Paul Kononoff - Profile on Academia.edu (original) (raw)
Papers by Paul Kononoff
The Professional Animal Scientist, 2006
Eighty Holstein heifers averaging 189.6 ± 6.8 kg of BW were used to evaluate the effects of forag... more Eighty Holstein heifers averaging 189.6 ± 6.8 kg of BW were used to evaluate the effects of forage level and rumen degradable nitrogen source on feed efficiency and structural growth. A randomized complete block design was used with heifers blocked according to BW (≤136.0 kg and >136.0 kg) and assigned to 1 of 4 treatment diets in a 2 × 2 factorial design. Treatments were constructed with 2 levels of forage (65 or 75%) and 2 nitrogen sources. Forage sources were a mixture of corn silage and chopped timothy hay. Nitrogen sources were either soybean meal (SBM) or a slow-release, polymer-coated urea product (Optigen 1200, CPG Nutrients, Syracuse, NY), which was fed at 1.8% of diet DM on low-forage diets and at 1.3% of diet DM on high-forage diets. Average daily gain and feed efficiency did not differ between rations of different forage level or nitrogen source, averaging 0.87 ± 0.05 kg and 7.4 ± 0.5, respectively, across treatments.
Journal of Animal Science, 2015
Journal of Dairy Science, Oct 31, 2006
Statistical power is defined as the probability of correctly rejecting the null hypothesis. Power... more Statistical power is defined as the probability of correctly rejecting the null hypothesis. Power calculations may be useful in planning experiments. The objective of this technical note is to outline an applied method that estimates statistical power of a dairy nutrition experiment that employs a Latin square as the experimental design. Because the SAS MIXED procedure (PROC MIXED) is commonly used to analyze data sets, this note outlines basic programming procedures that may be used to estimate statistical power of a mixed model using this procedure.
Performance and carcass characteristics when sorting feedlot cattle on the basis of phenotype, and leptin genotype along with differential use of β-adrenergic agonists
Canadian Journal of Animal Science, 2015
Kononoff, Paul J.; Gehman, A. M.; Kelzer, J. M.; Karges, K.; and Gibson, M. L., "The effect of fe... more Kononoff, Paul J.; Gehman, A. M.; Kelzer, J. M.; Karges, K.; and Gibson, M. L., "The effect of feeding high-protein distillers dried grains on milk production of Holstein cows" (2009).
Feeding Dried Distillers Grains to Dairy Cattle
Page 1. Feeding Dried Distillers Grains to Dairy Cattle PJ Kononoff 1 , and DA Christensen 2 1 Un... more Page 1. Feeding Dried Distillers Grains to Dairy Cattle PJ Kononoff 1 , and DA Christensen 2 1 University of Nebraska-Lincoln, Lincoln, NE, 68512 2 Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, SK S7N 5A8 ...
The effect of a leptin single nucleotide polymorphism on quality grade, yield grade, and carcass weight of beef cattle
Journal of Animal Science
Feedlot producers could optimize the value of cattle in a given market grid if they were able to ... more Feedlot producers could optimize the value of cattle in a given market grid if they were able to improve the uniformity of the body composition between cattle among loads. Allelic variation due to a single nucleotide transition (cytosine [C] to thymine [T] transition that results in a Arg25Cys) has been demonstrated to be associated with higher leptin mRNA levels in adipose tissue and increased fat deposition in mature beef, but the effect on economically important carcass traits has not been investigated in either market-ready steers or heifers. Therefore, the objective of this study was to determine the effects of a leptin SNP on the quality grade (QG), yield grade (YG), and weight of beef carcasses. A slaughter trial was conducted using 1,435 crossbred finished heifers and 142 crossbred finished steers as they entered the slaughter facility. Canada QG tended (main effect of genotype P = 0.16, but P < 0.01 for both CC vs. TT and CT vs. TT) to be affected by leptin genotype. Specifically, 7.6 and 7.1% more TT carcasses graded Canada AAA or higher than the CT and CC carcasses, respectively, which supports the suggestion that the leptin SNP is associated with carcass fat. The proportion of carcasses grading Canada YG 1, 2, or 3 was affected (P < 0.01, P = 0.05, and P = 0.02 for YG 1, 2, and 3) by leptin genotype. The proportion of TT carcasses of Canada YG 1 was 12.5 and 15.1% lower than that of CT and CC carcasses, respectively, indicating that rearing animals under the same management and feeding system may result in greater carcass fat and a lower probability of the proportion of carcasses grading YG 1 within certain genotypes. The carcass weights of animals with the CC genotype tended (P = 0.07) to be higher than those of the TT genotype (365.5 vs. 362.3 kg). No significant difference was observed between the TT and CT genotypes in carcass weight. The observed associations between leptin genotype and carcass characteristics may represent an opportunity to genetically identify animals that are most likely to reach specific marketing groups.
The Professional Animal Scientist
Five trials (19 treatments) conducted at the University of Nebraska-Lincoln (UNL) on lactating da... more Five trials (19 treatments) conducted at the University of Nebraska-Lincoln (UNL) on lactating dairy cattle were analyzed to determine how the concentration of ADIN in the ration affects total tract N digestibility. Additionally, 6 published studies (13 treatments) were included to expand the data set. Results from the UNL trials showed that as the concentration of ADIN in the ration increased, the digestibility of ADIN also increased. However, the relationship was poor (r 2 = 0.29). To account for random effects among trials, a meta-analysis was conducted. In the UNL trials, as the ration concentration of ADIN increased, total tract N digestibility decreased; this relationship was moderate (r 2 = 0.55). A meta-analysis of the published studies illustrated similar results with a moderate correlation (r 2 = 0.44). All data were combined for a meta-analysis, and similar results illustrated a moderate relationship (r 2 = 0.58). There was positive relationship between ADF and the concentration of ADIN in the UNL trials; however, the relationship was poor (r 2 = 0.19). Additionally, a poor, negative relationship (r 2 = 0.14) was observed between ADF and N digestibility in the UNL trials. Milk yield (31.9 ± 3.1 kg/d) in the UNL trials was unaffected (r 2 = 0.01) by the concentration of ADIN in the ration. These data suggest ADIN is partially digestible, N digestibility is moderately influenced by ADIN concentration in rations, there is a poor relationship between ADF and the concentration of ADIN, and milk yield is unaffected by the concentration of ADIN.
Using Manure Evaluation to Enhance Dairy Cattle Nutrition
Feeding Corn Milling Co-Products to Dairy and Beef Cattle
ABSTRACT
Ruminal bacterial community structure of dairy cows fed conventional and reduced-fat dried distillers grains with solubles
ABSTRACT
Applied principles of feeding fat to lactating dairy cows, with emphasis on byproducts as the primary source
Measuring forage quality of corn silage and understanding the impacts on rumen fermentation in lactating dairy cattle
Abstract Text: Last year the USDA estimated that 113 million tons of corn silage was produced. Th... more Abstract Text: Last year the USDA estimated that 113 million tons of corn silage was produced. This was up 4 percent from the previous year and was also the highest production in the United States since 1982. Given that corn silage is commonly included in diets for dairy cattle at 30-50% of the DM, this crop represents an important feedstuff to the dairy industry. Additionally given that the chemical composition and nutrient availability of this feed may vary, quality of this feedstuff is central to dairy production and profitability. The term forage quality is often defined by the extent to which the forage elicits a productive response. Fundamentally speaking the nature of this response is dependent upon the availability of forage nutrients to rumen microorganism. Plant factors which affect this availability include maturity, hybrid, and growing conditions. Additionally, harvesting and ensiling practices may also affect nutrient availability and these include the method of choppin...
Comparison of efficiency of energy use in Holstein and Jersey dairy cows offered diets containing reduce fat distillers grains RFDDGS
Abstract Text: Fifty six energy balances were completed with 8 Holstein (H) and 8 Jersey (J) mult... more Abstract Text: Fifty six energy balances were completed with 8 Holstein (H) and 8 Jersey (J) multiparous lactating cows to examine the effect of breed on the efficiency of milk production and energy use. Two dietary treatments were fed in a repeated switch back design to compare breeds. Dietary treatments consisted of 24.5% corn silage, 18.4% alfalfa hay, 6.9% grass hay, with either 22.9% rolled corn and 14.8% soybean meal or 4.51% rolled corn, 0% SBM, and 14.5% RFDDGS (dry matter basis). Diets were offered ad libitum for a 28 d adaptation period and 95% ad libitum for a 4 d collection period. During the collection days, ration digestibility and energy use was measured, indirect calorimeter respiration head boxes were used to determine heat production. Across the two treatments, Holstein cows had a significantly higher intake of gross energy (GE) (30 ± 3.96 Mcal/d; P=< 0.01), and higher energy output in feces, urine, methane, heat production (HP), and milk energy (6.5 ± 1.24, 0.1...
Effects of forage particle size and corn oil supplementation related to milk fat depression in dairy cows consuming reduced-fat corn dried distillers grains with solubles
Abstract Text: Four ruminally cannulated Holstein cows averaging (± SD) 116 ± 18 DIM and 686 ± 52... more Abstract Text: Four ruminally cannulated Holstein cows averaging (± SD) 116 ± 18 DIM and 686 ± 52 kg of BW were used in a 4 × 4 Latin square with a 2 × 2 factorial arrangement of treatments to test the effects of forage particle size and dietary concentration of corn oil on milk fat depression (MFD). Cows were housed in individual stalls, milked twice daily and fed once daily to allow ad libitum access to feed. In each 28 d period each cow was offered 1 of 4 TMR that differed in forage particle size by inclusion of grass hay (LONG) or grass hay pellets (SHORT) and 0 or 2 % corn oil (OIL). Chewing activity was monitored visually every 5 minutes for 24 h on d 25. Total rumen evacuation was performed on d 27 and 28 of each period to determine rumen kinetics. Dietary treatments were: 0 % oil + short particle size (OIL0+SHORT); 0 % oil + long particle size (OIL0+LONG); 2 % oil + short particle size (OIL2+SHORT); and 2 % oil + long particle size (OIL2+LONG). Dry matter intake and milk yie...
Rumen-undegradable protein of blood meal, canola meal, low-fat distillers dried grain with solubles, soybean meal, and expeller soybean meal determined using in situ and in vitro ammonia release procedures
Abstract Text: Two Holstein cows (days in milk 70 ± 17 and milk yield 27.3 ± 8.00 kg) fitted with... more Abstract Text: Two Holstein cows (days in milk 70 ± 17 and milk yield 27.3 ± 8.00 kg) fitted with ruminal cannulas were used to determine rumen-undegradable protein (RUP) using an in situ incubation of 16. In addition, the in vitro ammonia (NH3) release procedure was used to estimate RUP. The in vitro NH3 release procedure involves the incubation of equal amounts of N from each feedstuff in ruminal fluid and the measurement of the NH3 and total VFAs produced. Concentrations of NH3and total VFA were adjusted for a blank (only inoculum). The feedstuffs evaluated were: 3 sources of blood meal (BM1, BM2, and BM3), canola meal (CM), low-fat distillers dried grains with solubles (LFDG), soybean meal (SBM), and expeller soybean meal (ESBM). Data from the in situ procedure were analyzed as a randomized complete block design and the model included the fixed effect of feedstuff and the random effects of replicate and load within feedstuff and data from the in vitro ammonia release were analyz...
Abstract Text: Two Holstein cows fitted with ruminal and proximal duodenal cannulas were used to ... more Abstract Text: Two Holstein cows fitted with ruminal and proximal duodenal cannulas were used to determine crude protein (CP) and AA ruminal degradation using an in situ incubation of 16 h and intestinal digestibility using the mobile bag technique (pore size 50 µm). Bacterial contamination of the rumen-undegradable protein (RUP) was corrected using purines or DNA as bacterial markers. The feedstuffs evaluated were: 3 sources of blood meal (BM1, BM2, and BM3), canola meal (CM), low-fat distillers dried grains with solubles (LFDG), soybean meal (SBM), and expeller soybean meal (ESBM). Data were analyzed as a randomized complete block. Ruminal degradation of CP varied (P < 0.001) across feedstuffs, 85.3, 29.8, 40.7, 75.7, 76.9, 68.8, and 37.0 ± 3.93% for BM1, BM2, BM3, CM, LFDG, SBM, and ESBM, respectively. Ruminal degradation of both total essential AA and nonessential AA followed a similar pattern to that of CP. Based on the ratios of AA concentration in the RUP to AA concentrati...
Optimizing the use of fibrous residues in beef and dairy diets
Abstract Text: Increased corn prices over the past decade have altered land use away from traditi... more Abstract Text: Increased corn prices over the past decade have altered land use away from traditional forage in favor of corn. Accordingly, beef and dairy producers have had to adopt non-traditional forage resources into their production systems, many of which have become available as a result of increased corn production. Byproducts of the wet and dry milling industries have been used to replace both corn and forage in beef and dairy diets. Byproducts containing corn bran have large amounts of readily digestible hemicellulose. The use of byproducts may increase milk production, ADG, and G:F in dairy, beef growing, and beef finishing diets, respectively. In beef finishing diets, byproducts allow for use of low quality forages or partial replacement of traditional forages with minimal losses in ADG or G:F by formulating for equal NDF concentrations. Corn residues have become more available due to increases in corn acres and yield. The individual plant components (i.e., husk, leaf, st...
Energy content of reduced-fat dried distillers grains with solubles for lactating dairy cows
Journal of dairy science, Jan 29, 2015
Eight Holstein and 8 Jersey multiparous, lactating cows were used to complete 56 energy balances ... more Eight Holstein and 8 Jersey multiparous, lactating cows were used to complete 56 energy balances to determine the energy content of reduced-fat dried distillers grains with solubles (RFDDGS). A repeated switchback design was used to compare treatments with and without RFDDGS. Diets consisted of 24.2% corn silage, 18.4% alfalfa hay, 6.94% brome hay with either 22.9% rolled corn or 14.8% soybean meal (control), or 8.95% rolled corn, 28.8% RFDDGS, and 0% soybean meal [Co-P; dry-matter (DM) basis]. The inclusion of RFDDGS did not affect DM intake, averaging 21.4 ± 0.53 kg of DM for all cows, but milk production tended to increase from 29.8 to 30.9 ± 1.46 kg/d for control and Co-P treatments, respectively. Milk fat percentage and energy-corrected milk did not differ between treatments, averaging 4.33 ± 0.14% and 34.1 kg/d, respectively. Milk protein was significantly decreased by the Co-P treatment (3.56 and 3.41 ± 0.08% for control and Co-P treatments), but protein yield was not affecte...
The Professional Animal Scientist, 2006
Eighty Holstein heifers averaging 189.6 ± 6.8 kg of BW were used to evaluate the effects of forag... more Eighty Holstein heifers averaging 189.6 ± 6.8 kg of BW were used to evaluate the effects of forage level and rumen degradable nitrogen source on feed efficiency and structural growth. A randomized complete block design was used with heifers blocked according to BW (≤136.0 kg and >136.0 kg) and assigned to 1 of 4 treatment diets in a 2 × 2 factorial design. Treatments were constructed with 2 levels of forage (65 or 75%) and 2 nitrogen sources. Forage sources were a mixture of corn silage and chopped timothy hay. Nitrogen sources were either soybean meal (SBM) or a slow-release, polymer-coated urea product (Optigen 1200, CPG Nutrients, Syracuse, NY), which was fed at 1.8% of diet DM on low-forage diets and at 1.3% of diet DM on high-forage diets. Average daily gain and feed efficiency did not differ between rations of different forage level or nitrogen source, averaging 0.87 ± 0.05 kg and 7.4 ± 0.5, respectively, across treatments.
Journal of Animal Science, 2015
Journal of Dairy Science, Oct 31, 2006
Statistical power is defined as the probability of correctly rejecting the null hypothesis. Power... more Statistical power is defined as the probability of correctly rejecting the null hypothesis. Power calculations may be useful in planning experiments. The objective of this technical note is to outline an applied method that estimates statistical power of a dairy nutrition experiment that employs a Latin square as the experimental design. Because the SAS MIXED procedure (PROC MIXED) is commonly used to analyze data sets, this note outlines basic programming procedures that may be used to estimate statistical power of a mixed model using this procedure.
Performance and carcass characteristics when sorting feedlot cattle on the basis of phenotype, and leptin genotype along with differential use of β-adrenergic agonists
Canadian Journal of Animal Science, 2015
Kononoff, Paul J.; Gehman, A. M.; Kelzer, J. M.; Karges, K.; and Gibson, M. L., "The effect of fe... more Kononoff, Paul J.; Gehman, A. M.; Kelzer, J. M.; Karges, K.; and Gibson, M. L., "The effect of feeding high-protein distillers dried grains on milk production of Holstein cows" (2009).
Feeding Dried Distillers Grains to Dairy Cattle
Page 1. Feeding Dried Distillers Grains to Dairy Cattle PJ Kononoff 1 , and DA Christensen 2 1 Un... more Page 1. Feeding Dried Distillers Grains to Dairy Cattle PJ Kononoff 1 , and DA Christensen 2 1 University of Nebraska-Lincoln, Lincoln, NE, 68512 2 Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, SK S7N 5A8 ...
The effect of a leptin single nucleotide polymorphism on quality grade, yield grade, and carcass weight of beef cattle
Journal of Animal Science
Feedlot producers could optimize the value of cattle in a given market grid if they were able to ... more Feedlot producers could optimize the value of cattle in a given market grid if they were able to improve the uniformity of the body composition between cattle among loads. Allelic variation due to a single nucleotide transition (cytosine [C] to thymine [T] transition that results in a Arg25Cys) has been demonstrated to be associated with higher leptin mRNA levels in adipose tissue and increased fat deposition in mature beef, but the effect on economically important carcass traits has not been investigated in either market-ready steers or heifers. Therefore, the objective of this study was to determine the effects of a leptin SNP on the quality grade (QG), yield grade (YG), and weight of beef carcasses. A slaughter trial was conducted using 1,435 crossbred finished heifers and 142 crossbred finished steers as they entered the slaughter facility. Canada QG tended (main effect of genotype P = 0.16, but P < 0.01 for both CC vs. TT and CT vs. TT) to be affected by leptin genotype. Specifically, 7.6 and 7.1% more TT carcasses graded Canada AAA or higher than the CT and CC carcasses, respectively, which supports the suggestion that the leptin SNP is associated with carcass fat. The proportion of carcasses grading Canada YG 1, 2, or 3 was affected (P < 0.01, P = 0.05, and P = 0.02 for YG 1, 2, and 3) by leptin genotype. The proportion of TT carcasses of Canada YG 1 was 12.5 and 15.1% lower than that of CT and CC carcasses, respectively, indicating that rearing animals under the same management and feeding system may result in greater carcass fat and a lower probability of the proportion of carcasses grading YG 1 within certain genotypes. The carcass weights of animals with the CC genotype tended (P = 0.07) to be higher than those of the TT genotype (365.5 vs. 362.3 kg). No significant difference was observed between the TT and CT genotypes in carcass weight. The observed associations between leptin genotype and carcass characteristics may represent an opportunity to genetically identify animals that are most likely to reach specific marketing groups.
The Professional Animal Scientist
Five trials (19 treatments) conducted at the University of Nebraska-Lincoln (UNL) on lactating da... more Five trials (19 treatments) conducted at the University of Nebraska-Lincoln (UNL) on lactating dairy cattle were analyzed to determine how the concentration of ADIN in the ration affects total tract N digestibility. Additionally, 6 published studies (13 treatments) were included to expand the data set. Results from the UNL trials showed that as the concentration of ADIN in the ration increased, the digestibility of ADIN also increased. However, the relationship was poor (r 2 = 0.29). To account for random effects among trials, a meta-analysis was conducted. In the UNL trials, as the ration concentration of ADIN increased, total tract N digestibility decreased; this relationship was moderate (r 2 = 0.55). A meta-analysis of the published studies illustrated similar results with a moderate correlation (r 2 = 0.44). All data were combined for a meta-analysis, and similar results illustrated a moderate relationship (r 2 = 0.58). There was positive relationship between ADF and the concentration of ADIN in the UNL trials; however, the relationship was poor (r 2 = 0.19). Additionally, a poor, negative relationship (r 2 = 0.14) was observed between ADF and N digestibility in the UNL trials. Milk yield (31.9 ± 3.1 kg/d) in the UNL trials was unaffected (r 2 = 0.01) by the concentration of ADIN in the ration. These data suggest ADIN is partially digestible, N digestibility is moderately influenced by ADIN concentration in rations, there is a poor relationship between ADF and the concentration of ADIN, and milk yield is unaffected by the concentration of ADIN.
Using Manure Evaluation to Enhance Dairy Cattle Nutrition
Feeding Corn Milling Co-Products to Dairy and Beef Cattle
ABSTRACT
Ruminal bacterial community structure of dairy cows fed conventional and reduced-fat dried distillers grains with solubles
ABSTRACT
Applied principles of feeding fat to lactating dairy cows, with emphasis on byproducts as the primary source
Measuring forage quality of corn silage and understanding the impacts on rumen fermentation in lactating dairy cattle
Abstract Text: Last year the USDA estimated that 113 million tons of corn silage was produced. Th... more Abstract Text: Last year the USDA estimated that 113 million tons of corn silage was produced. This was up 4 percent from the previous year and was also the highest production in the United States since 1982. Given that corn silage is commonly included in diets for dairy cattle at 30-50% of the DM, this crop represents an important feedstuff to the dairy industry. Additionally given that the chemical composition and nutrient availability of this feed may vary, quality of this feedstuff is central to dairy production and profitability. The term forage quality is often defined by the extent to which the forage elicits a productive response. Fundamentally speaking the nature of this response is dependent upon the availability of forage nutrients to rumen microorganism. Plant factors which affect this availability include maturity, hybrid, and growing conditions. Additionally, harvesting and ensiling practices may also affect nutrient availability and these include the method of choppin...
Comparison of efficiency of energy use in Holstein and Jersey dairy cows offered diets containing reduce fat distillers grains RFDDGS
Abstract Text: Fifty six energy balances were completed with 8 Holstein (H) and 8 Jersey (J) mult... more Abstract Text: Fifty six energy balances were completed with 8 Holstein (H) and 8 Jersey (J) multiparous lactating cows to examine the effect of breed on the efficiency of milk production and energy use. Two dietary treatments were fed in a repeated switch back design to compare breeds. Dietary treatments consisted of 24.5% corn silage, 18.4% alfalfa hay, 6.9% grass hay, with either 22.9% rolled corn and 14.8% soybean meal or 4.51% rolled corn, 0% SBM, and 14.5% RFDDGS (dry matter basis). Diets were offered ad libitum for a 28 d adaptation period and 95% ad libitum for a 4 d collection period. During the collection days, ration digestibility and energy use was measured, indirect calorimeter respiration head boxes were used to determine heat production. Across the two treatments, Holstein cows had a significantly higher intake of gross energy (GE) (30 ± 3.96 Mcal/d; P=< 0.01), and higher energy output in feces, urine, methane, heat production (HP), and milk energy (6.5 ± 1.24, 0.1...
Effects of forage particle size and corn oil supplementation related to milk fat depression in dairy cows consuming reduced-fat corn dried distillers grains with solubles
Abstract Text: Four ruminally cannulated Holstein cows averaging (± SD) 116 ± 18 DIM and 686 ± 52... more Abstract Text: Four ruminally cannulated Holstein cows averaging (± SD) 116 ± 18 DIM and 686 ± 52 kg of BW were used in a 4 × 4 Latin square with a 2 × 2 factorial arrangement of treatments to test the effects of forage particle size and dietary concentration of corn oil on milk fat depression (MFD). Cows were housed in individual stalls, milked twice daily and fed once daily to allow ad libitum access to feed. In each 28 d period each cow was offered 1 of 4 TMR that differed in forage particle size by inclusion of grass hay (LONG) or grass hay pellets (SHORT) and 0 or 2 % corn oil (OIL). Chewing activity was monitored visually every 5 minutes for 24 h on d 25. Total rumen evacuation was performed on d 27 and 28 of each period to determine rumen kinetics. Dietary treatments were: 0 % oil + short particle size (OIL0+SHORT); 0 % oil + long particle size (OIL0+LONG); 2 % oil + short particle size (OIL2+SHORT); and 2 % oil + long particle size (OIL2+LONG). Dry matter intake and milk yie...
Rumen-undegradable protein of blood meal, canola meal, low-fat distillers dried grain with solubles, soybean meal, and expeller soybean meal determined using in situ and in vitro ammonia release procedures
Abstract Text: Two Holstein cows (days in milk 70 ± 17 and milk yield 27.3 ± 8.00 kg) fitted with... more Abstract Text: Two Holstein cows (days in milk 70 ± 17 and milk yield 27.3 ± 8.00 kg) fitted with ruminal cannulas were used to determine rumen-undegradable protein (RUP) using an in situ incubation of 16. In addition, the in vitro ammonia (NH3) release procedure was used to estimate RUP. The in vitro NH3 release procedure involves the incubation of equal amounts of N from each feedstuff in ruminal fluid and the measurement of the NH3 and total VFAs produced. Concentrations of NH3and total VFA were adjusted for a blank (only inoculum). The feedstuffs evaluated were: 3 sources of blood meal (BM1, BM2, and BM3), canola meal (CM), low-fat distillers dried grains with solubles (LFDG), soybean meal (SBM), and expeller soybean meal (ESBM). Data from the in situ procedure were analyzed as a randomized complete block design and the model included the fixed effect of feedstuff and the random effects of replicate and load within feedstuff and data from the in vitro ammonia release were analyz...
Abstract Text: Two Holstein cows fitted with ruminal and proximal duodenal cannulas were used to ... more Abstract Text: Two Holstein cows fitted with ruminal and proximal duodenal cannulas were used to determine crude protein (CP) and AA ruminal degradation using an in situ incubation of 16 h and intestinal digestibility using the mobile bag technique (pore size 50 µm). Bacterial contamination of the rumen-undegradable protein (RUP) was corrected using purines or DNA as bacterial markers. The feedstuffs evaluated were: 3 sources of blood meal (BM1, BM2, and BM3), canola meal (CM), low-fat distillers dried grains with solubles (LFDG), soybean meal (SBM), and expeller soybean meal (ESBM). Data were analyzed as a randomized complete block. Ruminal degradation of CP varied (P < 0.001) across feedstuffs, 85.3, 29.8, 40.7, 75.7, 76.9, 68.8, and 37.0 ± 3.93% for BM1, BM2, BM3, CM, LFDG, SBM, and ESBM, respectively. Ruminal degradation of both total essential AA and nonessential AA followed a similar pattern to that of CP. Based on the ratios of AA concentration in the RUP to AA concentrati...
Optimizing the use of fibrous residues in beef and dairy diets
Abstract Text: Increased corn prices over the past decade have altered land use away from traditi... more Abstract Text: Increased corn prices over the past decade have altered land use away from traditional forage in favor of corn. Accordingly, beef and dairy producers have had to adopt non-traditional forage resources into their production systems, many of which have become available as a result of increased corn production. Byproducts of the wet and dry milling industries have been used to replace both corn and forage in beef and dairy diets. Byproducts containing corn bran have large amounts of readily digestible hemicellulose. The use of byproducts may increase milk production, ADG, and G:F in dairy, beef growing, and beef finishing diets, respectively. In beef finishing diets, byproducts allow for use of low quality forages or partial replacement of traditional forages with minimal losses in ADG or G:F by formulating for equal NDF concentrations. Corn residues have become more available due to increases in corn acres and yield. The individual plant components (i.e., husk, leaf, st...
Energy content of reduced-fat dried distillers grains with solubles for lactating dairy cows
Journal of dairy science, Jan 29, 2015
Eight Holstein and 8 Jersey multiparous, lactating cows were used to complete 56 energy balances ... more Eight Holstein and 8 Jersey multiparous, lactating cows were used to complete 56 energy balances to determine the energy content of reduced-fat dried distillers grains with solubles (RFDDGS). A repeated switchback design was used to compare treatments with and without RFDDGS. Diets consisted of 24.2% corn silage, 18.4% alfalfa hay, 6.94% brome hay with either 22.9% rolled corn or 14.8% soybean meal (control), or 8.95% rolled corn, 28.8% RFDDGS, and 0% soybean meal [Co-P; dry-matter (DM) basis]. The inclusion of RFDDGS did not affect DM intake, averaging 21.4 ± 0.53 kg of DM for all cows, but milk production tended to increase from 29.8 to 30.9 ± 1.46 kg/d for control and Co-P treatments, respectively. Milk fat percentage and energy-corrected milk did not differ between treatments, averaging 4.33 ± 0.14% and 34.1 kg/d, respectively. Milk protein was significantly decreased by the Co-P treatment (3.56 and 3.41 ± 0.08% for control and Co-P treatments), but protein yield was not affecte...