Glycaemic responses and hypocholesterolaemic effects of high-amylose barley diets on broiler chicks

The glucose and lipid responses of barley diets were investigated with chicks based on either flour or red dog (RD) from each of three barley cultivars, Glacier, covered high-amylose Glacier (HAG) and hull-less high-amylose Glacier (HHAG), with two maize control diets. Mean time interval blood glucose levels were higher (P<0·05) for chicks fed uncooked barley flour or RD, compared with controls. Total and LDL plasma cholesterol were lower (P<0·05) for chicks fed the HAG and HHAG flour and all barley RD diets. HDL cholesterol values for chicks fed Glacier and HHAG flour and HHAG RD diets were higher than controls. The LDL/HDL cholesterol ratios for chicks fed HAG and HHAG flour and all barley RD diets were lower (P<0·05) than controls. Lower body weights were observed in all chickens fed barley diets. The results suggest that the soluble fibre, mainly β-glucan and starch structures, in barley may be responsible for the hypocholesterolaemic effect. © 1998 SCI.     

Phosphorus characterization in feces from broiler chicks fed low‐phytate barley diets

The inclusion of low phytate grains in poultry diets can reduce the phosphorus (P) content of poultry feces, but their influence on fecal P composition is not well established. To assess this, 100 male broiler chicks (21 days old) were fed dietary treatments based on either a wild‐type barley or one of three low phytate mutant barleys with 59, 62 and 99% reductions in phytate P, compared with the normal barley diet. The birds were housed in raised‐floor battery cages with mesh grate floors above fecal collection trays with five birds per pen and five pens per treatment. The birds were fed for 9 days and feces were collected twice a day during the last 2 days of the experiment. Total P concentrations were 14–24% lower in feces from birds fed low phytate barley diets compared with those fed the normal barley diet. Phosphorus digestibility increased (P < 0.05) as phytate in the barley diet decreased. Phosphate was the major P fraction in the feces (69–75% extracted P) regardless of the type of barley fed. Phytate constituted only 3–12% of the P in the feces, indicating its hydrolysis in the bird. Overall, these results suggest that feeding low‐phytate barley diets can reduce P concentrations in poultry feces without causing significant changes in P composition. Copyright © 2007 Society of Chemical Industry     

Estimation of metabolisable energy content of date pit and its effect on lipid and protein oxidation in broiler chicks

BACKGROUND: Two experiments were conducted to evaluate date pit as a feed ingredient in broiler chick diets. In the first experiment, apparent metabolisable energy (AME) of date pit was determined using 72 Ross (308) broiler chicks. Broiler chicks received experimental diets from 25 to 30 days of age. Two diets were fed: diet 1, basal diet and diet 2, 60% basal diet + 40% date pit. Date pit ileal AME_n was estimated to be 704 kcal kg^?1. The second study was conducted to evaluate the AME_n value obtained and also the effectiveness of using a commercial multi‐enzyme in diets containing date pit. Diets with three levels of date pit (10, 20 and 30% date pit) with or without enzyme supplementation were fed to broiler chicks from day old to 42 days of age. RESULTS: Chicks receiving different levels of dietary date pit had comparable body weight to those fed on corn–soybean meal diet. Both date pit levels and enzyme supplementation had a significant effect on feed conversion ratio. Plasma total antioxidant levels of positive control were significantly lower than the experimental diets. CONCLUSION: Results obtained in our study suggested that date pit could be used as a feed ingredient in the diet of broiler chicks without any negative effect on performance. Furthermore, date pit may have beneficial effects on plasma antioxidant status in broiler chicks. Copyright © 2009 Society of Chemical Industry     

Effect of ammoniated barley silage on ruminal fermentation, nitrogen supply to the small intestine, ruminal and whole tract digestion, and milk production of Holstein cows

The effect of ammonia on barley silage fermentation characteristics, and the digestion and utilization of ammoniated barley silage by lactating Holstein cows fed three isonitrogenous diets (14.5% CP, DM basis) were examined. Whole plant barley was chopped and treated with anhydrous ammonia (1%, DM basis) at ensiling. Untreated barley silage was supplemented with either canola meal or urea. Cows were fed complete mixed diets (50% silage and 50% concentrate mixture, DM basis). Addition of ammonia increased total N, water-insoluble N, lactic acid, and pH in silage. Based on the application rate, 77.7% of the added ammonia N was recovered, and increased water-insoluble N was equal to 49.8% of added ammonia N. Addition of ammonia to barley silage increased ruminal concentrations of ammonia and propionate, and supplies of nonammonia N, microbial N, and total N to the small intestine. Ruminal effective degradabilities of DM and CP of barley silage and complete mixed diets, and whole tract digestibility of DM and CP of complete mixed diets were not affected by supplemental N source. Milk yield and milk composition of cows fed the ammoniated barley silage were similar to those of cows fed the diets supplemented with canola meal or urea.     

DISTRIBUTION OF OCHRATOXIN A IN CHICKEN TISSUES AND EGGS

The kinetics of distribution of ochratoxin A (OA) in chicken tissues was studied. Day-old chicks were fed a starter diet alone or containing 1 ppm OA. After 5 weeks, all chicks were intubated with 50 μg ³H-OA per chick. The highest level of radioactivity was found in kidney and liver 8 hr after intubation. Peak levels of OA in kidney, liver and breast were found to be 12, 4, and 0.2 ppb, respectively. Over 90% of the radioactivity was eliminated 48 hr after intubation. Moreover, when laying hens were fed a diet containing 0.5 or 5.0 ppm of OA for 2 weeks, the highest levels of OA were found in the kidney (124 ppb) and liver (80 ppb) also. Levels of OA in breast, leg and eggs of laying hens were found to be 8, 7, and 2.8 ppb, respectively.     

Digestion and utilization of high moisture barley by lactating dairy cows

Two experiments were conducted to study digestion and utilization of dry and high moisture barley. Dry matter yield of dry barley was 2.99 tonnes/ha in contrast to 3.58 tonnes/ha for high moisture barley. In Experiment 1, 38 cows in early to midlactation were assigned to two diets (40% alfalfa hay; 9.4% supplement and 50.6% barley, DM basis) that differed only in the type of barley fed: diet 1, rolled dry barley, and diet 2, rolled high moisture barley. Although DM intake, milk yield, and 4% FCM were not significantly influenced by diet, cows fed diet 2 had higher milk persistency than those fed diet 1. In Experiment 2, three lactating cows fitted with ruminal and duodenal cannulae were assigned to three dietary treatments in a Latin square design. Diets 1 and 2 were as in Experiment 1, whereas diet 3 contained ground high moisture barley. Digestibility coefficients tended to be lower and duodenal starch percent higher for cows fed diet 3 than those fed diets 1 or 2. No significant dietary differences were observed in ruminal pH, VFA, or ammonia concentrations. Although ensiling and processing influenced the rate and extent of DM and CP degradation in situ, treatment did not influence effective degradability. Results suggest that the feeding value of high moisture barley for lactating cows is equivalent to dry barley on a DM basis.     

Long term administration of low doses of mycotoxins in poultry. 2. Residues of ochratoxin A and aflatoxins in broilers and laying hens after combined administration of ochratoxin A and aflatoxin B1

The effects of combined administration of ochratoxin A (OA) and aflatoxin B1 (AFB1) on the occurrence and the levels of residues of mycotoxins in poultry have been investigated. Male broilers and laying hens were fed from 14 days old with standard diets contaminated with 50 micrograms/kg OA and 50 micrograms/kg AFB1. Two groups of broilers and hens were withdrawn from contaminated feed at 37 and 88 days, respectively. At the time of sacrifice no significant lesions were found. Residues were compared with those found after administration of either toxin alone in former trials. Combined treatment resulted in higher content of OA in broiler livers (40 versus 5.0 micrograms/kg) and, to a lesser extent, in kidneys and skin, and of AFB1 in broiler liver and kidney (0.15 versus 0.02 microgram/kg and 0.40 versus 0.05 microgram/kg respectively). Laying hens showed smaller differences (0.20 versus 0.10 microgram/kg in liver and 0.32 versus 0.08 in kidneys). Withdrawal from treatment led to the almost complete disappearance of OA residues in broilers and in hens. These results show a synergistic effect of OA and AFB1, particularly in broilers.     

The effect of delayed ensiling and application of a propionic acid-based additive on the fermentation of barley silage

Prolonged exposure to air can adversely affect the silage fermentation process. To investigate a possible method to overcome this problem, we determined if a buffered propionic acid-based additive, applied to chopped, whole-plant barley exposed to air before ensiling, would affect the subsequent fermentation. Wilted forage was chopped and treated with nothing, or with 0.1% (wt/wt wet forage) of a buffered propionic acid-based additive and ensiled immediately in quadruplicate 20-L laboratory silos. Portions of the chopped forage, untreated and treated, were left in loose piles in a barn for 24 h before ensiling. Another portion of the untreated silage exposed to air for 24 h was also treated with 0.1% of the additive just before ensiling. Prolonged exposure to air before ensiling increased the numbers of yeasts on forages by more than 1,000-fold. The concentrations of water-soluble carbohydrates decreased by more than 50%; the ammonia-N concentrations increased 40%, and pH increased by more than 1 unit as a result of exposure to air. These changes were less in forage that was treated with the additive at chopping. After 60 d, silages of forages that were exposed to air before ensiling had a higher pH, higher concentrations of ammonia-N and butyric acid, and lower concentrations of lactic and acetic acids than silages of forage that had been ensiled immediately after harvest. In situ DM digestibility was lowest in untreated silages that had been exposed to air before ensiling. In contrast, treatment with the additive, applied before or after exposure to air, prevented the reduction in in vitro digestion.     

Utilization of ensiled corn crop residues by Holstein heifers.

Corn crop residues were harvested 1 to 2 d after harvest of high moisture corn. Half the harvested residues were treated with an aqueous solution of ammonia before ensiling to give 34 g of ammonia/kg of residue DM. The untreated half was the control silage. Both silages were ensiled in bunker silos. More residues were harvested 2.5 wk later from the same field and combined with Brassica napus L. before ensiling in a bag, and this constituted the third forage treatment. Three diets containing 48.8, 46.5, and 63.8% residue silage (DM basis), with the latter containing corn crop residue and brassica in a 3:1 ratio, were designated as control, ammoniated, and brassica, respectively. The other ingredients of the diet were alfalfa silage, cracked corn, and urea. The diets were fed to Holstein heifers averaging 186 kg (light BW) and 372 kg (heavy BW). Weight gains were similar at 84 d for heifers fed the control and the ammoniated residue diets. Light and heavy heifers gained 619 and 631 g/d with the control diet and 678 and 631 g/d with the ammoniated residue diets. At 70 d, the heavy heifers fed control, ammoniated, and brassica diets had weight gains of 629, 671, and 786 g/d, respectively. Digestion coefficients were similar between the control and ammoniated residue diets: DM (62.6 and 58.7%), NDF (56.7 and 56.2%), and ADF (56.3 and 55.8%). Ammonia treatment of corn crop residue silage had no effect on animal performance or digestibility. Brassica appeared to improve animal performance when it was mixed with corn crop residue silage.     

Effects of moisture content of complete diets on feed intake and milk production by cows

In two trials, 47 and 54 Holstein cows were fed diets containing ensiled forages, ensiled and dry forages, or diets of different moisture contents. In trial 1, diets were fed during a preliminary dry period, early lactation, late lactation, a second dry period, and a second early lactation. In trial 2, four diets identical except for moisture content (78, 64, 52, and 40% dry matter) were fed for the first 200 days of lactation. Substitution of dry hay for alfalfa silage increased dry matter intake during the first early lactation, whereas partial substitution of corn silage with straw did not affect intake during dry periods. Dry matter intake increased linearly as dry matter content of diet increased in trial 2. Neither milk production nor body weight were affected by treatment in either trial. Percentage total solids increased linearly as dry matter content of diet decreased in trial 2. Volatile fatty acids differed slightly, but no trends were consistent. No differences of daily chewing time were observed. From these trials, diets of less than 60 to 65% dry matter may reduce intake by lactating dairy cows.     

The influence of dietary copper concentration on hepatic copper in the duckling and the chick

Following a field outbreak, in which many ducklings were lost after being fed an otherwise conventional diet containing over 200 parts/million copper, a series of small trials were conducted in which diets high in copper were fed to Khaki Campbell ducklings and to Light Sussex × Rhode Island Red chicks. The only losses that occurred were on days following weighing days, but the domestic duckling was found to accumulate copper in its liver to a much greater degree than the domestic chick, the results in this respect resembling those of Beck on the young muscovy. Species variation in dietary copper uptake, distribution and toxicity are discussed.     

Effects of planting date on fiber digestibility of whole-crop barley and productivity of lactating dairy cows

Objectives of the study were to evaluate the effect of planting date on in vitro neutral detergent fiber digestibility (IVFD) of whole-crop barley (Hordeum vulgare) and its effects on productivity of lactating dairy cows. Two cultivars of barley were planted on May 5 (BM) and June 7 (BJ), 2005 at the Edmonton Research Station, University of Alberta. They were harvested at late-dough stage on July 26 and August 25, respectively, for BM and BJ and ensiled. The BJ had greater 30-h IVFD (61.2 vs. 51.9%) and crude protein concentration (12.4 vs. 8.7%) at harvest compared with BM. Thirty lactating cows, including 6 ruminally cannulated cows, in mid to late lactation (183 ± 71.7 d in milk; mean ± standard deviation) were fed diets containing BM or BJ at 58.5% of dietary DM in a crossover design with 19-d periods. The dietary neutral detergent fiber concentration was 30.6 and 28.8% for BM and BJ diets, respectively. Dry matter intake and milk yield were not affected by treatment and averaged 20.2 and 27.2 kg/ d, respectively. The lack of responses could have been attributed to the low-energy demands for cows used in this experiment; ruminal physical fill might not have limited dry matter intake. However, cows fed BJ had greater total tract dry matter digestibility (68.9 vs. 66.1%) and tended to increase body weight gain (864 vs. 504 g/d) compared with those fed BM. Delaying the planting date of barley altered its growing environment and affected nutrient composition and IVFD of whole-crop barley and energy availability to animals. Further research is needed to confirm if the planting date consistently affects nutrient composition and IVFD of barley at harvest.     

The effect of different grain diets on fecal shedding of Escherichia coli O157:H7 by steers

Three groups of six yearling steers (three rumen fistulated plus three nonfistulated) fed one of three different grain diets (85% cracked corn, 15% whole cottonseed and 70% barley, or 85% barley) were inoculated with 10(10) CFU of Escherichia coli O157:H7 strain 3081, and the presence of the inoculated strain was followed in the rumen fluid and feces for a 10-week period. E. coli O157:H7 was rapidly eliminated from the rumen of the animals on all three diets but persisted in the feces of some animals up to 67 days after inoculation, suggesting that the bovine hindgut is the site of E. coli O157:H7 persistence. A significant difference existed in the levels of E. coli O157:H7 shed by the animals among diets on days 5, 7, 49, and 63 after inoculation (P < 0.05). No significant difference was found between the levels shed among diets on days 9 through 42 and on day 67 (P > 0.05). The number of animals that were culture positive for E. coli O157:H7 strain 3081 during the 10-week period was significantly higher for the barley fed group (72 of 114 samplings) as opposed to the corn fed group (44 of 114 samplings) (P < 0.005) and the cottonseed and barley fed group (57 of 114 samplings) (P < 0.05). The fecal pH of the animals fed the corn diet was significantly lower (P < 0.05) than the fecal pH of the animals fed the cottonseed and barley and barley diets, likely resulting in a less suitable environment for E. coli O157:H7 in the hindgut of the corn fed animals. E. coli O157:H7 strain 3081 was present in 3 of 30 (corn, 1 of 10; cottonseed, 1 of 10; barley, 1 of 10) animal drinking water samples, 3 of 30 (corn, 1 of 10; cottonseed, 0 of 10; barley, 2 of 10) water trough biofilm swabs, 5 of 30 (corn, 0 of 10; cottonseed, 2 of 10; barley, 3 of 10) feed samples, and 30 of 30 manure samples taken from the pens during the entire experimental period. Mouth swabs of the steers were also culture positive for E. coli O157:H7 strain 3081 in 30 of 180 samples (corn, 7 of 60; cottonseed, 4 of 60; barley, 19 of 60) taken during the 10-week period. Minimizing environmental dissemination of E. coli O157:H7 in conjunction with diet modification may reduce numbers of E. coli O157:H7-positive cattle.     

Performance and carcass characteristics of growing pigs and broilers fed diets containing micronised barley,ground barley,wheat and maize

Two swine starter/grower/finisher trials utilising 216 24‐day‐old pigs and one 40‐day broiler growth trial utilising 1920 1‐day‐old chicks were conducted to determine the influence of dietary micronised dehulled barley (MDB) as a replacement for hulled barley (HB), wheat (W) and maize (M) on live performance, carcass and meat measurements, organ weights (swine), plasma urea nitrogen (PUN) level (swine) and intestinal digesta viscosity (broilers). Dehulling and micronising the barley reduced crude protein by 20%, neutral detergent fibre by 17% and amino acids by varying amounts. Replacing M or W with MDB in swine diets had no effect (P > 0.05) on any measured parameter, with the exception of decreased PUN (P = 0.03) when MDB replaced 100% of W. Broilers fed W, M or HB generally had similar live performance, carcass traits and digesta viscosity, with the exception of reduced (P < 0.05) average daily gain and average daily feed intake for HB during the first 20 days of the trial. However, broilers fed MDB had slightly reduced (P = 0.05) live performance during each phase of the trial and greatly increased (P = 0.01) digesta viscosity. Addition of a commercial enzyme product to the diets reversed the reduced performance and increased the digesta viscosity of the MDB diet, but generally had no influence in the W, M and HB diets. These results suggest that MDB can be utilised in swine diets without affecting performance, but that reduced performance may result from its use in broiler diets. © 2001 Society of Chemical Industry     

Effects of inoculation of high dry matter alfalfa silage on ensiling characteristics,ruminal nutrient degradability and dairy cow performance

The objective of this study was to determine the effects of a homolactic acid inoculant on ensiling characteristics and nutritive value of high dry matter (DM) alfalfa. The ensiling characteristics were determined by ensiling inoculated and untreated alfalfa haylage in mini‐silos for 0, 2, 4, 8, 16 and 45 days. Two lactating cows fitted with ruminal fistulas were used to determine ruminal degradabilities of nutrient in inoculated and untreated alfalfa silage (45‐day silage). Effects of feeding inoculated and untreated alfalfa silage on animal performance were determined using 28 lactating dairy cows fed total mixed diets (40% forage and 60% concentrate) with the forage portion consisting of inoculated or untreated alfalfa silage. The pH of the inoculated silage declined from 5.9 to 4.5 within 2 days of ensiling while the pH of the untreated silage did not drop below 5 until day 16 post‐ensiling. At all ensiling times, inoculated alfalfa silage had lower pH than untreated alfalfa silage. The concentration of lactic acid was higher while that of water‐soluble carbohydrates was lower for inoculated than untreated alfalfa silage at all ensiling times. Inoculation increased proteolysis as indicated by a reduction in true protein and neutral detergent insoluble protein and an increase in non‐protein nitrogen. Ruminal degradability of DM, crude protein and neutral detergent fiber of alfalfa silage were not affected by inoculation. The average effective degradability of dry matter, crude protein and neutral detergent fiber was 66, 65 and 62%, respectively. Dairy cows fed inoculated alfalfa silage had DM intake (average 22 kg day^?1) and milk yield (average 42 kg day^?1) similar to cows fed untreated alfalfa silage. It was concluded that the inoculant used in this study improved the ensiling characteristics of alfalfa silage with no significant effects on dairy cow performance. Copyright © 2004 Society of Chemical Industry     

Prebiotic effects of fermentable carbohydrate polymers may be modulated by faecal bulking of non‐fermentable polysaccharides in the large bowel of rats

This study investigated the impact of supplementary fermentable polysaccharides inulin (a prebiotic) and barley β‐glucan on the large bowel, when consumed against a background high or low intake of mixed non‐starch polysaccharide. Rats were fed for 28 days with diets containing high (15%) and low (5%) background dietary fibre (BDF; cellulose plus sugar beet fibre), with or without 5% supplementary fermentable fibre (SFF; inulin or barley β‐glucan). High‐BDF diets unsupplemented with inulin or barley β‐glucan caused greater improvement than supplemented low‐BDF diets in several parameters linked to gut health: they increased colonic Bifidobacterium spp., butyric acid concentration in the caecum, and colonic crypt depth more than inulin and barley β‐glucan. For these parameters, inulin and barley β‐glucan added little to the effects of the high‐BDF diet alone. Furthermore, by allowing for dilution due to the greater faecal bulk induced by the mixed fibre compared with inulin or barley β‐glucan, the total quantity of butyric acid in the colon of BDF‐fed rats was greatly amplified. Interpretation of the effects of prebiotics in diets containing dietary fibre requires concurrent analysis of the multiple effects of non‐fermentable bulk.     

Starch source evaluation in calf starter: I. Feed consumption, body weight gain, structural growth, and blood metabolites in Holstein calves

Holstein calves were fed pelleted iso-starch (25% of starter dry matter) diets containing barley (n = 16), corn (n = 16), oat (n = 16), and wheat (n = 16) starch for 12 wk of age. Feed consumption, nutrient intake, body weight (BW) gain, skeletal growth, and selected blood metabolites in calves during preweaning (d 1 to 49) and postweaning (d 50 to 84) periods were measured. Average daily starter consumption during pre-weaning and postweaning periods was the greatest in calves fed corn died followed by those fed a wheat diet and then in those fed barley and oat diets. During the preweaning period, the calves provided corn and wheat diets consumed greater amount of mixed grass hay than those fed barley and oat diets. During the postweaning period, mixed grass hay intake was the greatest in calves provided corn diet followed by those fed a wheat diet and then in those fed barley and oat diets. Nutrients (dry matter, crude protein, starch, and neutral detergent fiber) intake followed the solid feed consumption pattern in calves. Body weight and body measurements (body length, body barrel, heart girth, wither height, and hip height) at birth and at weaning (d 49) in calves fed different starch sources were similar. Body weight and body measurements at postweaning (d 84) were the greatest in calves fed a corn diet followed by those fed a wheat diet and then in those fed barley and oat diets. Overall average BW gain and total dry matter intake were the greatest in calves fed a corn diet than in those fed wheat, barley, and oat diets. Feed efficiency was greater in calves fed corn and wheat diets than in those fed barley and oat diets. Blood glucose, blood urea N, triglycerides, cholesterol, and creatinine were reduced with the advancing age of calves. Lesser blood glucose and greater blood urea N concentrations at wk 8, 10, and 12 of age were noticed in calves fed corn diet than in those fed barley, oat, and wheat diets. Occurrence of diarrhea was more frequent in calves fed oat diet than in those provided barley, corn, and wheat diets. Starch sources did not influence respiratory score, rectal temperature, and general appearance score. In conclusion, the calves on corn diet consumed more solid feed and gained greater BW than those fed barley, oat, and wheat diets.     

Changes in ruminal bacterial community composition following feeding of alfalfa ensiled with a lactic acid bacterial inoculant

Some silage inoculants help to improve silage quality and promote an increase in milk production, possibly through altering the rumen microflora. We hypothesized that rumen bacterial community composition (BCC) would be different in cows fed alfalfa ensiled with the inoculant Lactobacillus plantarum MTD/1 (LP) compared with those fed alfalfa ensiled without the inoculant (Ctrl). Eight ruminally cannulated Holstein cows were allotted to 2 diets (Ctrl or LP) in a double crossover design with four 28-d periods. Diets were formulated to contain (% dry matter basis) 28.0% neutral detergent fiber and 16.2% crude protein, and contained alfalfa silage, 50.9; corn silage, 20.6; high-moisture shelled corn, 21.4; soy hulls, 4.7; plus minerals and vitamins, 2.4. Ruminal digesta were collected just before feeding on 3 consecutive days near the end of each period, and were separated into solid and liquid phases. Microbial DNA was extracted from each phase, amplified by PCR using domain-level bacterial primers, and subjected to automated ribosomal intergenic spacer analysis. The pH was 4.56 and 4.86 and the lactate-to-acetate ratio 9.8 and 4.4, respectively, for the treated and untreated alfalfa silages. Dry matter intakes and milk production data were not influenced by diets but showed a cow effect. Total volatile fatty acids (mM) tended to be greater for LP compared with Ctrl. Individual volatile fatty acids were not influenced by diets but showed a significant cow effect. Ruminal acetate (mol/100 mol) and acetate-to-propionate ratio were lower and propionate (mol/100 mol) greater for the 2 milk fat-depressed (MFD; <3.2% fat content) cows compared with the other 6 cows. Correspondence analysis of the 265 peaks in the automated ribosomal intergenic spacer analysis profile across the 188 samples revealed that the first 2 components contributed 7.1 and 3.8% to the total variation in the profile. The ordination points representing the liquid and solid phases clustered separately, indicating that these phases differed in BCC. The analysis of similarity data showed differences between Ctrl and LP. The lactic acid bacterial counts (log(10) cfu/g of wet silage) were 3.94 and 4.53 for the untreated and treated silage, respectively, at ensiling. The relative population size (RPS) of L. plantarum, determined by real-time PCR of 16S rRNA gene copies, was greater in LP compared with Ctrl. The ordination points corresponding to certain individual cows clustered separately, and the most distinctive bacterial communities were those associated with MFD cows. The RPS of Megasphaera elsdenii was greater in 1 of the 2 MFD cows, although mean RPS of M. elsdenii did not differ between the treatments. In addition to the differences in rumen BCC between LP and Ctrl, MFD cows also displayed differences in BCC compared with cows with normal milk fat yield.     

Feeding Value of Dry Corn,Ensiled High Moisture Corn,and Propionic Acid Treated High Moisture Corn Fed with Hay or Haylage for Lactating Dairy Cows

Trial 1. Fifty lactating Holstein and Brown Swiss cows were assigned to six groups in a 3 × 2 factorial design and fed one of six diets for 16 wk: (1) dry corn + hay, (2) dry corn + haylage, (3) ensiled high moisture corn + hay, (4) ensiled high moisture corn + haylage, (5) propionic acid treated corn + hay, and (6) propionic acid treated corn + haylage. Quantities equal in dry matter of dry corn, ensiled corn, and acid treated corn were offered in the ratio of 1 kg concentrate (corn and supplement) for each 2.75 kg milk produced. Forage was fed free choice. Means adjusted by covariance for cows fed diets 1 to 6 averaged: dry matter intake (kg/day), 16.7, 20.0, 17.4, 20.6, 17.1, 20.0; 4% fat-corrected milk (kg/day), 21.8, 21.1, 22.6, 23.5, 22.4, 23.4; milk fat percent, 3.54, 3.45, 3.63, 3.53, 3.62, 3.80; and acetate to propionate ratio 3.53, 3.85, 3.73, 3.66, 3.13, 3.32. Cows fed ensiled corn and acid treated corn produced more 4% fat-corrected milk than did cows fed dry corn. The molar percent acetate to propionate ratio in rumen fluid of cows fed acid treated corn was lower than for cows fed dry corn or ensiled corn.Trial 2. Dry corn or propionic acid treated corn was fed to 12 cows in combination with a supplement, 4.54 kg of hay, and ad libitum haylage. Means adjusted by covariance for cows fed dry corn and acid treated corn averaged: dry matter intake (kg/day), 18.2 and 17.7; 4% fat-corrected milk (kg/day), 20.6 and 20.1; and total digestible nutrients (%) 63.7 and 58.7.Any of these methods are acceptable for storing corn, and feeding this corn in properly supplemented diets will yield acceptable lactation performance.     

Differential response of ducks and chicks to dietary sorghum tannins

White Pekin ducklings were reared in floor pens and given access to nipple-type waterers in order to eliminate a feeding behaviour previously observed in battery brooder-raised ducks in which sorghum tannins were possibly detoxicated by exposure of the ground grain to water. High-tannin sorghum (HTS)—soya bean meal and low-tannin sorghum (LTS)—soya bean meal diets, suboptimal in protein, with or without supplemental methionine, and either in dry mash or pellet form, were fed to both day-old ducks and chicks for either 14 or 17 days, respectively. The chicks were reared in battery brooders. In contrast to previous findings with ducks raised in battery brooders, HTS-fed ducks reared in floor pens exhibited reduced weight gain and feed efficiency values compared with LTS-fed ducks. However, the magnitude of the growth depression caused by feeding ducks HTS versus LTS was much less than that observed in chicks fed the identical diets (17 versus 33%, respectively). Methionine supplementation of the HTS diets completely overcame the reduced weight gain in ducks, but feed efficiency values were still significantly poorer than those of ducks fed methionine-supplemented LTS diets. In contrast, although HTS-fed chicks responded to dietary methionine supplementation, they still exhibited poorer weight gain and feed eficiency values compared with birds fed LTS diets similarly supplemneted. Increasing the dietary level of supplemental methionine did not result in any further improvement in performance of chicks fed either LTS- or HTS-based diets. It was concluded that, compared with chicken, ducks are less affected by dietary sorghum tannins.