neutral-detergent fibre and increased (P<0.05) protein and the concentration of lignin degradation products in straw. Ergosterol was highest (P<0.05) in straw treated with B-52J, suggesting it generated the most fungal biomass. Insoluble lignin was reduced (P<0.05) in straw treated with B-52J and B-m4D, but not with B-m4Dg. Mannose and xylose concentration were generally higher (P<0.05) in straw treated with fungi, whereas glucose and galactose were lower as compared with C-BNS. The four treatments above were subsequently assessed in rumen in vitro fermentations, along with BNS treated with 2 mL g^-1 of 5 N NaOH. Concentrations of total volatile fatty acids after 24 and 48h were lower (P<0.05) in incubations that contained BNS treated with T. versicolor as compared with C-BNSor NaOH-treated BNS. Compared with C-BNS, in vitrodry matter disappearance and gas production were increased (P<0.05) by NaOH, but not by treatment with either strain of T. versicolor. Although treatment with T. versicolor did release more lignin degradation products, it did not appear to provide more degradable carbohydrate to in vitro rumen microbial populations, even when a mutant strain with compromised carbohydrate metabolism was utilized. Production of secondary compounds by the aerobic fungi may inhibit rumen microbial fermentation.

Holtshausen, L., Beauchemin, K. A., Schwartzkopf-Genswein, K. S., González, L. A., McAllister, T. A. and Gibb, D. J. 2011. Performance, feeding behaviour and rumen pH profile of beef cattle fed corn silage in combination with barley grain, corn or wheat distillers' grain or wheat middlings. Can. J. Anim. Sci. 91: 703-710. This study compared growth performance, feeding behaviour and ruminal pH profile of growing beef heifers fed a total mixed ration (TMR) containing corn silage and either [400 g kg^-1 dry matter (DM)] barley grain (CTL), corn dried distillers' grain with solubles (CDDGS), wheat dried distillers' grain with solubles (WDDGS) or wheat middlings (WM). Eighty beef heifers (16 ruminally cannulated; 301±34 kg) were blocked by weight and randomly assigned to eight feedlot pens for a 70-d backgrounding study. Pens were randomly assigned to one of four dietary treatments and equipped with the GrowSafe feed intake system for determining individual feed intake and monitoring feeding behaviour. Dry matter intake (DMI) was lower (P<0.01) and average daily gain (ADG) tended to be lower for CTL (P=0.06) heifers as compared with heifers on other treatments. Feed conversion efficiency (i.e., gain to feed ratio; P=0.41) and feeding behaviour and ruminal pH profile measurements (P>0.05) did not differ among treatments. This study illustrates that barley grain can be replaced by corn dried distillers' grain, wheat dried distillers' grain or wheat middlings in diets fed to growing beef cattle without compromising feed conversion efficiency, adversely affecting feeding behaviour (e.g., decreased meal frequency and duration) or increasing the incidence of ruminal acidosis.

Turner, T., Rolland, D. C., Aldai, N. and Dugan, M. E. R. 2011. Short Communication: Rapid separation ofcis9,trans11- andtrans7,cis9-18:2 (CLA) isomers from ruminant tissue using a 30 m SLB-IL111 ionic column. Can. J. Anim. Sci. 91: 711-713. Rumenic acid (cis9,trans11-18:2) is the main natural isomer of conjugated linoleic acid (CLA). Rumenic acid has many purported health benefits, but effects of most other CLA isomers are unknown. Typically trans7,cis9-18:2 is the second most abundant CLA isomer, but it co-elutes with rumenic acid on conventional polar gas chromatography (GC) columns, requiring complimentary analysis with silver-ion high performance liquid chromatography (Ag -HPLC). Herein we report a rapid method for analyzing rumenic acid and trans7,cis9-18:2 using a 30 m ionic-liquid GC column. Optimal resolution of the two CLA isomers was at 145°C and analysis of backfat from barley-fed cattle compared well with GC/Ag -HPLC (y=0.978x - 0.031, r=0.985, P<0.001).