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Costa C, Baldassini WA, Leal MS, Meirelles PRL, Castilhos AM, Nascimento Júnior NG, Silveira JPF, Pariz CM, Roça RO, Factori MA, Silva MGB. Carcass, meat quality traits, and economic analysis of Nellore bulls fed with finishing feedlot diets containing mechanically processed corn silage. Trop Anim Health Prod 2023; 55:121. [PMID: 36933162 DOI: 10.1007/s11250-023-03525-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 03/06/2023] [Indexed: 03/19/2023]
Abstract
Effects of mechanical processing (MP) of corn silage and its inclusion in feedlot diets on carcass and meat quality traits of Nellore (Bos indicus) were analyzed. Seventy-two bulls aged approximately 18 months and with an initial average body weight of 392.8 ± 22.3 kg were used. The experimental design was a 2 × 2 factorial arrangement, considering the concentrate-roughage (C:R) ratio (40:60 or 20:80), MP of silage and their interactions. After slaughter, hot carcass weight (HCW), pH, temperature, backfat thickness (BFT), and ribeye area (REA), yields of meat cuts (tenderloin, striploin, ribeye steak, neck steak, and sirloin cap), meat quality traits and economic analysis were evaluated. A lower final pH was found in the carcasses of animals consuming diets containing MP versus unprocessed silage (pH = 5.81 versus 5.93). Carcass variables (HCW, BFT, and REA) and meat cut yields were not affected by treatments. The C:R 20:80 increased the intramuscular fat (IMF) content by approximately 1%, without affecting moisture, ash, and protein contents. Meat/fat color (L*, a* and b*) and Warner-Bratzler shear force (WBSF) were similar among treatments. The results indicated that the MP of corn silage in finishing diets can provide better carcass pH results in Nellore bulls, without negatively influencing carcass weight, fatness, and meat tenderness (WBSF). The IMF content of meat was slightly improved using a C:R 20:80 and lower total costs per arroba produced (3.5%), daily costs per animal/day (4.2%), and cost per ton of feeds (5.15%) were found with MP silage.
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Affiliation(s)
- C Costa
- Faculdade de Medicina Veterinária e Zootecnia (FMVZ), Departamento de Melhoramento e Nutrição Animal, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Rua Prof. Dr. Valter Maurício Correa, Botucatu, São Paulo, 18618-681, Brazil.
| | - W A Baldassini
- Faculdade de Medicina Veterinária e Zootecnia (FMVZ), Departamento de Melhoramento e Nutrição Animal, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Rua Prof. Dr. Valter Maurício Correa, Botucatu, São Paulo, 18618-681, Brazil
| | - M S Leal
- Faculdade de Medicina Veterinária e Zootecnia (FMVZ), Departamento de Melhoramento e Nutrição Animal, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Rua Prof. Dr. Valter Maurício Correa, Botucatu, São Paulo, 18618-681, Brazil
| | - P R L Meirelles
- Faculdade de Medicina Veterinária e Zootecnia (FMVZ), Departamento de Melhoramento e Nutrição Animal, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Rua Prof. Dr. Valter Maurício Correa, Botucatu, São Paulo, 18618-681, Brazil
| | - A M Castilhos
- Faculdade de Medicina Veterinária e Zootecnia (FMVZ), Departamento de Melhoramento e Nutrição Animal, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Rua Prof. Dr. Valter Maurício Correa, Botucatu, São Paulo, 18618-681, Brazil
| | - N G Nascimento Júnior
- Faculdade de Medicina Veterinária e Zootecnia (FMVZ), Departamento de Melhoramento e Nutrição Animal, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Rua Prof. Dr. Valter Maurício Correa, Botucatu, São Paulo, 18618-681, Brazil
| | - J P F Silveira
- Faculdade de Medicina Veterinária e Zootecnia (FMVZ), Departamento de Melhoramento e Nutrição Animal, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Rua Prof. Dr. Valter Maurício Correa, Botucatu, São Paulo, 18618-681, Brazil
| | - C M Pariz
- Faculdade de Medicina Veterinária e Zootecnia (FMVZ), Departamento de Melhoramento e Nutrição Animal, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Rua Prof. Dr. Valter Maurício Correa, Botucatu, São Paulo, 18618-681, Brazil
| | - R O Roça
- Faculdade de Medicina Veterinária e Zootecnia (FMVZ), Departamento de Melhoramento e Nutrição Animal, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Rua Prof. Dr. Valter Maurício Correa, Botucatu, São Paulo, 18618-681, Brazil
| | - M A Factori
- Faculdade de Medicina Veterinária e Zootecnia (FMVZ), Departamento de Melhoramento e Nutrição Animal, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Rua Prof. Dr. Valter Maurício Correa, Botucatu, São Paulo, 18618-681, Brazil
| | - M G B Silva
- Faculdade de Medicina Veterinária e Zootecnia (FMVZ), Departamento de Melhoramento e Nutrição Animal, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Rua Prof. Dr. Valter Maurício Correa, Botucatu, São Paulo, 18618-681, Brazil
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Salvati GGS, Santos WP, Silveira JM, Gritti VC, Arthur BAV, Salvo PAR, Fachin L, Ribeiro AP, Morais Júnior NN, Ferraretto LF, Daniel JLP, Beauchemin KA, Santos FAP, Nussio LG. Effect of kernel processing and particle size of whole-plant corn silage with vitreous endosperm on dairy cow performance. J Dairy Sci 2020; 104:1794-1810. [PMID: 33309382 DOI: 10.3168/jds.2020-19428] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 09/21/2020] [Indexed: 11/19/2022]
Abstract
Kernel processing and theoretical length of cut (TLOC) of whole-plant corn silage (WPCS) can affect feed intake, digestibility, and performance of dairy cows. The objective of this study was to evaluate for lactating dairy cows the effects of kernel processing and TLOC of WPCS with vitreous endosperm. The treatments were a pull-type forage harvester without kernel processor set for a 6-mm TLOC (PT6) and a self-propelled forage harvester with kernel processor set for a 6-mm TLOC (SP6), 12-mm TLOC (SP12), and 18-mm TLOC (SP18). Processing scores of the WPCS were 32.1% (PT6), 53.9% (SP6), 49.0% (SP12), and 40.1% (SP18). Twenty-four Holstein cows (139 ± 63 d in milk) were blocked and assigned to six 4 × 4 Latin squares with 24-d periods (18 d of adaptation). Diets were formulated to contain 48.5% WPCS, 15.5% citrus pulp, 15.0% dry ground corn, 9.5% soybean meal, 6.8% low rumen degradability soybean meal, 1.8% calcium soap of palm fatty acids (FA), 1.7% mineral and vitamin mix, and 1% urea (dry matter basis). Nutrient composition of the diets (% of dry matter) was 16.5% crude protein, 28.9% neutral detergent fiber, and 25.4% starch. Three orthogonal contrasts were used to compare treatments: effect of kernel processing (PT6 vs. SP6) and effect of TLOC (particle size; SP6 vs. SP12 and SP12 vs. SP18). Cows fed SP6 produced 1.2 kg/d greater milk yield with no changes in dry matter intake, resulting in greater feed efficiency compared with PT6. Cows fed SP6 also produced more milk protein (+36 g/d), lactose (+61 g/d), and total solids (+94 g/d) than cows fed PT6. The mechanism for increased yield of milk and milk components involved greater kernel fragmentation, starch digestibility, and glucose availability for lactose synthesis by the mammary gland. However, cows fed SP6 had lower chewing time and tended to have greater levels of serum amyloid A compared with PT6. Milk yield was similar for SP6 and SP12, but SP12 cows tended to have less serum amyloid A with greater chewing time. Cows fed SP18 had lower total-tract starch digestibility and tended to have lower plasma glucose and produce less milk compared with cows fed SP12. Compared with PT6, feeding SP6 raised linear odd-chain FA concentration in milk. Similarly, a reduction of these same FA occurred for SP12 compared with SP6. Cows fed SP6 had greater proportion of milk C14:1 and C16:1 compared with PT6 and SP12. Lesser trans C18:1 followed by greater C18:0 concentrations were observed for SP12 and PT6 compared with SP6, which is an indication of more complete biohydrogenation in the rumen. Under the conditions of this study, the use of a self-propelled forage harvester with kernel processing set for a 12-mm TLOC is recommended for WPCS from hybrids with vitreous endosperm.
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Affiliation(s)
- G G S Salvati
- Luiz de Queiroz College of Agriculture - University of São Paulo Piracicaba, SP 13418-900, Brazil.
| | - W P Santos
- Luiz de Queiroz College of Agriculture - University of São Paulo Piracicaba, SP 13418-900, Brazil
| | - J M Silveira
- Luiz de Queiroz College of Agriculture - University of São Paulo Piracicaba, SP 13418-900, Brazil
| | - V C Gritti
- Luiz de Queiroz College of Agriculture - University of São Paulo Piracicaba, SP 13418-900, Brazil
| | - B A V Arthur
- Luiz de Queiroz College of Agriculture - University of São Paulo Piracicaba, SP 13418-900, Brazil
| | - P A R Salvo
- Luiz de Queiroz College of Agriculture - University of São Paulo Piracicaba, SP 13418-900, Brazil
| | - L Fachin
- Luiz de Queiroz College of Agriculture - University of São Paulo Piracicaba, SP 13418-900, Brazil
| | - A P Ribeiro
- Federal Institute of Espírito Santo, Itapina Campus, Colatina, ES 29717-000, Brazil
| | - N N Morais Júnior
- Federal Institute of Espírito Santo, Itapina Campus, Colatina, ES 29717-000, Brazil
| | - L F Ferraretto
- Department of Animal and Dairy Sciences, University of Wisconsin, Madison 53718
| | - J L P Daniel
- Department of Animal Science, State University of Maringá, Maringá, PR 87020900, Brazil
| | - K A Beauchemin
- Agriculture and Agri-Food Canada, Lethbridge, AB, Canada T1J 4B1
| | - F A P Santos
- Luiz de Queiroz College of Agriculture - University of São Paulo Piracicaba, SP 13418-900, Brazil
| | - L G Nussio
- Luiz de Queiroz College of Agriculture - University of São Paulo Piracicaba, SP 13418-900, Brazil
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Ferraretto L, Shaver R, Luck B. Silage review: Recent advances and future technologies for whole-plant and fractionated corn silage harvesting. J Dairy Sci 2018; 101:3937-3951. [DOI: 10.3168/jds.2017-13728] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 09/27/2017] [Indexed: 11/19/2022]
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Affiliation(s)
- Michael S. Allen
- Department of Animal Science; Michigan State University; East Lansing Michigan
| | - James G. Coors
- Department of Agronomy; University of Wisconsin; Madison Wisconsin
| | - Gregory W. Roth
- Department of Crop and Soil Sciences; Pennsylvania State University; University Park Pennsylvania
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Ferraretto L, Crump P, Shaver R. Effect of cereal grain type and corn grain harvesting and processing methods on intake, digestion, and milk production by dairy cows through a meta-analysis. J Dairy Sci 2013; 96:533-50. [DOI: 10.3168/jds.2012-5932] [Citation(s) in RCA: 146] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Accepted: 10/02/2012] [Indexed: 01/13/2023]
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Meta-analysis: Effect of corn silage harvest practices on intake, digestion, and milk production by dairy cows. ACTA ACUST UNITED AC 2012. [DOI: 10.15232/s1080-7446(15)30334-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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TANIGAWA T, OOSAKA I, KAWAMOTO S, HARA S. Effect of roll clearance of mechanical processing of corn silage harvested at the black-line stage of maturity on carbohydrate and protein utilization in dairy cows. Anim Sci J 2011; 83:213-9. [DOI: 10.1111/j.1740-0929.2011.00950.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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HARA S, TANIGAWA T. Effects of length of cut and mechanical processing on utilization of corn silage harvested at the black line stage of maturity by lactating dairy cows. Anim Sci J 2010; 81:187-93. [DOI: 10.1111/j.1740-0929.2009.00719.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ferreira G, Mertens DR. Chemical and Physical Characteristics of Corn Silages and Their Effects on In Vitro Disappearance. J Dairy Sci 2005; 88:4414-25. [PMID: 16291633 DOI: 10.3168/jds.s0022-0302(05)73128-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Estimating the available energy in corn silage provides a unique challenge because the silage contains variable proportions of grain and stover, each of which can differ in availability due to chemical composition and physical form. The objectives of this study were to investigate relationships among chemical components and their relationships with in vitro disappearance of ground and unground dried silages, and to quantify minimally fragmented starch in corn silage and investigate its impact and that of mean particle size (MPS) on in vitro disappearance of unground silages. Thirty-two corn silages were selected to provide diversity in dry matter, protein, fiber, and MPS. Detergent fibers were highly correlated with each other and with nonfiber carbohydrates, and were used to develop prediction equations between these constituents. Sieves with apertures > or =4.75 mm were used to isolate intact kernels and large kernel fragments, which were collected and analyzed to measure minimally fragmented starch (Starch>4.75). Dividing Starch>4.75 by total starch defined the proportion of minimally fragmented starch (Starch>4.75/Total), which ranged from 9 to 100% with a mean of 52%. Starch>4.75/Total was positively correlated with MPS (r = 0.46). The inverse of Starch>4.75/Total is an index of kernel fragmentation. Silages were prepared as whole material or ground to pass through a 4- or 1-mm screen of a cutter mill. In vitro dry matter disappearance (IVDMD) was greater for ground than for whole samples (71.7 and 61.2%, respectively). Increased IVDMD for ground samples was attributed to greater in vitro neutral detergent fiber (NDF) and neutral detergent solubles (NDS) disappearances. The IVDMD of ground samples was related to NDF and acid detergent lignin (R2 = 0.80). The IVDMD of whole corn silage was related to acid detergent lignin, Starch>4.75, MPS, and dry matter. When IVDMD was partitioned into in vitro digestible NDS (IVdNDS) and in vitro digestible NDF, the IVdNDS of whole was not uniform or completely fermented. The difference in IVdNDS between ground and whole was related to Starch>4.75/Total. In conclusion, the proportion of minimally fragmented starch provides a corn silage fragmentation index that is related to the in vitro digestion of whole silages that, if validated by in vivo trials, may be a useful quantitative substitute for the qualitative processing adjustment factor that is used currently in summative equations for estimating the total digestible nutrients of corn silages.
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Affiliation(s)
- G Ferreira
- Dairy Science Department, University of Wisconsin-Madison, Madison, 53706, USA.
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Seymour W, Campbell D, Johnson Z. Relationships between rumen volatile fatty acid concentrations and milk production in dairy cows: a literature study. Anim Feed Sci Technol 2005. [DOI: 10.1016/j.anifeedsci.2004.10.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Cooke KM, Bernard JK. Effect of Length of Cut and Kernel Processing on Use of Corn Silage by Lactating Dairy Cows. J Dairy Sci 2005; 88:310-6. [PMID: 15591394 DOI: 10.3168/jds.s0022-0302(05)72689-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Forty Holstein cows were used in an 8-wk randomized block design trial to determine the effects of theoretical length of cut (TLC) and kernel processing (KP) of whole plant corn silage on nutrient intake and digestibility, milk yield, and milk composition. Corn was harvested at three-quarters milk line stage of maturity at TLC of 1.90 or 2.54 cm. At each TLC, corn was KP at either 2 or 8 mm roll clearance. The control was harvested at 1.90 cm without KP. Corn silage provided 38% of the dietary dry matter (DM) in the experimental diets. Intake of DM and nutrients was similar among treatments. Apparent digestibility of DM and acid detergent fiber (ADF) increased with increasing TLC. Fiber digestibility was improved by KP compared with unprocessed corn silage. Starch digestibility was greater for corn silage KP at 2 vs. 8 mm. Apparent digestibility of DM, crude protein, and ADF was lowest for the diet containing silage harvested at 2.54 cm TLC and KP at 8 mm, resulting in an interaction of TLC and KP. No differences were observed in DM intake (DMI) among treatments. An interaction of TLC and KP was observed, however, for yield of milk protein and energy-corrected milk (ECM) and efficiency of converting DMI to ECM because of lower yield for diets containing silage harvested at 2.54 cm TLC and KP at 8 mm. Results of this trial indicate that as TLC increases, aggressive KP is necessary to maintain nutrient digestibility and performance of lactating dairy cows.
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Affiliation(s)
- K M Cooke
- Department of Animal and Dairy Science, The University of Georgia, Tifton, 31793-0748, USA
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Ebling TL, Kung L. A Comparison of Processed Conventional Corn Silage to Unprocessed and Processed Brown Midrib Corn Silage on Intake, Digestion, and Milk Production by Dairy Cows. J Dairy Sci 2004; 87:2519-26. [PMID: 15328275 DOI: 10.3168/jds.s0022-0302(04)73376-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We studied the effects of mechanical processing and type of hybrid on the nutritive value of corn silage for lactating cows. Treatments were brown midrib (BMR) corn silage that was unprocessed (U-BMR), BMR corn silage that was processed (P-BMR), and a conventional corn silage that was processed (P-7511). All silages were harvested at a theoretical chop length of 19 mm. The chemical compositions of the silages were similar among treatments except that BMR silages were lower in lignin and higher in protein than P-7511. Brown midrib silages had greater 30-h in situ and in vitro NDF digestion than did P-7511, and processing had no effect on 30-h in situ and in vitro fiber digestion, but it increased in situ starch digestion after 3 and 12 h of incubation. Both processed silages had a smaller proportion of particles >1.91 cm and fewer whole corn kernels compared with unprocessed silage. Lactating cows were fed a total mixed ration (TMR) consisting of 42% of each silage type, 40% concentrate, 10% alfalfa silage, and 8% alfalfa hay (DM basis). Cows fed TMR containing P-BMR ate more DM and produced more milk than cows fed P-7511. At feeding, the TMR containing U-BMR had a larger proportion of particles >1.91 cm when compared with the TMR of cows fed processed silages, and after 24 h the difference was even greater, indicating that cows fed unprocessed corn silage sorted more. Cows fed TMR with P-7511 and P-BMR had greater total tract digestibility of organic matter, crude protein, and starch compared with cows fed U-BMR. In vivo digestibility of neutral detergent fiber was greatest for cows fed P-BMR when compared with the other treatments.
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Affiliation(s)
- T L Ebling
- Delaware Agricultural Experimental Station Department of Animal and Food Sciences, College of Agriculture and Natural Resources, University of Delaware, Newark 19716-2150, USA
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Ouellet DR, Lapierre H, Chiquette J. Effects of Corn Silage Processing and Amino Acid Supplementation on the Performance of Lactating Dairy Cows. J Dairy Sci 2003; 86:3675-84. [PMID: 14672198 DOI: 10.3168/jds.s0022-0302(03)73973-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This experiment was conducted to determine the effect of crop processing and amino acid supplementation on dairy cow performance. Corn silage processed (PCS) or unprocessed (UCS) was used as the main forage (45% of dry matter, DM) in a total mixed ration (TMR). Each TMR was either supplemented (AA) or not (AAO) with ruminally protected amino acids (lysine, 3 g/d and methionine, 14 g/d). Thirty-two (551 kg) Holstein cows were randomly assigned to four treatments: PCS-AA, PCS-AA0, UCS-AA, and UCS-AA0 in a 2 x 2 factorial structure. Between wk 7 and 17 of lactation, cows were fed ad libitum TMR comprising 45% of corn silage plus 1 kg of grass hay once a day. The UCS presented better fermentation characteristics than PCS. Dry matter intake (DMI) of the TMR was not affected by treatment and averaged 22.7 kg/d. Energy-corrected milk (ECM) production was 9% higher with UCS than with PCS (33.1 vs. 30.1 kg/d). Milk efficiency was therefore 6% higher with UCS than with PCS (1.43 vs. 1.35 kg ECM/kg of DMI). The concentration of major milk constituents (fat, protein, lactose, urea) was not affected by treatments. Apparent digestibility of DM, organic matter, N, starch, acid detergent fiber, and neutral detergent fiber were similar among treatments. The effective ruminal degradability of DM, starch, and protein, however, was greater with PCS than with UCS. Amino acid supplementation had no effect on milk production nor on milk constituents, whether it was used with processed corn silage or with unprocessed corn silage. These data indicate that feeding UCS resulted in a greater milk production compared with PCS. The numerically higher DMI, a potentially greater intestinal digestion of starch or the better conservation of UCS could have contributed to the greater milk production.
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Affiliation(s)
- D R Ouellet
- Dairy and Swine Research and Development Centre, Agriculture and Agri-Food Canada, Lennoxville, Canada.
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14
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Schwab EC, Shaver RD, Lauer JG, Coors JG. Estimating silage energy value and milk yield to rank corn hybrids. Anim Feed Sci Technol 2003. [DOI: 10.1016/s0377-8401(03)00210-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
The human diet contains numerous endocrine-active compounds that influence mammalian physiology. The effects of these dietary compounds may be mediated by interaction with well-characterized intracellular hormone receptors or by other effects on patterns of endogenous hormone production, metabolism, target tissue signaling, growth, or differentiation. Because humans evolved as omnivores, the spectrum of dietary compounds that can be tolerated at modest levels of intake without frank toxicity is broad. Modest intake of these diverse nonnutritive endocrine-active compounds offers potential human health benefits through modulation of metabolic and hormonal responses, especially in sedentary individuals consuming a highly refined diet.
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Affiliation(s)
- Claude L Hughes
- Department of Medical and Scientific Services, Quintiles, Inc, Research Triangle Park, NC 27709-3979, USA.
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Johnson LM, Harrison JH, Davidson D, Mahanna WC, Shinners K. Corn silage management: effects of hybrid, chop length, and mechanical processing on digestion and energy content. J Dairy Sci 2003; 86:208-31. [PMID: 12613866 DOI: 10.3168/jds.s0022-0302(03)73601-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Two experiments were conducted to evaluate the effects of chop length and mechanical processing of two hybrids of whole plant corn on digestion and energy content of the total mixed ration (TMR). The experimental designs in experiments 1 and 2 were 6 x 6 and 4 x 4 Latin squares, respectively. In the first experiment, Pioneer hybrid 3845 was harvested at three theoretical lengths of cut: 11.1, 27.8, and 39.7 mm. At each chop length, corn was harvested with and without mechanical processing using a John Deere 5830 harvester with an onboard kernel processor. In the second experiment, Pioneer hybrid Quanta was harvested at two theoretical lengths of cut: 27.8 and 39.7 mm, with and without mechanical processing. In both experiments, the increase in the theoretical length of cut of corn silage increased the average length of cut and tended to increase the percentage of particles greater than 19 mm and lower the percentage of particles between 8 and 19 mm. In experiment 1, apparent total tract dry matter, organic matter, and neutral detergent fiber (NDF) digestibilities were lower for cows fed diets containing corn silage harvested at a short chop length (11.1 mm) than for corn silage harvested at a long chop length (39.7 mm). The lower total tract digestibility of nutrients may have contributed to the lower TDN, metabolizable energy (percentage of digestible energy), and NEL concentration of diets containing the short chop length corn silage (experiment 1). In experiment 2, total tract starch digestibility was greater for cows fed medium chop (27.8 mm) corn silage diets, and total tract NDF digestibility was greater for cows fed long chop (39.7 mm) corn silage diets. The opposing effect of total tract starch and fiber digestibilities between chop lengths may have contributed to the lack of difference in energy content of the diets in experiment 2. The TDN and NEL concentrations of the processed corn silage diets were greater than the unprocessed corn silage diets in experiment 1. The increase in energy concentration for the processed corn silage diet was due to greater total tract digestibility of organic matter and ether extract. Total tract starch digestibility was greater, and total tract NDF digestibility was lower for cows fed processed corn silage diets than unprocessed corn silage diets in experiment 2. The opposing effect of total tract starch and fiber digestibilities between processed and unprocessed corn silage may have contributed to the lack of difference in energy content of the diets.
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Affiliation(s)
- L M Johnson
- Department of Animal Sciences, Washington State University, Puyallup, 98371, USA
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Correa CES, Shaver RD, Pereira MN, Lauer JG, Kohn K. Relationship between corn vitreousness and ruminal in situ starch degradability. J Dairy Sci 2002; 85:3008-12. [PMID: 12487466 DOI: 10.3168/jds.s0022-0302(02)74386-5] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The objective of this experiment was to determine the relationship between corn kernel vitreousness and ruminal in situ starch degradation. Fourteen U.S. and five Brazilian corn hybrids cultivated in their respective countries were evaluated. The U.S. dent hybrids were harvested at one-half milk line, black layer, and 21 d after black layer stages of maturity. Brazilian flint hybrids were harvested only at the latest stage of maturity. Vitreousness was determined by manual dissection of the kernels. Ruminal in situ degradation of starch was determined in three lactating Holstein cows fitted with ruminal cannulae. Vitreousness of the five mature Brazilian hybrids averaged 73.1% (range of 64.2% to 80.0%), while vitreousness of the 14 mature U.S. hybrids averaged 48.2% (range of 34.9% to 62.3%). Within the 14 U.S. hybrids, average vitreousness increased from 42.8% to 48.2% as stage of maturity progressed from one-half milk line to 21 d after black layer. The correlation between kernel density and vitreousness was 0.87. The correlations between kernel vitreousness or density and ruminal starch availability were -0.93 and -0.87, respectively. With advancing maturity, kernel vitreousness and density increased while ruminal starch availability decreased. Kernel vitreousness and density may be useful parameters for which to select corn hybrids for high ruminal starch availability. Density may be a more practical measurement than vitreousness for screening large corn data sets.
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Affiliation(s)
- C E S Correa
- Universidade Federal de Lavras, Departamento de Zootecnia, Lavras, Brazil, 37200-000
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Johnson LM, Harrison JH, Davidson D, Swift M, Mahanna WC, Shinners K. Corn silage management III: effects of hybrid, maturity, and processing on nitrogen metabolism and ruminal fermentation. J Dairy Sci 2002; 85:2928-47. [PMID: 12487460 DOI: 10.3168/jds.s0022-0302(02)74380-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Two experiments were conducted to evaluate the effects of maturity and mechanical processing of two hybrids of whole plant corn silage on DM and OM digestibility, nitrogen metabolism, ruminal fermentation, and milk production and composition in lactating Holstein cows. In the first experiment, Pioneer hybrid 3845 whole plant corn was harvested at hard dough, one-third milkline, and two-thirds milkline with a theoretical length-of-cut of 6.4 mm. At each stage of maturity, corn was harvested with (1-mm roll clearance) and without (15.9-mm roll clearance) mechanical processing using a John Deere 5830 harvester with an on-board kernel processor. In the second experiment, Pioneer hybrids 3845 and Quanta were harvested at one-third milkline, two-thirds milkline, and blackline stages of maturity with and without mechanical processing. The theoretical length-of-cut was 12.7 mm. Total tract DM and OM digestibilities were lower for cows fed diets containing processed corn silage in experiment 1, and tended to be lower for cows fed diets containing unprocessed corn silage in experiment 2. Ruminal acetate concentrations were greater and ruminal propionate concentrations were lower 2 and 6 h after feeding for cows fed diets containing corn silage harvested at physiological maturity in experiment 2. This was due to decreased digestion of starch at advanced maturities in experiment 2. Ruminal pH tended to decline rapidly after feeding for cows fed hybrid Quanta (2 h) compared to hybrid 3845 (5 h) corn silage based diets. Ruminal acetate concentrations decreased and ruminal propionate concentrations increased 2 and 6 h after feeding for cows fed diets containing hybrid Quanta corn silage compared to hybrid 3845 corn silage. This was related to a greater starch concentration in the corn silage, greater starch intake, and increased rate of starch digestion for cows fed hybrid Quanta corn silage-based diets. Microbial nitrogen flow was lower and feed nitrogen flow was greater for cows fed diets containing hybrid Quanta corn silage. The lower microbial nitrogen flow was due to lower microbial nitrogen concentration and nonammonia nitrogen flow to the duodenum. Milk fat and protein concentrations had a strong quadratic relationship with forage NDF intake as a percentage of body weight. When forage NDF intake as a percentage of body weight dropped below 0.70%, there was a rapid decline in milk fat and protein concentrations.
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Affiliation(s)
- L M Johnson
- Department of Animal Sciences, Washington State University, Puyallup 98371, USA
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Johnson LM, Harrison JH, Davidson D, Swift M, Mahanna WC, Shinners K. Corn silage management II: effects of hybrid, maturity, and mechanical processing on digestion and energy content. J Dairy Sci 2002; 85:2913-27. [PMID: 12487459 DOI: 10.3168/jds.s0022-0302(02)74379-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Two experiments were conducted to evaluate the effects of maturity and mechanical processing of two hybrids of whole plant corn on starch, fiber, and ether extract digestibilities and energy content of the total mixed ration fed to lactating Holstein cows. In the first experiment, Pioneer hybrid 3845 whole plant corn was harvested at hard dough, one-third milkline, and two-thirds milkline with a theoretical length of cut of 6.4 mm. At each stage of maturity, corn was harvested with and without mechanical processing. In the second experiment, Pioneer hybrids 3845 and Quanta were harvested at one-third milkline, two-thirds milkline, and blackline stages of maturity with and without mechanical processing. The theoretical length of cut was 12.7 mm. The measured TDN and NEL concentrations were lower for diets containing processed corn silage in experiment 1 and greater for diets containing processed corn silage in experiment 2, compared with diets containing unprocessed corn silage. The lower energy content for diets containing processed corn silage in experiment 1 can be explained by the lower total tract NDF, ether extract, and CP digestibilities. The greater energy content for diets containing processed corn silage in experiment 2 can be attributed to greater total tract starch and NDF digestibilities for cows fed processed corn silage diets. In experiment 2, diets containing processed corn silage (1.59 Mcal/kg) had approximately 2.6% more energy available per kilogram of DM consumed compared with diets containing unprocessed corn silage (1.55 Mcal/kg). For hybrid Quanta in experiment 2, the TDN and NEL concentrations of diets containing corn silage harvested at two-thirds ML were greater than at other maturities.
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Affiliation(s)
- L M Johnson
- Department of Animal Sciences, Washington State University, Puyallup 98371, USA
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Schwab EC, Shaver RD, Shinners KJ, Lauer JG, Coors JG. Processing and chop length effects in brown-midrib corn silage on intake, digestion, and milk production by dairy cows. J Dairy Sci 2002; 85:613-23. [PMID: 11949866 DOI: 10.3168/jds.s0022-0302(02)74115-5] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In this experiment, we evaluated the influence of increasing chop length and mechanical processing of whole-plant brown-midrib corn silage on intake, digestion, and milk production by dairy cows. Corn silage treatments were harvested at three-quarter milk line stage of maturity at 13- and 19-mm theoretical chop length without processing, or at 19- and 32-mm theoretical chop length with processing at a 2-mm roll clearance. Twenty-four multiparous Holstein cows that averaged 102 +/- 17 d in milk at trial initiation were randomly assigned to treatments in a replicated 4 x 4 Latin square design with 28-d periods. Preplanned orthogonal contrasts were used to evaluate effects of processing (19 processed vs. 19 mm unprocessed) and chop length (13 vs. 19 mm unprocessed and 19 vs. 32 mm processed). Treatments were fed in total mixed rations containing 60% forage (67% corn silage and 33% alfalfa silage) and 40% shelled corn and soybean meal-based concentrate (dry matter basis). Milk yield was unaffected by treatment. Dry matter intake was unaffected by corn silage processing, but increasing corn silage chop length reduced dry matter intake in unprocessed (26.6 vs. 25.5 kg/d) and processed (25.9 vs. 25.1 kg/d) chop length contrasts. Processing reduced milk fat content (3.36 vs. 3.11%) and yield (1.43 vs. 1.35 kg/d), increased total-tract starch digestion (92.9 vs. 97.4%), and decreased total-tract neutral detergent fiber digestion (51.0 vs. 41.8%). Total chewing time (min/d) was unaffected by treatment. Masticate mean particle length was unaffected by chop length in unprocessed and processed corn silage treatments. In this study with brown-midrib corn silage fed to dairy cows producing 43 kg/d of milk, there were no benefits from crop processing or increasing chop length on lactation performance.
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Affiliation(s)
- E C Schwab
- Department of Dairy Science, University of Wisconsin, Madison 53706, USA
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