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M A Khan - One of the best experts on this subject based on the ideXlab platform.
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impact of weaning age on Rumen Development in artificially reared lambs1
Journal of Animal Science, 2019Co-Authors: M A Khan, Omar Cristobal Carballo, F W Knol, Sarah Lewis, David Robert Stevens, R A Laven, S A MccoardAbstract:This study examined the impact of weaning age (4 vs. 6 wk) on Rumen morphological and metabolic Development in artificially reared lambs. Thirty-two mixed-sex lambs (2 to 5 d old) were randomly allocated to 1 of 2 weaning groups: early weaning (EW; 4 wk) and control (Ctrl; 6 wk). Lambs were individually penned and fed milk replacer (MR; 24% CP and 25% fat, DM basis) at 20% of their corresponding initial BW. Weaning was achieved by gradual reduction of MR allowance over a period of 3 wk using a step-down procedure. Concentrate and meadow hay were offered ad libitum from 1 d of the study until 6 wk, when lambs were transferred to a mixed sward pasture. At week 4, individual DMI were recorded and blood samples collected to measure β-hydroxybutyrate (BHBA) and NEFA. Eight animals per group were euthanized at week 4 and 16 to evaluate short chain fatty acids (SCFA) and histomorphometry of the Rumen walls: dorsal (DS), ventral (VS), dorsal blind (DBS), and ventral blind (VBS) sacs. Linear mixed models were used to analyze the effect of weaning treatments at week 4 and 16, and to compare between timepoints and between Rumen sites. Dry matter intake and Rumen SCFA profiles were similar between groups (P > 0.10) at week 4 and 16. Plasma concentrations of BHBA were greater (P = 0.03) in EW than in Ctrl lambs, while NEFA did not differ (P > 0.10) between groups at week 4. No effect of weaning age on Rumen empty weight, and papillae density, length, width, surface area ratio, and muscle layer thickness at any of the 4 Rumen sites was found (P > 0.10) at either week 4 or week 16, except for greater (P = 0.02) papillae epithelium thickness in the DBS at week 4 in EW than Ctrl lambs. Papillae morphology and muscular thickness differed across Rumen sites at week 4 and week 16 (P 0.10). Rumen papillae length, width, and muscle layer thickness increased while papillae density and surface area ratio decreased (P < 0.05) between 4 and 16 wk. The results of this study indicate that morphological and physiological Development of the Rumen can be accelerated to support weaning of artificially reared lambs at 4 wk, using a step-down weaning system. Morphological differences between Rumen sacs denote that future studies in lambs evaluating the impact of different diets should involve representative sampling across the Rumen rather than a single site to more accurately study Rumen Development and ontogenic changes.
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effect of weaning age on growth mammary gland Development and immune function in holstein friesian calves fed conserved alfalfa fiberstart
Journal of Dairy Science, 2019Co-Authors: S A Mccoard, A Heiser, K Lowe, A J Molenaar, Paul S Maclean, P D Johnstone, S Leath, S O Hoskin, M A KhanAbstract:ABSTRACT This study aimed to evaluate intake, body growth, and the Development of the Rumen, mammary gland, and immune system in Holstein Friesian calves reared for 100 d on the commercially available feed FiberStart (conserved alfalfa, Medicago sativa; Fiber Fresh Feeds Ltd., Reporoa, New Zealand) and fed calf milk replacer (CMR) for either 56 or 91 d. Eighty calves (40 bulls and 40 heifer calves) were reared indoors in groups (n = 5 of the same sex/pen). All calves were fed 4 L of CMR/d (175 g/L of CMR) in 2 feeds/d for the first 10 d and then 1 feed/d until d 49 or 84. The calves were gradually weaned by d 56 (earlier weaned; n = 8 pens) and d 91 (later weaned; n = 8 pens). All calves were fed FiberStart ad libitum as the only solid feed source from d 1 to 100 of the study. Irrespective of treatment, all calves had similar body weights at d 0 (40.9 ± 3.0 kg) and d 49 (74.2 ± 5.1 kg) of the study. Calf sex had no effect on intake, growth, blood, and immune system parameters. Earlier-weaned calves consumed 18% more solid feed dry matter but had 16% lower body weight gain (28.9 vs. 38.5 kg, respectively) from d 56 to 100 relative to later-weaned calves, resulting in different body weight at 100 d (104 vs. 121 ± 1.3 kg). Although earlier-weaned calves could compensate for the loss of CMR dry matter and crude protein intake from d 56 to 100 by increasing forage intake, they were unable to compensate for the loss of energy from the CMR by increasing solid feed consumption. Plasma β-hydroxybutyrate concentrations were 52% greater in earlier-weaned calves than in later-weaned calves at d 84, indicating greater metabolic activity of the Rumen wall. The duration of CMR feeding had no influence on humoral or cell-mediated immune functions of the calves, as evidenced by a lack of effect on antivaccine antibody responses as well as on immune gene expression. Earlier- versus later-weaned heifer calves had 5% lower mammary gland mass, indicating that greater energy supply increased mammary mass. The results of this experiment demonstrate the ability to artificially rear dairy calves on a conserved alfalfa as the only solid feed. Furthermore, earlier weaning off CMR promotes solid feed intake and an associated increase in blood β-hydroxybutyrate, an indicator of Rumen Development, but increasing the duration of CMR feeding improves growth and mammary gland mass by d 100. The implications of these findings on lifetime growth, health, and milk production in dairy heifers warrant further investigation.
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invited review transitioning from milk to solid feed in dairy heifers
Journal of Dairy Science, 2016Co-Authors: M A Khan, Daniel M. Weary, A Bach, Marina A. G. Von KeyserlingkAbstract:Calves are born with a physically and metabolically underdeveloped Rumen and initially rely on milk to meet nutrient demands for maintenance and growth. Initiation of solid feed consumption, acquisition of anaerobic microbes, establishment of Rumen fermentation, expansion of Rumen in volume, differentiation and growth of papillae, Development of absorption and metabolic pathways, maturation of salivary apparatus and Development of rumination behavior are all needed as the calf shifts from dependence on milk to solid feed. In nature and some production systems (e.g., most beef calves), young ruminants obtain nutrients from milk and fresh forages. In intensive dairying, calves are typically fed restricted amounts of milk and weaned onto starter feeds. Here we review the empirical work on the role of feeding and management during the transition from milk to solid feed in establishing the Rumen ecosystem, Rumen fermentation, Rumen Development, rumination behavior, and growth of dairy calves. In recent years, several studies have illustrated the benefits of feeding more milk and group rearing of dairy calves to take advantage of social facilitation (e.g., housing with peers or dam), and this review also examines the role of solid feed on Rumen Development and growth of calves fed large quantities of milk and reared under different housing situations. We conclude that the provision of high-starch and low-fiber starter feeds may negatively affect Rumen Development and that forage supplementation is beneficial for promoting Development of the gut and rumination behavior in young calves. It is important to note that both the physical form of starter diets and their nutritional composition affect various aspects of Development in calves. Further research is warranted to identify an optimal balance between physically effective fiber and readily degradable carbohydrates in starter diets to support Development of a healthy gut and Rumen, rumination behavior, and growth in young calves.
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hay intake improves performance and Rumen Development of calves fed higher quantities of milk
Journal of Dairy Science, 2011Co-Authors: M A Khan, Daniel M. Weary, Marina A. G. Von KeyserlingkAbstract:Research to date has suggested that access to forage before weaning can limit Rumen Development in calves, but no research has yet addressed the role of forage for calves fed higher quantities of milk. This study compared performance and Rumen Development of calves provided high volumes (equivalent to approximately 20% of calf birth weight) of milk with and without access to hay. At d 3 of age, individually housed calves were randomly assigned to treatment (either ad libitum access to chopped grass hay or no forage; n=15 calves per treatment, 10 heifers, and 5 bulls). All calves were provided ad libitum access to water and starter throughout the study. All calves were offered 8L of milk/d from a nipple bottle from d 3 to 35, 4 L/d from d 36 to 53, and 2L/d until weaning at d 56. Solid feed intake and growth parameters were monitored from d 3 to 70. At d 70, males from both treatments were slaughtered to measure Rumen Development parameters. Overall dry matter (DM) intake from solid feed did not differ between treatments before wk 5. However, during wk 6 to 10, calves fed forage consumed more total DM (starter plus hay) than did calves fed no forage. Hip and wither height, heart girth, and body barrel at d 3, 56, and 70 did not differ between treatments. ReticuloRumen weight was heavier in calves fed hay versus those fed only starter (12.77±1.29 vs. 7.99±0.69 kg with digesta; 1.89±0.05 vs.1.60±0.09 kg without digesta). Body weight without digesta was similar in calves fed forage or no forage. Mean Rumen pH was higher in calves fed hay compared with those fed no forage (5.49±0.08 vs. 5.06±0.04). In conclusion, provision of chopped hay to calves fed high volumes of milk can promote solid feed DM intake and Rumen Development without affecting BW gain.
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starch source evaluation in calf starter ii ruminal parameters Rumen Development nutrient digestibilities and nitrogen utilization in holstein calves
Journal of Dairy Science, 2008Co-Authors: M A Khan, S B Park, K S Baek, J K Ha, Yunjaie ChoiAbstract:Abstract Ruminal parameters, Rumen Development, nutrient digestibilities, and N utilization were estimated in Holstein calves fed starch from different sources. Ground corn, ground barley, ground wheat, and crimped oats were used to formulate 4 isostarch (25% of starter dry matter) pelleted diets. These diets were randomly allocated to calves (16 calves per treatment, 8 female and 8 male) and fed ad libitum along with mixed grass hay throughout the experiment. Ruminal contents and blood were sampled at d 35, 50, and 70 of age to estimate ruminal parameters and plasma β -hydroxybutyrate, respectively. At d 70, twenty-four male calves (6/treatment) were randomly selected, euthanized, and forestomach weight, papillae length (PL), papillae width (PW), Rumen wall thickness (RWT), and papillae concentration were measured. At d 63, twenty-four female calves (6/treatment) were randomly selected and moved to metabolism stalls to estimate total tract apparent nutrient digestibilities and N utilization. Female calves were given 2 wk for adaptation to experimental facilities and then total collections of feces and urine were made from d 77 to 84 of age. Ruminal pH at d 35 of age was higher in calves fed corn and oat diets than in those fed barley and wheat diets. Ruminal pH at d 50 and 70 of age was the lowest in calves on barley diets followed by those on oat and wheat diets and then by those on the corn diet. Ruminal total volatile fatty acid concentrations at d 35 of age were greatest in calves fed corn or wheat diets followed by those fed barley and oat diets. Calves on corn and wheat diets maintained greater ruminal volatile fatty acids concentrations at d 50 and 70 of age. Ruminal ammonia, acetate, propionate, butyrate, and blood β-hydroxybutyrate concentrations were also greater in calves on the corn and wheat diets. Full and empty weights of forestomach, PL, PW, RWT, and papillae concentrations were greater in calves on corn and wheat diets. Daily average intake of nutrients (dry matter, crude protein, neutral detergent fiber, starch, Ca, and P) was greater in calves fed corn and wheat diets than in those fed barley and oat diets. Starch source did not influence the total tract apparent digestibilities of nutrients in calves. Daily N retention (g/d) was greatest on the corn diet followed by the wheat diet and then the barley and oat diets. In conclusion, calves on a corn diet have greater ruminal capacity to accommodate feed bulk. More physically and metabolically functional Rumens in calves on corn and wheat diets probably resulted in greater feed consumption and N retention.
Yunjaie Choi - One of the best experts on this subject based on the ideXlab platform.
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starch source evaluation in calf starter ii ruminal parameters Rumen Development nutrient digestibilities and nitrogen utilization in holstein calves
Journal of Dairy Science, 2008Co-Authors: M A Khan, S B Park, K S Baek, J K Ha, Yunjaie ChoiAbstract:Abstract Ruminal parameters, Rumen Development, nutrient digestibilities, and N utilization were estimated in Holstein calves fed starch from different sources. Ground corn, ground barley, ground wheat, and crimped oats were used to formulate 4 isostarch (25% of starter dry matter) pelleted diets. These diets were randomly allocated to calves (16 calves per treatment, 8 female and 8 male) and fed ad libitum along with mixed grass hay throughout the experiment. Ruminal contents and blood were sampled at d 35, 50, and 70 of age to estimate ruminal parameters and plasma β -hydroxybutyrate, respectively. At d 70, twenty-four male calves (6/treatment) were randomly selected, euthanized, and forestomach weight, papillae length (PL), papillae width (PW), Rumen wall thickness (RWT), and papillae concentration were measured. At d 63, twenty-four female calves (6/treatment) were randomly selected and moved to metabolism stalls to estimate total tract apparent nutrient digestibilities and N utilization. Female calves were given 2 wk for adaptation to experimental facilities and then total collections of feces and urine were made from d 77 to 84 of age. Ruminal pH at d 35 of age was higher in calves fed corn and oat diets than in those fed barley and wheat diets. Ruminal pH at d 50 and 70 of age was the lowest in calves on barley diets followed by those on oat and wheat diets and then by those on the corn diet. Ruminal total volatile fatty acid concentrations at d 35 of age were greatest in calves fed corn or wheat diets followed by those fed barley and oat diets. Calves on corn and wheat diets maintained greater ruminal volatile fatty acids concentrations at d 50 and 70 of age. Ruminal ammonia, acetate, propionate, butyrate, and blood β-hydroxybutyrate concentrations were also greater in calves on the corn and wheat diets. Full and empty weights of forestomach, PL, PW, RWT, and papillae concentrations were greater in calves on corn and wheat diets. Daily average intake of nutrients (dry matter, crude protein, neutral detergent fiber, starch, Ca, and P) was greater in calves fed corn and wheat diets than in those fed barley and oat diets. Starch source did not influence the total tract apparent digestibilities of nutrients in calves. Daily N retention (g/d) was greatest on the corn diet followed by the wheat diet and then the barley and oat diets. In conclusion, calves on a corn diet have greater ruminal capacity to accommodate feed bulk. More physically and metabolically functional Rumens in calves on corn and wheat diets probably resulted in greater feed consumption and N retention.
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starch source evaluation in calf starter ii ruminal parameters Rumen Development nutrient digestibilities and nitrogen utilization in holstein calves
Journal of Dairy Science, 2008Co-Authors: M A Khan, S B Park, K S Baek, H J Lee, W S Lee, H S Kim, S B Kim, Yunjaie ChoiAbstract:Ruminal parameters, Rumen Development, nutrient digestibilities, and N utilization were estimated in Holstein calves fed starch from different sources. Ground corn, ground barley, ground wheat, and crimped oats were used to formulate 4 isostarch (25% of starter dry matter) pelleted diets. These diets were randomly allocated to calves (16 calves per treatment, 8 female and 8 male) and fed ad libitum along with mixed grass hay throughout the experiment. Ruminal contents and blood were sampled at d 35, 50, and 70 of age to estimate ruminal parameters and plasma beta-hydroxybutyrate, respectively. At d 70, twenty-four male calves (6/treatment) were randomly selected, euthanized, and forestomach weight, papillae length (PL), papillae width (PW), Rumen wall thickness (RWT), and papillae concentration were measured. At d 63, twenty-four female calves (6/treatment) were randomly selected and moved to metabolism stalls to estimate total tract apparent nutrient digestibilities and N utilization. Female calves were given 2 wk for adaptation to experimental facilities and then total collections of feces and urine were made from d 77 to 84 of age. Ruminal pH at d 35 of age was higher in calves fed corn and oat diets than in those fed barley and wheat diets. Ruminal pH at d 50 and 70 of age was the lowest in calves on barley diets followed by those on oat and wheat diets and then by those on the corn diet. Ruminal total volatile fatty acid concentrations at d 35 of age were greatest in calves fed corn or wheat diets followed by those fed barley and oat diets. Calves on corn and wheat diets maintained greater ruminal volatile fatty acids concentrations at d 50 and 70 of age. Ruminal ammonia, acetate, propionate, butyrate, and blood beta-hydroxybutyrate concentrations were also greater in calves on the corn and wheat diets. Full and empty weights of forestomach, PL, PW, RWT, and papillae concentrations were greater in calves on corn and wheat diets. Daily average intake of nutrients (dry matter, crude protein, neutral detergent fiber, starch, Ca, and P) was greater in calves fed corn and wheat diets than in those fed barley and oat diets. Starch source did not influence the total tract apparent digestibilities of nutrients in calves. Daily N retention (g/d) was greatest on the corn diet followed by the wheat diet and then the barley and oat diets. In conclusion, calves on a corn diet have greater ruminal capacity to accommodate feed bulk. More physically and metabolically functional Rumens in calves on corn and wheat diets probably resulted in greater feed consumption and N retention.
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structural growth Rumen Development and metabolic and immune responses of holstein male calves fed milk through step down and conventional methods
Journal of Dairy Science, 2007Co-Authors: M A Khan, H J Lee, W S Lee, Hasuck Kim, T Y Hur, Gukhyun Suh, S J Kang, Yunjaie ChoiAbstract:Abstract Structural growth, feed consumption, Rumen Development, metabolic response, and immune response were studied in Holstein calves fed milk through either a conventional method or a step-down (STEP) method. In the conventional method, calves (n = 20) were fed colostrum and then milk at a rate of 10% of their BW for the entire period of 44 d. In the STEP method, calves (n = 20) were given colostrum and then milk at a rate of 20% of their BW for 23 d, which was reduced (between d 24 to 28) to 10% of their BW for the remaining 16 d. The calves on both methods were weaned gradually by diluting milk with water between d 45 and 49. After weaning, feed consumption, structural growth, and body weight gain were monitored until calves were 63 d of age. At d 63, twelve calves (6/treatment) were euthanized and Rumen papillae length, papillae width, Rumen wall thickness, and emptied forestomach weight were recorded. At wk 4, 7, and 9, ruminal contents were collected to enumerate Rumen metabolites. The STEP-fed calves consumed a greater amount of milk than conventionally fed calves during the pre-STEP (d 1 to 28), post-STEP (d 29 to 49), and preweaning (d 1 to 49) periods. Consumption of starter and hay was greater during the pre-STEP period and lesser during the post-STEP and postweaning (d 50 to 63) periods in calves on the conventional method than on the STEP method. Body weight gain and structural growth measurements of calves were greater on the STEP method than on the conventional method. A hypophagic condition caused by greater milk consumption depressed solid feed intake of STEP-fed calves during the pre-STEP period, and a hyperphagic response caused by a reduced nutrient supply from milk triggered their consumption of solid feed during the post-STEP and postweaning periods. Ruminal pH and concentrations of ammonia, total volatile fatty acids, acetate, propionate, butyrate, and plasma β -hydroxybutyrate were higher in calves on the STEP method and at weaning and postweaning (d 63) were lower in calves on the conventional method. Emptied weight of the forestomach, Rumen wall thickness, papillae length, papillae width, and papillae concentration were higher in calves on the STEP method than in those on the conventional method. Blood glucose was lower, and blood urea nitrogen and β -hydroxybutyrate at weaning and postweaning were higher in STEP-fed calves. Serum IgG, IgA, and triglycerides for 1, 2, and 3 wk of age were higher in calves on the STEP method than in those on the conventional method. In conclusion, greater feed consumption, BW gain, and structural growth, and a more metabolically and physically developed Rumen were observed in calves on the STEP method than in those on the conventional method.
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structural growth Rumen Development and metabolic and immune responses of holstein male calves fed milk through step down and conventional methods
Journal of Dairy Science, 2007Co-Authors: M A Khan, H J Lee, W S Lee, Hasuck Kim, T Y Hur, Gukhyun Suh, S J Kang, Yunjaie ChoiAbstract:Structural growth, feed consumption, Rumen Development, metabolic response, and immune response were studied in Holstein calves fed milk through either a conventional method or a step-down (STEP) method. In the conventional method, calves (n = 20) were fed colostrum and then milk at a rate of 10% of their BW for the entire period of 44 d. In the STEP method, calves (n = 20) were given colostrum and then milk at a rate of 20% of their BW for 23 d, which was reduced (between d 24 to 28) to 10% of their BW for the remaining 16 d. The calves on both methods were weaned gradually by diluting milk with water between d 45 and 49. After weaning, feed consumption, structural growth, and body weight gain were monitored until calves were 63 d of age. At d 63, twelve calves (6/treatment) were euthanized and Rumen papillae length, papillae width, Rumen wall thickness, and emptied forestomach weight were recorded. At wk 4, 7, and 9, ruminal contents were collected to enumerate Rumen metabolites. The STEP-fed calves consumed a greater amount of milk than conventionally fed calves during the pre-STEP (d 1 to 28), post-STEP (d 29 to 49), and preweaning (d 1 to 49) periods. Consumption of starter and hay was greater during the pre-STEP period and lesser during the post-STEP and postweaning (d 50 to 63) periods in calves on the conventional method than on the STEP method. Body weight gain and structural growth measurements of calves were greater on the STEP method than on the conventional method. A hypophagic condition caused by greater milk consumption depressed solid feed intake of STEP-fed calves during the pre-STEP period, and a hyperphagic response caused by a reduced nutrient supply from milk triggered their consumption of solid feed during the post-STEP and postweaning periods. Ruminal pH and concentrations of ammonia, total volatile fatty acids, acetate, propionate, butyrate, and plasma beta-hydroxybutyrate were higher in calves on the STEP method and at weaning and postweaning (d 63) were lower in calves on the conventional method. Emptied weight of the forestomach, Rumen wall thickness, papillae length, papillae width, and papillae concentration were higher in calves on the STEP method than in those on the conventional method. Blood glucose was lower, and blood urea nitrogen and beta-hydroxybutyrate at weaning and postweaning were higher in STEP-fed calves. Serum IgG, IgA, and triglycerides for 1, 2, and 3 wk of age were higher in calves on the STEP method than in those on the conventional method. In conclusion, greater feed consumption, BW gain, and structural growth, and a more metabolically and physically developed Rumen were observed in calves on the STEP method than in those on the conventional method.
A J Heinrichs - One of the best experts on this subject based on the ideXlab platform.
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straw particle size in calf starters effects on digestive system Development and Rumen fermentation
Journal of Dairy Science, 2016Co-Authors: F X Suarezmena, A J Heinrichs, C M Jones, T M Hill, J D QuigleyAbstract:Two trials were conducted to determine effects of straw particle size in calf starter on Rumen fermentation and Development in calves. Holstein calves (n=17 in trial 1; n=25 in trial 2) were housed in individual pens; bedding (wood shavings) was covered with landscape fabric to completely avoid consumption of bedding. Milk replacer was fed at 12% of birth body weight per day and water offered free choice. Calves were randomly assigned to 4 treatments differing in geometric mean particle length (Xgm) of straw comprising 5% of starter dry matter. Straw was provided within the pellet at manufacture (PS; 0.82 mm Xgm) or mixed with the pellet at time of feeding at Xgm of 3.04 (SS), 7.10 (MS), or 12.7 (LS) mm. Calves (n=12; 3/treatment) in trial 1 were fitted with a Rumen cannula by wk 2 of age. A fixed amount of starter that was adjusted with age and orts were fed through the cannula in cannulated calves. Calves were euthanized 6 wk after starter was offered (9 and 7 wk of age for trials 1 and 2, respectively). Rumen digesta pH linearly decreased with age, whereas volatile fatty acid concentration increased with age. Overall pH had a cubic trend with SS lower than that of PS and MS. Molar proportion of acetate decreased with age whereas propionate proportion increased. Overall molar proportions of volatile fatty acids were not affected by diet. Fecal Xgm was not different in spite of changes in diet particle size and Rumen digesta of PS being greater than SS, MS, and LS at slaughter. Fecal pH and starch concentration were not affected by diet; however, pH decreased whereas starch content increased with age. Weight of stomach compartments, Rumen papillae length and width, and Rumen wall thickness did not differ between diets. Omasum weight as a percentage of body weight at harvest linearly decreased as straw particle size increased. Under the conditions of this study, modifying straw particle length in starter grain resulted in minimal Rumen fermentation parameter changes and no changes in Rumen Development. Rumen pH and fermentation changes with age were likely effects of increasing starter intake.
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effects of including corn distillers dried grains with solubles in dairy calf feeds
Journal of Dairy Science, 2011Co-Authors: F X Suarezmena, A J Heinrichs, T M Hill, H G Bateman, J M Aldrich, R L SchlotterbeckAbstract:Abstract A series of 5 trials was conducted to determine the effect of distillers dried grains with solubles (DG) in calf diets. Trial 1 compared 0 or 49% DG in 18% crude protein (CP) starters (as-fed basis) fed to calves initially 2 to 3 d old for 56 d. Digestibility was estimated during d 52 to 56 using chromic oxide. Trial 2 compared 0 or 39% DG in 16% CP growers fed to calves from 8 to 12 wk of age from 28 d. Trial 3 compared 0, 10, or 20% DG in 18% CP starters fed to calves initially 2 to 3 d old for 56 d. Trial 4 compared 0 or 20% DG in 16% CP growers fed to calves from 8 to 12 wk of age from 28 d. As DG increased in all diets, acid detergent fiber, neutral detergent fiber, and fat increased and calculated metabolizable energy was similar but not equalized. In trials 1 and 3, calves (n=48/trial) housed in individual pens were fed 26% CP, 17% fat milk replacer powder and weaned at 28 d. Trials 2 and 4 used calves (n=48/trial) housed in group pens (6 calves/pen) that had been weaned for 28 d before the trials' start. Trial 5 (n=18 calves) had the same starter treatments as trial 3 fed in combination with high or low milk replacer intake, with calves killed at 35 d to determine effects of DG and milk replacer intake on Rumen Development. In trial 1, average daily gain (ADG) was 6% greater and dry matter digestibility was 10% greater for calves fed 0% versus 49% DG. In trial 2, ADG (9%), feed efficiency (10%), and hip width change (19%) were greater for calves fed 0% versus 39% DG. Performance measures did not differ among starter treatments in Trials 3 and 5. In trial 4, ADG (4%), feed efficiency (5%), and hip width change (19%) were greater for calves fed 0% versus 20% DG. In trial 5, Rumen Development was not affected by DG inclusion, but was greater for calves fed milk replacer at 630 versus 940g/d, which had greater starter intake. Overall, we conclude that high levels of distillers in calf starters and growers decrease growth of calves; however, starters with ≤20% DG allow for normal growth rates and Rumen Development.
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effects of weaning age and milk feeding frequency on dairy calf growth health and Rumen parameters
Livestock Science, 2007Co-Authors: S I Kehoe, Chad Daniel Dechow, A J HeinrichsAbstract:Abstract Various methods can be used to feed dairy calves that may influence calf performance and these include changing frequency of feeding or age at weaning. Two trials were conducted to determine effects of feeding frequency and weaning age on calf growth, health and Rumen Development, where 124 Holstein heifer and bull calves were weaned at 3, 4, 5 or 6 weeks of age. During Trial 1, milk replacer (12.5% DM; 22% CP, 15.6% fat) was fed at 10% BW twice per day until 1 week prior to weaning when intake was reduced to 5% BW. During Trial 2 calves were fed at 10% BW in two feedings until 14 days, then at 10% BW once daily until 1 week prior to weaning when milk replacer was reduced to 5% BW. Blood glucose and urea nitrogen, BW 4 h post-feeding, heart girth, hip height, and withers height 4 h post-feeding were obtained weekly. Growth and structural measurements were similar for all treatments up to 8 weeks of age in both trials. Blood constituents and health observations were not different between trials. Similar growth and performance between treatments in both trials through 8 weeks of age indicate that calf performance is not affected by weaning early and feeding once daily.
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case study effects of amylase on Rumen Development in neonatal dairy calves1
The Professional Animal Scientist, 2007Co-Authors: A J Heinrichs, S I Kehoe, A M Gehman, C M Jones, J M TricaricoAbstract:ABSTRACT Two trials, each with 15 male Holstein calves, were conducted to determine whether the addition of amylase to calf starter could affect Rumen Development and calf performance. Amylase was added to calf starter at a rate of 0, 6, or 12 g/d, fed in the first 200 g of grain consumed each day. Grain and milk intake, fecal scores, and health were monitored daily. Body weight, hip width, heart girth, withers height, and blood β-hydroxybutyrate were measured weekly 4 h after morning feeding. ReticuloRumens were harvested at 35 d in Trial 1 and at 42 d in Trial 2. Rumen tissue growth was measured in 9 sampling areas for papillae length and width and Rumen wall thickness. Amylase activity differed between trials; calves in Trial 1 were fed 0, 6,762, or 13,524 dextrinizing units (DU)/d, and in Trial 2 calves were fed 0, 4,710, or 9,420 DU/d. No differences were detected in calf health, growth, grain intake, or blood levels of β-hydroxybutyrate. Rumen Development results from these 2 trials suggest that amylase moderately enhanced Rumen tissue growth when fed in calf starter. In the first trial 6,762 DU/d was more effective than 13,524 DU/d, and in the second trial 9,420 DU/d tended to be more effective than 4,710 DU/d. When combined, these results suggest that an adequate level of amylase to affect Rumen tissue growth may lie between 6,762 and 9,420 DU/d.
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Rumen Development in the dairy calf.
2005Co-Authors: A J Heinrichs, K E Lesmeister, P. C. GarnsworthyAbstract:The degradation of feedstuffs, Rumen microbial synthesis, and the various resulting end products have been a subject of investigation for over a century. In 1884, Tappiener (as cited in Phillipson, 1947) attributed cellulose digestion in the Rumen to digestive actions of symbiotic organisms in the Rumen. Much work followed these early discoveries, devoted primarily to describing the digestion of cellulose, the assimilation of various end products of the microbial population, and the various species of Rumen bacteria that exist under certain Rumen conditions.
K E Lesmeister - One of the best experts on this subject based on the ideXlab platform.
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Rumen Development in the dairy calf.
2005Co-Authors: A J Heinrichs, K E Lesmeister, P. C. GarnsworthyAbstract:The degradation of feedstuffs, Rumen microbial synthesis, and the various resulting end products have been a subject of investigation for over a century. In 1884, Tappiener (as cited in Phillipson, 1947) attributed cellulose digestion in the Rumen to digestive actions of symbiotic organisms in the Rumen. Much work followed these early discoveries, devoted primarily to describing the digestion of cellulose, the assimilation of various end products of the microbial population, and the various species of Rumen bacteria that exist under certain Rumen conditions.
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effects of adding extra molasses to a texturized calf starter on Rumen Development growth characteristics and blood parameters in neonatal dairy calves
Journal of Dairy Science, 2005Co-Authors: K E Lesmeister, A J HeinrichsAbstract:A texturized calf starter containing 5 (control) or 12% molasses [on a dry matter (DM) basis] was fed to dairy calves to determine effects on intake, growth, blood parameters, and Rumen Development. Forty-six Holstein calves (26 male and 20 female) were started at 2 +/- 1 d of age and studied for 42 d. Starter DM intake was measured and fecal scoring was conducted daily. Growth and blood parameter measurements were conducted weekly. A subset of 6 male calves (3 per treatment) was euthanized at 4 wk of age, and Rumen tissue sampled for Rumen epithelial growth measurements. Starter sugar content was significantly increased in the starter containing extra molasses. Postweaning and overall starter DM intake, overall total DM intake, daily heart girth change, and final heart girth were significantly decreased, whereas overall average daily gain tended to decrease when calves received starter containing 12% molasses. However, blood volatile fatty acid concentrations were significantly increased when calves received a starter containing 12% molasses. No significant differences were observed between calves receiving starters containing 5 or 12% molasses for all other variables. The data indicates that adding extra molasses to a texturized calf starter decreases intake and structural growth, possibly causing decreased weight gain, but increases blood volatile fatty acid concentrations and slightly increases ruminal Development. However, feed handling and physical prehension problems in addition to the negative influences on calf growth and intake do not support increasing starter molasses content to 12% of the supplement.
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effects of corn processing on growth characteristics Rumen Development and Rumen parameters in neonatal dairy calves
Journal of Dairy Science, 2004Co-Authors: K E Lesmeister, A J HeinrichsAbstract:Neonatal Holstein calves were fed texturized calf starters containing 33% whole (WC), dry-rolled (DRC), roasted-rolled (RC), or steam-flaked (SFC) corn to investigate how corn processing method affects intake, growth, Rumen and blood metabolites, and Rumen Development. In the first experiment, 92 Holstein calves (52 male and 40 female) were started at 2 +/- 1 d of age and studied for 42 d. Starter dry matter (DM) intake was measured and fecal scoring conducted daily. Growth and blood parameter measurements were conducted weekly. A subset of 12 male calves (3/treatment) was euthanized at 4 wk of age and Rumen tissue sampled for Rumen epithelial Development measurements. Experiment 2 consisted of 12 male Holstein calves ruminally cannulated at 7 +/- 1 d of age. Rumen fluid and blood samples were collected during wk 2 to 6. In the first experiment, postweaning and overall starter and total DM intake were significantly higher in calves fed starter with DRC than RC or SFC. Postweaning and overall starter and total DM intake were significantly higher in calves fed starter with WC than SFC. Postweaning average daily gain was significantly greater in calves fed starter with DRC than SFC. Blood volatile fatty acid concentrations were significantly higher in calves fed starter with SFC than in calves fed all other treatments. Papillae length and Rumen wall thickness at 4 wk were significantly greater in calves fed starter with SFC than DRC and WC, respectively. In experiment 2, calves fed starter with WC had higher Rumen pH and lower Rumen volatile fatty acid concentrations than calves fed all other starters. Rumen propionate production was increased in calves receiving starter with SFC; however, Rumen butyrate production was higher in calves fed starter with RC. Results indicate that the type of processed corn incorporated into calf starter can influence intake, growth, and Rumen parameters in neonatal calves. Calves consuming starter containing RC had similar body weight, feed efficiency, and Rumen Development but increased structural growth and ruminal butyrate production when compared with the other corn processing treatments.
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effects of supplemental yeast saccharomyces cerevisiae culture on Rumen Development growth characteristics and blood parameters in neonatal dairy calves
Journal of Dairy Science, 2004Co-Authors: K E Lesmeister, A J Heinrichs, M T GablerAbstract:Yeast (Saccharomyces cerevisiae) culture was added to a texturized calf starter at 0 (control), 1, or 2% of dry matter to determine effects on intake, growth, blood parameters, and Rumen Development. Seventy-five Holstein calves (38 male; 37 female) were started on the experiment at 2 ± 1 d of age and were studied for 42 d. Starter intake was measured, and fecal scoring was conducted daily. Growth and blood parameter measurements were recorded at weekly intervals. A subset of 6 male calves (2 per treatment) was euthanized at 5 wk of age, and Rumen tissue was sampled for Rumen epithelial growth measurements. An additional 6 male calves were euthanized at 6 wk of age for Rumen epithelial growth measurements. Inclusion of yeast culture at 2% of the starter ration significantly increased starter and total dry matter intake, average daily gain, and daily hip width change when compared with the control treatment. Average daily gain was improved by 15.6% for the 2% yeast treatment. Daily change in hip height was also significantly greater for calves receiving 2% supplemental yeast culture than for calves receiving 1%. No significant treatment differences were observed for any other variables. These data suggest that the addition of yeast culture in a dairy calf starter at 2% enhances dry matter intake and growth and slightly improves Rumen Development in dairy calves.
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Development and analysis of a Rumen tissue sampling procedure
Journal of Dairy Science, 2004Co-Authors: K E Lesmeister, Peter R. Tozer, A J HeinrichsAbstract:Abstract A procedure for Rumen tissue sampling was developed to determine treatment effects on Rumen Development and papillae growth in young calves and to improve repeatability in Rumen tissue sampling techniques. Rumens were collected from 42 male Holstein calves from 4 separate experiments. Rumen sampling areas (n = 9) included the caudal dorsal blind sac, cranial dorsal sac, cranial ventral sac, and the caudal and ventral portions of the caudal ventral blind sac. Right and left sides of the Rumen were sampled. Five 1-cm 2 sections were removed from each area and measured for papillae length (n = 20/area), papillae width (n = 20/area), Rumen wall thickness (n = 5/area), and number of papillae per cm 2 (n = 5/area). Correlations between areas, samples, and measurements were obtained, and comparisons between experiments, areas, samples, and measurements were performed for all variables. In addition, power analyses were conducted for all variables to determine the efficacy of the procedure in detecting treatment differences. Results indicate that samples should be taken from the caudal and cranial sacs of the dorsal and ventral Rumen to sufficiently represent papillae growth and Development throughout the entire Rumen. The procedure is capable of detecting treatment differences for papillae length and papillae width, has a decreased but acceptable capability of detecting treatment differences for Rumen wall thickness, but appears limited in ability to detect treatment differences for papillae per square centimeter. In conclusion, Rumen tissue sampling to determine extent of Rumen Development in calves can be performed in a nonbiased and repeatable manner utilizing a limited number of calves.
W J J Gerrits - One of the best experts on this subject based on the ideXlab platform.
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chopped or long roughage what do calves prefer using cross point analysis of double demand functions
PLOS ONE, 2014Co-Authors: L E Webb, B Engel, W J J Gerrits, Margit Bak Jensen, Cornelis G Van Reenen, Imke J M De Boer, E A M BokkersAbstract:The present study aimed to quantify calves'(Bos taurus) preference for long versus chopped hay and straw, and hay versus straw, using cross point analysis of double demand functions, in a context where energy intake was not a limiting factor. Nine calves, fed milk replacer and concentrate, were trained to work for roughage rewards from two simultaneously available panels. The cost (number of muzzle presses) required on the panels varied in each session (left panel/right panel): 7/35, 14/28, 21/21, 28/14, 35/7. Demand functions were estimated from the proportion of rewards achieved on one panel relative to the total number of rewards achieved in one session. Cross points (cp) were calculated as the cost at which an equal number of rewards was achieved from both panels. The deviation of the cp from the midpoint (here 21) indicates the strength of the preference. Calves showed a preference for long versus chopped hay (cp = 14.5; P = 0.004), and for hay versus straw (cp = 38.9; P = 0.004), both of which improve Rumen function. Long hay may stimulate chewing more than chopped hay, and the preference for hay versus straw could be related to hedonic characteristics. No preference was found for chopped versus long straw (cp = 20.8; P = 0.910). These results could be used to improve the welfare of calves in production systems; for example, in systems where calves are fed hay along with high energy concentrate, providing long hay instead of chopped could promote roughage intake, Rumen Development, and rumination.
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effects of early Rumen Development and solid feed composition on growth performance and abomasal health in veal calves
Journal of Dairy Science, 2012Co-Authors: H Berends, Norbert Stockhofezurwieden, C G Van Reenen, W J J GerritsAbstract:Abstract The experiment was designed to study the importance of early Rumen Development and of the composition of solid feed intake on growth performance and abomasal health in milk-fed veal calves. One hundred and six Holstein-Friesian male calves were included in the experiment, and studied during 2 successive 12-wk periods (period 1 and period 2). In a 2 × 2 factorial arrangement, effects of partially replacing milk replacer by solid feed during period 1 and partially replacing dry matter (DM) intake from maize silage and barley straw by concentrate during period 2 were tested. Solid feed during period 1 consisted of maize silage, barley straw, and concentrate (25:25:50 on a DM basis). Solid feed during period 2 consisted of maize silage and barley straw (50:50 ratio on DM basis) for the nonconcentrate groups, and maize silage, barley straw and concentrates (25:25:50 on a DM basis) for the concentrate groups. At the end of period 1 (n=16) and at the end of period 2 (n=90), parameters of animal performance, Rumen Development, Rumen fermentation, ruminal drinking, and abomasal damage were examined. Partially replacing milk replacer by solid feed during period 1 resulted in early Rumen Development (ERD) at the end of period 1, characterized by increased Rumen weight, and an increased epithelial and absorptive surface area. Both ERD and partially replacing roughage by concentrates in period 2 increased the Rumen Development score at the end of period 2. Although ERD calves consumed more solid feed and less milk replacer during period 1 and 2 than non-ERD calves, carcass weight gains at 25wk were identical, and utilization of the solid feed provided appeared similar to that of milk replacer. Partially replacing roughage by concentrates in period 2 increased dressing percentage and warm carcass weight. Plaque formation at the Rumen mucosa was unaffected by ERD or partially replacing roughage by concentrates and generally low in all calves. The prevalence of large scars in the abomasum in ERD calves was decreased compared with non-ERD calves. This may indicate that ERD provided protection against abomasal lesions. In conclusion, early compared with late Rumen Development improves feed utilization and may be beneficial for abomasal health.
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effect of roughage source and roughage to concentrate ratio on animal performance and Rumen Development in veal calves
Journal of Dairy Science, 2007Co-Authors: B.j. Suárez, N Stockhofe, C G Van Reenen, J Dijkstra, W J J GerritsAbstract:Sixty-four male Holstein-Friesian x Dutch Friesian veal calves (46 ± 3.0 kg) were used to evaluate the effect of the inclusion of different levels and sources of dietary roughage on animal performance and Rumen Development. Treatments consisted of 1) C100 = concentrate only; 2) C70-S30 = concentrate (70%) with straw (30%), 3) C70-G30 = concentrate (70%) with dried grass (30%), 4) C70-G15-S15 = concentrate (70%) with dried grass (15%) and straw (15%), 5) C70-CS30 = concentrate (70%) with corn silage (30%), 6) C40-CS60 = concentrate (40%) with corn silage (60%), 7) C70-CS30-AL = concentrate (70%) with corn silage (30%) ad libitum, 8) C70-G15-S15-AL = concentrate (70%) with dried grass (15%) and straw (15%) ad libitum. All dietary treatments were provided in addition to a commercial milk replacer. Concentrate was provided as pellets and roughage was chopped. The dietary treatments 1 to 6 were supplied restrictedly to a maximum of 750 g of dry matter (DM) per day, whereas treatments 7 and 8 were offered ad libitum in combination with a reduced amount of milk replacer. Calves were euthanized after 10 wk. Straw supplementation (C70-S30 vs. C70-G30 and C70-CS30) reduced DM intake, and ad libitum supply of concentrate and roughage increased DM intake. Roughage addition did not affect growth performance. Rumen fermentation was characterized by low pH and high total volatile fatty acids and reducing sugar concentrations. Calves fed ad libitum showed lower ruminal lactate concentrations than calves fed restrictedly. Ammonia concentrations were highest in calves fed C-100 and lowest in calves fed ad libitum. The recovery of CoEDTA (added to milk replacer) varied between 20.5 and 34.9%, indicating that significant amounts of milk entered the Rumen. Roughage addition decreased the incidence of plaque formation (Rumen mucosa containing focal or multifocal patches with coalescing and adhering papillae covered by a sticky mass of feed, hair and cell debris) and the incidence of calves with poorly developed Rumen mucosa. However, morphometric parameters of the Rumen wall were hardly influenced by the type and level of roughage. Ruminal polysaccharide-degrading enzyme activities reflected the adaptation of the microorganisms to the dietary concentrate and roughage source. Results indicated that in veal calves, the addition of roughage to concentrate diets did not affect growth performance and positively influenced the macroscopic appearance of the Rumen wall.
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effects of supplementing concentrates differing in carbohydrate composition in veal calf diets ii Rumen Development
Journal of Dairy Science, 2006Co-Authors: B.j. Suárez, N Stockhofe, C G Van Reenen, W J J Gerrits, A M Van Vuuren, J DijkstraAbstract:Abstract The objective of this experiment was to examine the effects of concentrates in feed, differing in carbohydrate source, on the Rumen Development of veal calves. For this purpose, 160 male Holstein Friesian×Dutch Friesian crossbred calves were used in a complete randomized block design with a 5×2 factorial arrangement. Dietary treatments consisted of 1) a milk replacer control, 2) a pectin-based concentrate, 3) a neutral detergent fiber-based concentrate, 4) a starch-based concentrate, and 5) a mixed concentrate (equal amounts of the concentrates in treatments 2, 3, and 4). Concentrate diets were provided as pellets in addition to a commercial milk replacer. Calves were euthanized at either 8 or 12 wk of age. Plasma acetate and β -hydroxybutyrate (BHBA) were measured as indicators of Rumen Development. Empty Rumen weight was determined, and wall samples were taken at slaughter. In most calves, a poorly developed Rumen mucosa was observed. Coalescing Rumen papillae with embedded hair, feed particles, and cell debris were found in all calves fed the concentrate diets. Calves fed concentrates had significantly heavier Rumens than calves fed the control diet. In the dorsal location of the Rumen, calves fed concentrate diets showed an increased ratio of mucosa to serosa length compared with calves fed the control diet, whereas in the ventral location only, calves fed the pectin and mixed diets showed larger ratios of mucosa to serosa length. Mucosa thickness and muscle thickness were greater in the ventral and dorsal locations of the Rumen, respectively. In both locations, the NDF diet resulted numerically in the lowest mucosa thickness and highest muscle thickness among the concentrate treatments. At 8 wk, calves fed the concentrate diets had higher plasma acetate concentrations than calves on the control treatment. However, at 12 wk, only NDF-fed calves showed significantly higher plasma acetate concentrations. The plasma BHBA concentrations of calves at 8 wk of age fed the pectin and mixed diets were higher than those of the control diet-fed calves. At 12 wk, no differences in BHBA concentrations were observed among treatments. Results of a principal component analysis indicated that, in addition to Rumen volatile fatty acid concentrations, other factors were likely to affect Rumen Development, and that the relationships between Rumen Development and individual types of volatile fatty acids present in the Rumen liquor were similar. Also, variations in Rumen Development coincided with variations in plasma acetate and BHBA concentrations.
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effects of supplementing concentrates differing in carbohydrate composition in veal calf diets ii Rumen Development
Journal of Dairy Science, 2006Co-Authors: B.j. Suárez, N Stockhofe, C G Van Reenen, W J J Gerrits, A M Van Vuuren, J DijkstraAbstract:The objective of this experiment was to examine the effects of concentrates in feed, differing in carbohydrate source, on the Rumen Development of veal calves. For this purpose, 160 male Holstein Friesian x Dutch Friesian crossbred calves were used in a complete randomized block design with a 5 x 2 factorial arrangement. Dietary treatments consisted of 1) a milk replacer control, 2) a pectin-based concentrate, 3) a neutral detergent fiber-based concentrate, 4) a starch-based concentrate, and 5) a mixed concentrate (equal amounts of the concentrates in treatments 2, 3, and 4). Concentrate diets were provided as pellets in addition to a commercial milk replacer. Calves were euthanized at either 8 or 12 wk of age. Plasma acetate and beta-hydroxybutyrate (BHBA) were measured as indicators of Rumen Development. Empty Rumen weight was determined, and wall samples were taken at slaughter. In most calves, a poorly developed Rumen mucosa was observed. Coalescing Rumen papillae with embedded hair, feed particles, and cell debris were found in all calves fed the concentrate diets. Calves fed concentrates had significantly heavier Rumens than calves fed the control diet. In the dorsal location of the Rumen, calves fed concentrate diets showed an increased ratio of mucosa to serosa length compared with calves fed the control diet, whereas in the ventral location only, calves fed the pectin and mixed diets showed larger ratios of mucosa to serosa length. Mucosa thickness and muscle thickness were greater in the ventral and dorsal locations of the Rumen, respectively. In both locations, the NDF diet resulted numerically in the lowest mucosa thickness and highest muscle thickness among the concentrate treatments. At 8 wk, calves fed the concentrate diets had higher plasma acetate concentrations than calves on the control treatment. However, at 12 wk, only NDF-fed calves showed significantly higher plasma acetate concentrations. The plasma BHBA concentrations of calves at 8 wk of age fed the pectin and mixed diets were higher than those of the control diet-fed calves. At 12 wk, no differences in BHBA concentrations were observed among treatments. Results of a principal component analysis indicated that, in addition to Rumen volatile fatty acid concentrations, other factors were likely to affect Rumen Development, and that the relationships between Rumen Development and individual types of volatile fatty acids present in the Rumen liquor were similar. Also, variations in Rumen Development coincided with variations in plasma acetate and BHBA concentrations.
