Barley Silage Research Articles

Bioperformance evaluation of various summer pasture and winter feeding strategies for cow-calf production

Legesse, G., Small, J. A., Scott, S. L., Kebreab, E., Crow, G. H., Block, H. C., Robins, C. D., Khakbazan, M. and McCaughey, W. P. 2012. Bioperformance evaluation of various summer pasture and winter feeding strategies for cow-calf production. Can. J. Anim. Sci. 92: 89–102. Bioperformance of two summer pasture and four winter feeding cow-calf production strategies in the western Canadian Parkland was evaluated. Diet composition and animal data were collected over 5 production years. Each production year began with fixed-time artificial insemination (TAI) of cows and turnout of cow-calf pairs (n=288 yr−1 including 76 primiparous replacement cows) assigned to either alfalfa-grass (AG, n=9 paddocks) or grass (G, n=9 paddocks) pastures until weaning. Post-weaning, pregnant cows (n=240 yr−1) were assigned to either extended-grazing (EG, n=120) of dormant regrowth of perennial pastures and swathed annual crops, or one of three diets fed in a drylot (DL): hay (HY, n=40), straw/barley (SB, n=40; 70% oat straw:30% steam-rolled barley grain DM), and silage/straw (SS, n=40; 40% barley silage:60% oat straw DM). Common diets were used for all treatment groups between the weaning and winter feeding period, as well as between the pre-calving and summer grazing period. Cow and calf body weight (BW) gains were higher (P<0.05) for AG than G pasture until the third production year and the advantage diminished as the carrying capacity declined. The latter may be attributed to a lack of spring/summer moisture. Further, G pastures required more nitrogen fertilizer to achieve the same level of bioperformance as that of AG pastures in years 4 and 5. Cows in the EG treatment maintained BW better than those in the DL treatment (especially those cows receiving the SS diet) except in year 5 (P<0.05) in which drought resulted in lower body weights for cows in the EG treatment. On all treatments, cows maintained BCS that supported reproductive function; however, fertility to TAI was lowest (P<0.05) in years 4 and 5. Cows in the DL group had a 1.8 times greater risk of being culled before turnout and as a result lower (P<0.05) rates of calf survival to weaning. In conclusion, AG pastures and EG are important alternatives to further develop for cow-calf production in western Canada.

Feeding flaxseed in grass hay and barley silage diets to beef cows increases alpha-linolenic acid and its biohydrogenation intermediates in subcutaneous fat1

The objective of the study was to determine temporal fat deposition and fatty acid profiles in beef cows fed hay- or barley silage-based diets, with or without flaxseed. Crossbred cull beef cows (n = 64, >30 mo of age, 620 ± 5 kg) were removed from grassland pastures, randomly assigned to 16 pens, and given ad libitum access to 50:50 (wt/wt, DM basis) forage:concentrate diets containing 0 or 15% ground flaxseed (DM basis, 5.2% added fat). Diets consisted of hay control (HC), hay+flaxseed (HF), barley silage control (SC), and silage+flaxseed (SF). Backfat biopsies were obtained from each cow at 0, 6, and 12 wk, and at slaughter (~20 wk) to assess fatty acid composition. With the exception of feed efficiency, flaxseed × forage interactions were not significant for backfat accumulation or performance parameters. Flaxseed improved (P < 0.01) feed conversion when supplemented to hay-based diet and increased ADG (P = 0.03), resulting in a heavier (P = 0.02) BW. Compared with hay, barley silage increased (P < 0.01) DMI, ADG, and feed efficiency. Subcutaneous fat contained 0.68% n-3 fatty acids at wk 0, and reached 0.68, 0.81, and 0.94% in HF cows after 6, 12, and 20 wk, respectively (Y(n-3) = 0.0133X + 0.6491, r = 0.87). It was 0.67% at wk 0, and reached 0.65, 0.77, and 0.90% in SF cows after 6, 12, and 20 wk, respectively (Y(n-3) = 0.0121X + 0.6349, r = 0.75). In contrast, weight percentage of n-3 fatty acids decreased in HC cows from 0.63, 0.50, and 0.47, to 0.43%, and in SC cows from 0.63, 0.40, and 0.36, to 0.33% over the 20 wk. A forage × flaxseed interaction (P < 0.05) occurred for many of the α-linolenic acid (ALA) biohydrogenation intermediates, including vaccenic acid (C18:1 trans-11) and CLA (combined C18:2 trans-7,cis-9 and cis-9,trans-11) in plasma, and in subcutaneous fat this also included non-CLA dienes. Concentrations of most α-linolenic acid biohydrogenation intermediates were greater when feeding flaxseed with hay. In conclusion, forage source altered plasma concentrations and rate of accumulation of ALA biohydrogenation products in subcutaneous fat from beef cows fed flaxseed. Factors responsible for this response are yet to be defined, but may include forage-mediated changes in ruminal biohydrogenation of ALA, as well as alterations in fatty acid metabolism and deposition.

Influence of α-tocopherol supplementation on trans-18:1 and conjugated linoleic acid profiles in beef from steers fed a barley-based diet

The current study was conducted to determine the effect of different α-tocopherol (vitamin E) inclusion levels on trans(t)-18:1 and conjugated linoleic acid (CLA) profiles in subcutaneous and intramuscular fat of steers fed a barley-based diet. Fifty-six feedlot steers were offered a barley-based finisher diet (73% steam rolled barley, 22% barley silage and 5% supplement as-fed basis) with four levels of supplementary dl-α-tocopheryl acetate (340, 690, 1040 or 1740 IU/steer per day) for 120 days. Adding vitamin E to the diet had little effect on the overall fatty acid composition of intramuscular fat. The proportion of individual and total t,t- and cis(c),t-CLA, n-3 fatty acids, total polyunsaturated fatty acids (PUFA), mono-unsaturated fatty acids and saturated fatty acids to PUFA ratio in subcutaneous fat were not influenced (P > 0.05) by dietary vitamin E supplementation. Increasing levels of vitamin E led to linear reductions in t6-/t7-/t8-18:1 and t10-18:1 (P < 0.05), and linear increase in t11-/t10-18:1 ratio (P < 0.05) in subcutaneous fat. The content of 20:3n-6 and total n-6 in subcutaneous fat decreased (P < 0.05) linearly with increasing amounts of vitamin E. The subcutaneous fat n-6:n-3 ratio showed a quadratic (P < 0.05) response to vitamin E. In conclusion, although vitamin E supplementation has some potential to reduce t10-18:1 formation and increase t11-/t10-18:1 ratio in subcutaneous fat of cattle fed barley-based diets, the changes in the present study were limited and may not have been sufficient to impact on human health.

청보리사일리지 및 옥수수사일리지 급여가 육성기 재래 흑염소의 영양소 이용률, 성장 및 혈액성상에 미치는 영향

*ABSTRACTThis study examined the effects of feeding whole-crop barley silage(BS), corn silage(CS) and the mixture of BS and CS(CB) on feed consumption, daily gain, nutrients apparent digestibilities and blood parameters in order to investigate the feed evaluation in Korean black goats. BS, CS, and CB were fed to twelve Korean black goats, which were allocated into three groups in metabolic cages according to the latin-square design. As a result, dry and organic matter intakes for goats per day have shown a tendency to decrease in the order of CS, CB and BS, but there were no significant differences. We also found a similar tendency when the intakes of crude protein, crude fat, and non-fiber carbohydrates(NFC) were examined. However, ADF and NDF consumptions showed a decreasing tendency in the order of CB, BS and CS. Dry matter intakes per metabolic body weight showed the decreasing tendency in the order of CS (57.6g), CB(53.8g) and BS(52.7g), however with no statistical differences. Average daily gain of 64.2g in CB was significantly higher than the other groups(42.0g to 46.0g). Nitrogen intakes and nitrogen retention showed a decreasing tendency in the order of CS, CB and BC. Nevertheless, nitrogen retention in CS group was higher by 30% than that of the BC group with p<0.05. Apparant digestibilities of dry and organic matters were 72.6 and 72.8% for the CS group respectively, which were significantly higher than those of the BS group(67.5 and 69.0%) and the CB group(66.0 and 67.1%). In conclusion, the results of this study demonstrated that the CS group showed more positive feed consumption, digestibility, and nitrogen retention in Korean black goats than those of BS group. The CB group, however, showed similar results to the results of the CS group.(Key words: Whole-crop barley silage, Corn, Silage, Apparant digestibility, Growth performance, Nutrients intakes)

2010년산 맥류의 붉은곰팡이병 발생 및 Fusarium 곰팡이독소 자연발생

2010년산 쌀보리 43시료, 겉보리 17시료, 맥주보리 11시료, 청보리 14시료, 밀 41시료 등 총 126개 시료를 농가로부터 채집하였다. 이들 시료를 대상으로 Fusarium균 오염정도와 이들 균이 생산하는 주요 독소인 DON, NIV, ZEA의 자연발생을 조사하였다. 2010년산 맥류의 전국 평균 오염율은 23.0%로 2009년 전국 평균 오염율(Yeh 등, 2010)에 비해 10% 이상 높았다. 지역별 오염율은 전남지방의 맥류가 35.8%로 가장 높았고 전북 20.8%, 경기 20.5% 순이었다. 각 독소별 오염빈도와 오염수준을 조사한 결과, DON은 43시료(34%), 0.89 mg/kg 이었고, NIV는 107시료 (84.9%), 1.86 mg/kg, ZEA은 13시료(10.3%), 0.06 mg/kg이 었다. NIV의 오염빈도가 DON과 ZEA에 비해 높았다. 한편 40시료(31.7%)가 DON과 NIV가 중복오염되어 있었다. 맥류 종류별 곰팡이독소의 오염수준을 보면, 밀에서는 DON의 오염수준이 NIV보다 높았으며, 보리에서는 NIV 오염수준이 DON보다 높았다. 보리 종류별 NIV의 오염수준은 청보리, 맥주보리, 쌀보리, 겉보리 순으로 높았다. 독소오염에 대해 지역별로 분석하여보면 경기, 충남북의 중부지방은 DON의 오염수준이 NIV보다 높았으며, 전남북과 경남북의 남부지방은 NIV의 오염수준이 높았다. DON과 NIV 독소의 오염빈도 또한 중부지방에 비해 남부지방이 많았다. 지역별 맥류 곰팡이독소 자연발생 양상의 차이를 처음으로 보고한다. Fusarium species are worldwide causal agents of Fusarium head blight (FHB) in cereals such as barley and wheat. Their toxigenic potential is a health risk for both humans and animals. To survey the natural occurrence of FHB and mycotoxins produced by Fusarium, total 126 barley or wheat grains grown in 2009-2010 season in Korea were collected. The incidence of FHB was 30.7% in silage barley, 26.9% in wheat, 20.7% in naked barley, 19.4% in malting barley, 16.4% in unhulled barley. Overall FHB incidence of barley and wheat in 2010 was 23.0% and 10% higher than that of 2009. The incidences and level of deoxynivalenol (DON), nivalenol (NIV), and zearalenone (ZEA) were 34%, 0.89 mg/kg, 84.9%, 1.86 mg/kg, and 10.3%, 0.06 mg/kg respectively. The both levels and incidences of NIV were found to be highest in barley, whereas the level of DON was found to be highest in wheat. Incidences of DON and NIV and the level of NIV in the samples from southern regions of Korea were higher than those from central region, whereas the level of DON from central region was higher than that from southern regions. This is the first paper demonstrating regional difference in natural occurrence of DON and NIV in wheat and barley.

A third-generation esterase inoculant alters fermentation pattern and improves aerobic stability of barley silage and the efficiency of body weight gain of growing feedlot cattle1

This study investigated the effects of a mixed bacterial inoculant possessing ferulic acid esterase (FAE) activity on silage fermentation characteristics, aerobic stability, and growth performance of growing feedlot steers. Whole-crop barley (Hordeum vulgare L.) forage (35% DM) was chopped and ensiled without a silage inoculant (UN) or with a mixed bacterial culture containing 1.0 × 10(11) cfu/g of Lactobacillus buchneri LN4017 that produces FAE, 2.0 × 10(10) cfu/g of Lactobacillus plantarum LP7109, and 1.0 × 10(10) cfu/g of Lactobacillus casei LC3200 at a combined rate of 1.3 × 10(5) cfu/g of fresh forage (IN) in mini and Ag-Bag (Ag-Bag Int. Ltd., Warrenton, OR) silos. Silages from the mini silos were assessed for the effect of inoculation on fermentation characteristics and aerobic stability, whereas silages from Ag-Bags were used to formulate 2 barley silage-based total mixed rations (UN and IN) that were fed to growing feedlot steers for 112 d. The IN silage exhibited a homolactic fermentation during the first 7 d of ensiling as reflected by an increased (P ≤ 0.02) lactic acid concentration and an accelerated rate (P < 0.01) of pH decline. Thereafter, fermentation of IN silage became more heterolactic, resulting in greater concentrations of acetic acid (P < 0.01) and pH (P < 0.01) but less (P < 0.01) lactic acid than UN silage. Inoculation did not affect DM losses (P = 0.52) from mini silos. The IN silage remained stable during 21 d, but temperature and yeasts counts in the UN silage increased after 5 d of aerobic exposure. Growing steers fed the IN silage diet had superior (P = 0.03) feed conversion efficiency compared with those fed UN silage. Inoculation of whole-crop barley silage with a mixed culture of homolactic lactic acid-producing bacteria and FAE-producing L. buchneri at ensiling changed fermentation from a homolactic to a heterolactic form during ensiling and improved aerobic stability of the silage and efficiency of BW gain of growing feedlot steers.

Effect of flaxseed and forage type on carcass and meat quality of finishing cull cows

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&lt;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&lt;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.

Prediction of enteric methane output from milk fatty acid concentrations and rumen fermentation parameters in dairy cows fed sunflower, flax, or canola seeds

Milk fatty acid (FA) composition has been suggested as a means of predicting enteric methane (CH4) output in lactating dairy cattle because of the common biochemical pathways among CH4, acetate, and butyrate in the rumen. Sixteen lactating Holstein cows were used in a Latin square design with four 28-d periods. All diets contained steam-rolled barley, a pelleted supplement, barley silage [45% of dietary dry matter (DM)] and 3.3% added fat (DM basis) from 1 of 4 sources: calcium salts of long-chain FA (palm oil; control) or crushed oilseeds from sunflower, flax, or canola. The objectives of this study were to (1) compare the effect of diets on milk FA profile; (2) model CH4 production from milk FA composition, intake, and rumen fermentation variables; and (3) test the applicability of CH4 prediction equations reported in previous studies. Methane (g/d) was measured in chambers (2 animals/chamber) on 3 consecutive days (d 21–23). The test variables included total DM intake (DMI, kg/d; d 21–23), forage DMI (kg/d; d 21–23), milk yield (kg/d; d 21–23), milk components (d 18–21), milk FA composition (% total FA methyl esters; d 18–21), rumen volatile FA (mol/100mol; d 19–21), and protozoal counts (d 19–21), and were averaged by chamber and period to determine relationships between CH4 and the test variables. Milk trans(t)10-, t11-18:1, and cis(c)9t11-18:2 were greater for sunflower seeds compared with the other diets. Forage DMI (correlation coefficient, r=0.52; n=32), DMI (r=0.52; n=32), and rumen acetate + butyrate:propionate (r=0.72; n=16) were positively related to CH4 (g/d), whereas rumen propionate (r=0.63; n=16), milk c9-17:1 (r=0.64; n=32), and c11-18:1 (r=0.64; n=32) were negatively related to CH4. The best regression equation (coefficient of determination=0.90; n=16) was CH4 (g/d)=−910.8 (±156.7) × milk c9-17:1 + 331.2 (±88.8) × milk 16:0 iso + 0.0001 (±0.00) × total entodiniomorphs + 242.5 (±39.7). Removing rumen parameters from the model also resulted in a reasonably good estimate (coefficient of determination=0.83; n=32) of CH4. Stepwise regression analysis within diets resulted in greater coefficient of determination and lower standard error values. Predictions of CH4, using equations from previous studies for the data set from this study, resulted in a mean overestimation ranging from 19 to 61% across studies. Thus, milk FA alone may not be suitable for developing universal CH4 prediction equations.

Wheat distillers grains in feedlot cattle diets: Feeding behavior, growth performance, carcass characteristics, and blood metabolites1,2

A study was conducted to evaluate feed intake, ADG, carcass quality, eating behavior, and blood metabolites in feedlot beef steers fed diets that varied in proportion of wheat dried distillers grains with solubles (DDGS) replacing barley grain or barley silage. Two hundred crossbred steers (BW = 489 ± 30 kg) were blocked by BW and randomly allotted to 20 pens (5 pens per treatment). Steers were fed 1 of 4 diets: control without DDGS (CON), 25% (25DDGS), 30% (30DDGS), or 35% (35DDGS) wheat DDGS (DM basis). The CON diet consisted of 15% barley silage and 85% barley-based concentrate; the 3 wheat DDGS diets were formulated by substituting 20% barley grain and 5, 10, or 15% silage, respectively, with 25, 30, or 35% wheat DDGS so that the 35DDGS diet contained no silage. The diets were formulated such that wheat DDGS was substituted for both barley grain and barley silage to evaluate whether wheat DDGS can be fed as a source of both energy and fiber in feedlot finishing diets. Dry matter intake of steers fed 25DDGS was greater (P < 0.01), but final BW, ADG, and G:F were not different compared with steers fed CON diet. Carcass characteristics and liver abscess score were not different between CON and 25DDGS. Steers fed 25DDGS had longer eating time (min/d; P < 0.01), greater meal frequency (P < 0.04), but a slower eating rate (P < 0.04). Replacing barley silage with increasing amounts of wheat DDGS (from 25DDGS to 35DDGS) linearly reduced (P < 0.01) DMI. Final BW, ADG, and G:F were not affected by increasing amounts of wheat DDGS. Carcass traits were not different, whereas liver abscess scores linearly (P < 0.01) increased as more barley silage was replaced by wheat DDGS. Eating time (min/d) and duration of each meal linearly (P < 0.02) decreased, whereas eating rate (min/g of DM) linearly (P < 0.01) increased with increasing replacement of barley silage. Blood urea N was doubled (P < 0.01) compared with CON by inclusion of wheat DDGS. Results indicate that wheat DDGS can be used effectively in feedlot diets, decreasing the need for barley grain or silage without negatively affecting growth performance and carcass characteristics. A reduction in the amount of roughage required to maintain growth performance is a potential advantage in feedlot operations because forage is costly and often of limited availability. Thus, DDGS can be a possible alternative as long as they are available and cost effective; however, increased incidence of liver abscess and increased N content of manure need to be considered when greater amounts of wheat DDGS are included in finishing diets.

Effect of Triticale Dried Distillers Grains with Solubles on Ruminal Bacterial Populations as Revealed by Real Time Polymerase Chain Reaction

Real time PCR was used in this study to determine the effect of triticale dried distillers grains with solubles (TDDGS) as a replacement for grain or barley silage in finishing diets on the presence of six classical ruminal bacterial species (Succinivibrio dextrinosolvens, Selenomonas ruminantium, Streptococcus bovis, Megasphaera elsdenii, Prevotella ruminicola and Fibrobacter succinogenes) within the rumen contents of feedlot cattle. This study was divided into a step-wise adaptation experiment (112 days) that examined the effects of adaptation to diets containing increasing levels of TDDGS up to 30% (n = 4), a short-term experiment comparing animals (n = 16) fed control, 20%, 25% or 30% TDDGS diets over 28 days, and a rapid transition experiment (56 days) where animals (n = 4) were rapidly switched from a diet containing 30% TDDGS to a barley-based diet with no TDDGS. It was found that feeding TDDGS as replacement for barley grain (control vs. 20% TDDGS) decreased 16S rRNA copy numbers of starch-fermenting S. ruminantium and S. bovis (p<0.001 and p = 0.04, respectively), but did not alter 16S rRNA copy numbers of the other rumen bacteria. Furthermore, feeding TDDGS as a replacement barley silage (20% vs. 25% and 30% TDDGS) increased 16S rRNA copy numbers of S. ruminantium, M. elsdenii and F. succinogenes (p<0.001; p = 0.03 and p<0.001, respectively), but decreased (p<0.001) the 16S rRNA copy number of P. ruminicola . Upon removal of 30% TDDGS and return to the control diet, 16S rRNA copy numbers of S. ruminantium, M. elsdenii and F. succinogenes decreased (p = 0.01; p = 0.03 and p = 0.01, respectively), but S. dextrinosolvens and S. bovis increased (p = 0.04 and p = 0.009, respectively). The results suggest that replacement of TDDGS for grain reduces 16S rRNA copy numbers of starch-fermenting bacteria, whereas substitution for barley silage increases 16S rRNA copy numbers of bacteria involved in fibre digestion and the metabolism of lactic acid. This outcome supports the contention that the fibre in TDDGS is highly

Comparison of wheat or corn dried distillers grains with solubles on rumen fermentation and nutrient digestibility by feedlot heifers1

A 5 × 5 Latin square design trial was conducted to evaluate rumen fermentation and apparent nutrient digestibility in 5 rumen-cannulated heifers (420 ± 6 kg) fed a barley-based finishing diet supplemented with 20 or 40% wheat or corn dried distillers grains with solubles (DDGS). The composition of the control diet was 88.7% rolled barley grain, 5.5% supplement, and 5.8% barley silage (DM basis). Increasing the quantity of corn DDGS in the ration resulted in a quadratic decrease in DMI (P = 0.04) and OM intake (P = 0.05). Rumen pH, pH duration, and area under rumen pH thresholds of 5.8 or 5.5 were not affected (P > 0.05) by treatment. Inclusion of wheat DDGS resulted in a quadratic increase (P = 0.05) in pH area below the cutoff value of 5.2, with the most pronounced effect at 20% inclusion. Wheat DDGS linearly increased (P = 0.01) rumen NH(3)-N concentrations. Increasing the inclusion rate of wheat and corn DDGS resulted in quadratic (P = 0.05) and linear (P = 0.04) decreases in rumen propionate, whereas butyrate increased quadratically (P < 0.01) and linearly (P < 0.01), respectively. Feeding wheat DDGS linearly decreased (P < 0.01) DM and OM digestibility values. Inclusion of corn DDGS increased the digestibility values of ether extract (P = 0.05; quadratic response) and CP (P < 0.01; linear response). Neutral detergent fiber digestibility increased in a linear fashion (P = 0.01) as both wheat and corn DDGS inclusion increased, whereas ADF digestibility increased linearly (P = 0.03) for wheat and quadratically (P = 0.02) for corn DDGS. Increased inclusion of wheat DDGS resulted in a linear decrease in GE digestibility (P = 0.01), whereas increasing corn DDGS inclusion linearly increased (P < 0.01) the DE content of the diet. Feeding both wheat and corn DDGS linearly increased (P = 0.01) the excretion of N and P. In summary, replacement of barley grain with up to 40% wheat or corn DDGS did not mitigate rumen pH conditions associated with mild to moderate acidosis in heifers fed a barley-based finishing diet. Supplementing corn DDGS increased nutrient digestibility of all nutrients and, as a result, led to greater DE content. Supplementation of wheat DDGS reduced DM and OM digestibility values, with no effect on DE content. Increased N and P excretion by heifers fed DDGS at 20 or 40% of dietary DM presents a challenge for cattle feeders with respect to nutrient management.

Evidence of residual feed intake reranking in crossbred replacement heifers

The objective of the study was to examine whether residual feed intake (RFI) reranking exists between 2 consecutive periods in replacement heifers fed the same diet. The study collected feed intake and BW data from 190 crossbred heifers over a 3-yr period (61 in 2007, 68 in 2008, and 61 in 2009) during the winter-spring season. The heifers were fed a roughage-based diet (90% barley silage and 10% rolled barley grain) throughout the feeding trial, which was broken down into 2 feeding periods with ADG of 0.94 and 0.90 kg•d(-1) in the first and second periods, respectively. The RFI was calculated for the entire period using different models, which included ADG, mid-metabolic BW, body composition, and feeding activity. Gain:feed ratio and Kleiber ratio were also calculated. Rank correlations among the RFI calculated from different models were obtained, as well as rank correlations between the 2 feeding periods for the feed efficiency measures. Including body composition and feeding activity only improved the R(2) by 1 to 5%. The rank correlations among the different models were high (90 to 95%) for RFI calculated for the entire feeding period. However, the RFI calculated within the second feeding period had greater rank correlation than the RFI calculated from the entire feeding period. Compared with G:F and Kleiber ratio, RFI gave lesser reranking between periods 1 and 2. About 49% of the heifers maintained their RFI class, whereas 51% of the heifers had a different RFI class in period 2. Furthermore, 41% of the heifers changed their RFI in period 2 by <0.5 SD, whereas the rest of the heifers changed by ≥0.5 SD. These results indicate that reranking exists in heifers despite receiving the same diet in the 2 feeding periods and that the reranking may be more serious in heifers (28%) with extreme RFI performances in each period.

Effects of cinnamon leaf, oregano and sweet orange essential oils on fermentation and aerobic stability of barley silage

Silage additives are marketed with the primary aim of improving the fermentation and/or aerobic stability of silage. The objective of this study was to evaluate the impact of three different essential oils (EOs; cinnamon leaf (CIN), oregano (ORE) and sweet orange (SO)) on the fermentation characteristics and stability of barley silage. Chopped whole-plant barley (Hordem vulgare L.) forage was ensiled either untreated (0 mg kg⁻¹ dry matter (DM)) or treated with CIN, ORE or SO (37.5, 75 and 120 mg kg⁻¹ DM). Moulds were not detected in any treatments, including the control, after 7 days of air exposure. All EOs at a concentration of 120 mg kg⁻¹ silage DM decreased (P = 0.001) yeast populations in comparison with the control during air exposure. Net gas, methane and ammonia concentrations in vitro did not differ among treatments. Changes in volatile fatty acid concentrations were small, and in situ data showed no changes in DM and neutral detergent fibre digestion rates for CIN, ORE or SO at concentrations up to 120 mg kg⁻¹ DM. The findings from this study show that a concentration of 120 mg EO kg⁻¹ DM decreased yeast counts during aerobic stability tests. However, all EO treatments had minimal effects on data from in vitro and in situ incubations.

Optimum extent of barley grain processing and barley silage proportion in feedlot cattle diets: Growth, feed efficiency, and fecal characteristics

Koenig, K. M. and Beauchemin, K. A. 2011. Optimum extent of barley grain processing and barley silage proportion in feedlot cattle diets: Growth, feed efficiency and fecal characteristics. Can. J. Anim. Sci. 91: 411–422. A study was conducted to evaluate the effects of forage proportion and extent of processing of barley grain on growth, intake, feed conversion efficiency, and fecal characteristics of feedlot cattle. Crossbred steers (120; 407±31 kg) were housed individually and assigned to 10 diets (n=12): two degrees of temper rolling of barley grain [processing index (PI) of 82% (standard) or 87% (coarse)] were combined with five levels of barley silage [3, 6, 9, 12, and 15% of dietary dry matter (DM)]. The PI was determined as the weight of grain after processing expressed as a percentage of the weight before processing. Cattle were slaughtered after 104–109 d on feed, at a final weight of 576 kg, SEM = 5.1. There were very few interactions between grain processing and silage proportion for the variables measured. Grain processing had no effect (P&gt;0.05) on average daily gain (1.59 kg d−1, SEM = 0.057) or final weight. Feeding PI-87% barley tended to increase dry matter intake (DMI) over the experiment (7.63 vs. 7.34 kg d−1, SEM = 0.123, P=0.10) compared with feeding PI-82% barley. Higher DMI of cattle fed PI-87% barley corresponded to lower estimated starch digestibility, as a result of increased appearance of whole kernels and grain fragments in feces. Consequently, gain:feed ratio tended (0.210 vs. 0.219, SEM = 0.0035, P=0.06) to decrease by 4% with PI-87% versus PI-82% barley. Similarly, silage proportion had no effect on gain but DMI increased (P=0.05) linearly from 7.19 to 7.75 kg d−1 (SEM = 0.194) with increasing proportion of silage. Consequently, gain:feed ratio decreased linearly from 0.225 to 0.202 (SEM = 0.0056) with increasing silage proportion. Optimum proportion of barley silage to maximize feed conversion efficiency was 3 to 6% of DM. Decreasing the extent of barley processing or increasing the silage proportion may reduce the risk of acidosis, but feed conversion efficiency is lowered. Formulating diets to reduce the incidence of digestive disorders may decrease the cost of mortalities and treatment of sick animals, thereby improving animal health and welfare, but these costs are unlikely to offset the increased cost of gain in commercial feedlots.

조사료원에 따른 한국 재래산양의 채식습성에 관한 연구

The object of this experiment was to investigate the food habits of Korean native goats fed with various roughage sources. The experimental trials were conducted at Unbong Animal Genetic Resources Station in 2008. The experimental roughages include five sources and 25 species in all; grasses and legumes: 5 species (mixed grasses, orchardgrass, tall fescue, alfalfa, white clover), native grasses and weeds: 5 species (mixed native grasses, Miscanthus sinensis Anderss, Arundinella hirta (Thunb.) Tanaka, Barnyard grass, short awn, forage crops and straw: 5 species (barley + hairy vetch wheat + hairy vetch, rye silage, barley silage, baled rice straw), browse and fallen leaves: 5 species (Mixed browse, Oriental white oak, Quercus serrta Thunb., Oriental cherry fallen leaves, Japanese chestnut fallen leaves), and imported hay and straw: 5 species(timothy hay, tall fescue straw, annual ryegrass straw, klinegrass hay, alfalfa hay). Ten Korean native goats were selected which had nearly the same body weight (average 24±2.8 kg). The chemical composition and dry matter digestibility of each roughage source and species were significantly different at the sampling area, plant species, growth stages and cutting period (p<0.05). Among all the 25 species of roughages, the favorite intake species order by Korean native goat was observed like this: Quercus aliena, Querancas serrta Thunb and Mixed browse, which was a lower intake compared to other domestic herbivores. The Korean native goats ate more roughages which had low fibrous contents, but high dry matter digestibility. The Korean native goats ate more roughages which had low fibrous contents, but high dry matter digestibility. On the other hand, compared to each roughage source, total intake amount by Korean native goats was showed as browse and fallen leaves (33.1%) among trials roughage sources. Based on these results, the food habit of Korean native goats seems to be closer to the browser.

Starch source and content in postpartum dairy cow diets: Effects on plasma metabolites and reproductive processes

The objective of this study was to examine the effects of dietary starch source and content in the immediate postpartum period on plasma metabolites and hormones and ovarian follicular development. One of 3 diets was fed in a randomized block design to 40 cows from calving until 70 d in milk. The diets contained 45% alfalfa silage (AS), 45% barley silage (BS), or 41% barley silage and 4% supplemental starch (SS) on a dry matter basis. All diets contained 45% barley-based concentrate and 10% alfalfa hay. Resulting starch levels were 25.2, 23.3, and 26.7% for AS, BS, and SS, respectively. Body condition was scored every other week and dry matter intake and milk yield were recorded daily. Milk samples were obtained weekly and blood samples were taken at calving and then every other week to determine concentrations of glucose, insulin, insulin-like growth factor-1, β-hydroxybutyrate, and nonesterified fatty acids. Transrectal ultrasonography was performed twice per week from 7 d after calving until first ovulation or 62 d in milk in all cows. For a subset of 7 AS-, 8 BS-, and 9 SS-fed cows, a complete estrous cycle was monitored for ovarian dynamics, and blood samples were collected every second day for progesterone and estradiol. Luteinizing hormone pulsatility was also determined (5 cows/treatment) approximately 15 d postcalving. Treatment had no effect on body condition score, dry matter intake, blood metabolites, milk yield, or milk fat and protein contents, but BS-fed cows had significantly higher levels of milk urea nitrogen compared with SS cows. Cows fed SS (31 d) tended to have a shorter interval from calving to first ovulation than cows fed AS (43 d) or BS (38 d). The incidence of double first ovulations was higher in cows fed SS (46%) compared with those fed BS (0%). Treatment had no effect on LH pulse frequency or amplitude, ovarian dynamics, or progesterone and estradiol concentrations during the observed estrous cycle. Energy balance did not differ among cows fed the 3 diets. Overall, dietary starch source and concentration had little effect on productivity or metabolic status of postpartum cows.

Barley and triticale underseeded with a kura clover living mulch: Effects on weed pressure, disease incidence, silage yield, and forage quality

Kosinski, S. M., King, J. R., Harker, K. N., Turkington, T. K. and Spaner, D. 2011. Barley and triticale underseeded with a kura clover living mulch: Effects on weed pressure, disease incidence, silage yield, and forage quality. Can. J. Plant Sci. 91: 677–687. Our objective was to evaluate the effects of seeding barley (Hordeum vulgare L.) and triticale (×Triticosecale wittmack) into a living mulch of kura clover (Trifolium ambiguum M. Bieb.) on weed pressure, barley leaf disease levels, silage yield, and forage quality. Field studies were conducted at two locations in the Parkland region of Alberta, Canada, in 2006 and 2007. Barley and triticale were seeded, at three different soil nitrogen levels, into an established living mulch of kura clover that was either unsuppressed or chemically suppressed with glyphosate at 0.41 kg a.i. ha−1prior to cereal seeding. Barley and triticale sole crops were also included for comparison. The presence of the suppressed and unsuppressed kura clover living mulches significantly decreased weed pressure in 2007 and barley leaf disease incidence in 2006 and 2007. Silage DM yield of the cereal sole crops ranged from 5.18 to 7.02 Mg ha−1, compared with yields of 4.57 to 5.21 Mg ha−1from the unsuppressed living mulch treatments and from 3.95 to 6.00 Mg ha−1from the suppressed living mulch treatments. The kura clover increased the relative feed value of the silage. Based on these results, there is the potential for a suppressed kura clover living mulch to be utilized for cereal silage production in Alberta.

Chopping of whole-crop barley silage improves intake and live-weight gain of young dairy steers

This experiment evaluated the effect of chopping whole-crop barley silage on intake, diet selection and live-weight gain in young dairy steers. Whole-crop barley harvested at the dough stage of maturity and preserved as round bale silage was fed ad libitum in its long form or precision-chopped to 63 pen-housed dairy steers (average weight 173, s.d. 39kg). In addition, each animal received 0.6kg of soybean meal, 0.4kg of barley grain and 0.08kg of mineral feed daily. Chopping increased dry matter intake of whole-crop barley silage by 23% and live-weight gain by 22%. Higher concentrations of starch in the orts from steers when fed unchopped silage reflected sorting against grain, probably caused by long awns in the unchopped silage, which were not present in the chopped silage. No sorting against grain occurred in the chopped silage. Chopping increased intake of whole-crop barley silage and live-weight gain of young dairy steers, probably due to negative effects of long awns in the unchopped whole-crop barley silage on intake.

Effects of grain-pellet and alfalfa-pellet subacute ruminal acidosis (SARA) challenges on feeding behaviour of lactating dairy cows

Li, S., Khafipour, E., Krause, D. O., González, L. A. and Plaizier, J. C. 2011. Effects of grain-pellet and alfalfa-pellet subacute ruminal acidosis (SARA) challenges on feeding behaviour of lactating dairy cows. Can. J. Anim. Sci. 91: 323–330. The effects of two nutritional challenges aimed at inducing subacute ruminal acidosis (SARA) on the feeding behaviour of lactating dairy cows were investigated in two separate experiments. Both experiments included eight tie-stall-housed cows that were fed once daily. Feeding behaviour of individual cows was monitored by continuously weighing the feed in the mangers. In each experiment, ruminal pH was monitored in four rumen cannulated cows. In the first experiment, cows received a control diet containing 50% mixed concentrate and 50% alfalfa and barley silage (DM basis) during weeks 1 to 5 of two subsequent 6-wk periods. During week 6 of both periods, a grain-pellet SARA challenge (GPSC) was conducted by replacing 21% of DM of the basal diet with wheat-barley pellets. Data obtained in week 4 were taken as a control. In the second experiment, cows received a control diet containing 50% of DM as mixed concentrate and 50% of DM as chopped alfalfa hay during the first week of a 5-wk period. Between week 2 and week 5, an alfalfa-pellet SARA challenge (APSC) was conducted by replacing alfalfa hay in the control diet with alfalfa pellets at a rate of 8% per week. Week 1 and week 5 were considered as the control and SARA challenge, respectively. In the first experiment, the GPSC reduced the meal duration from 48.9 to 38.6 min meal−1 and the eating time from 6.7 to 5.5 h d−1. Meal criteria, meal frequency, meal size, and eating rate were not affected. In the second experiment, the APSC did not affect the meal criterion, meal duration, and eating time per day, but increased dry matter intake from 18.7 to 24.3 kg d−1, meal frequency from 8.2 to 9.4 meals d−1, meals size from 2.4 to 2.7 kg DM, and eating rate from 54.8 to 67.6 g DM min−1. The duration of the first meal after feed delivery was reduced from 154.5 to 103.6 min by the GPSC and from 146.7 to 112.2 min by the APSC. This reduction in the duration of the first meal was accompanied by a reduction in the drop of the ruminal pH during the GPSC, but not during the APSC. Only the APSC increased eating rate of the first meal. Other parameters of this first meal were not affected by both challenges.

The effects of feeding flaxseed to beef cows given forage based diets on fatty acids of longissimus thoracis muscle and backfat

This study was conducted to investigate changes in fatty acid profiles of beef cows fed grass hay or barley silage based diets, with or without flaxseed supplementation. Both flaxseed and hay feeding increased levels of α-linolenic acid (LNA; 18:3n-3) in longissimus thoracis and backfat (P<0.001). A forage type by flaxseed level interaction was observed for most LNA biohydrogenation intermediates (P<0.05) that indicated feeding hay combined with flaxseed led to the greatest levels of total conjugated linolenic acid, total conjugated linoleic acid, total non-conjugated dienes and total trans-18:1. Predominant biohydrogenation intermediates included t11,c15-18:2, rumenic acid (c9,t11-18:2) and vaccenic acid (t11-18:1).