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Huot F, Claveau S, Bunel A, Warner D, Santschi DE, Gervais R, Paquet ER. Predicting subacute ruminal acidosis from milk mid-infrared estimated fatty acids and machine learning on Canadian commercial dairy herds. J Dairy Sci 2024:S0022-0302(24)00984-6. [PMID: 38971559 DOI: 10.3168/jds.2024-25034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 06/08/2024] [Indexed: 07/08/2024]
Abstract
Our objective was to validate the possibility of detecting SARA from milk Fourier transform mid-infrared spectroscopy estimated fatty acids (FA) and machine learning. Subacute ruminal acidosis is a common condition in modern commercial dairy herds for which the diagnostic remains challenging due to its symptoms often being subtle, nonexclusive, and not immediately apparent. This observational study aimed at evaluating the possibility of predicting SARA by developing machine learning models to be applied to farm data and to provide an estimated portrait of SARA prevalence in commercial dairy herds. A first data set composed of 488 milk samples of 67 cows (initial DIM = 8.5 ± 6.18; mean ± SD) from 7 commercial dairy farms and their corresponding SARA classification (SARA+ if rumen pH <6.0 for 300 min, else SARA-) was used for the development of machine learning models. Three sets of predictive variables: i) milk major components (MMC), ii) milk FA (MFA), and iii) MMC combined with MFA (MMCFA) were submitted to 3 different algorithms, namely Elastic net (EN), Extreme gradient boosting (XGB), and Partial least squares (PLS), and evaluated using 3 different scenarios of cross-validation. Accuracy, sensitivity, and specificity of the resulting 27 models were analyzed using a linear mixed model. Model performance was not significantly affected by the choice of algorithm. Model performance was improved by including fatty acids estimations (MFA and MMCFA as opposed to MMC alone). Based on these results, one model was selected (algorithm: EN; predictive variables: MMCFA; 60.4, 65.4, and 55.3% of accuracy, sensitivity, and specificity, respectively) and applied to a large data set comprising the first test-day record (milk major components and FA within the first 70 DIM of 211,972 Holstein cows (219,503 samples) collected from 3001 commercial dairy herds. Based on this analysis, the within-herd SARA prevalence of commercial farms was estimated at 6.6 ± 5.29% ranging from 0 to 38.3%. A subsequent linear mixed model was built to investigate the herd-level factors associated to higher within-herd SARA prevalence. Milking system, proportion of primiparous cows, herd size and seasons were all herd-level factors affecting SARA prevalence. Furthermore, milk production was positively, and milk fat yield negatively associated with SARA prevalence. Due to their moderate levels of accuracy, the SARA prediction models developed in our study, using data from continuous pH measurements on commercial farms, are not suitable for diagnostic purpose. However, these models can provide valuable information at the herd level.
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Affiliation(s)
- F Huot
- Département des sciences animales, Université Laval, Québec, QC, G1V 0A6, Canada; Institut intelligence et données, Université Laval, Québec, QC, G1V 0A6, Canada; Centre de recherche en données massives, Université Laval, Québec, G1V 0A6, Canada
| | | | - A Bunel
- Agrinova, Alma, QC, G8B 7S8, Canada
| | - D Warner
- Lactanet, Ste-Anne-de-Bellevue, QC, H9X 3R4, Canada
| | - D E Santschi
- Lactanet, Ste-Anne-de-Bellevue, QC, H9X 3R4, Canada
| | - R Gervais
- Département des sciences animales, Université Laval, Québec, QC, G1V 0A6, Canada.
| | - E R Paquet
- Département des sciences animales, Université Laval, Québec, QC, G1V 0A6, Canada; Institut intelligence et données, Université Laval, Québec, QC, G1V 0A6, Canada; Centre de recherche en données massives, Université Laval, Québec, G1V 0A6, Canada.
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2
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Nagahaka N, Abe E, Hiraoka H, Kondo M. Intraday and interday variations of milk fatty acids in dairy cows in early and late lactation. Anim Sci J 2024; 95:e13939. [PMID: 38572588 DOI: 10.1111/asj.13939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 02/09/2024] [Accepted: 02/26/2024] [Indexed: 04/05/2024]
Abstract
The composition of milk fatty acid (FA) was determined using Fourier-transform mid-infrared spectroscopy, which enables the rapid measurement of many samples. Milk FA is one indicator supporting the management of dairy cows and herds. This study aimed to determine an appropriate sampling method for milk FA in a practical farm condition based on intraday and interday variations in milk FA composition during early and late lactation stages. Milk samples were collected in the morning (07:00-08:00 h) and afternoon (16:30-17:30 h) for five consecutive days during early and late lactation. Within the day, de novo FA as the total FA basis was higher in the morning than in the afternoon, whereas preformed FA as the total FA basis was lower in the morning than in the afternoon. The weighted averages of milk FA composition according to milk yield collected in the morning and afternoon were significantly different between cows in early and late lactation; however, these were not significantly different among the consecutive five sampling days in each period. It was concluded that milk samples collected in the morning and afternoon for 1 day are suitable for milk FA determination. These results provide basic data for determining precise sampling methods for practical farms.
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Affiliation(s)
| | - Eisuke Abe
- Graduate School of Bioresources, Mie University, Tsu, Japan
| | | | - Makoto Kondo
- Graduate School of Bioresources, Mie University, Tsu, Japan
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Van Soest BJ, Pereira MN, Duffield TF, Steele MA, DeVries TJ. Effect of pre- and postpartum supplementation of a pure glycerol product to dairy cows on feed intake, metabolic markers, and milk yield and components. J Dairy Sci 2023; 106:6798-6815. [PMID: 37500425 DOI: 10.3168/jds.2022-23173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 03/27/2023] [Indexed: 07/29/2023]
Abstract
The objective of this study was to quantify the effects of supplementing transition dairy cows with a low inclusion dry glycerol product in the pre- and postpartum periods on feed intake, metabolic markers, and milk yield and components. Multiparous Holstein dairy cows (n = 60) were enrolled in a 2-by-2 factorial design study. Starting 21 d before expected parturition, cows individually received a dry cow diet with (1) 250 g/d glycerol product supplementation [66% pure glycerol (United States Pharmacopeia grade); GLY], or (2) no supplementation (CON) mixed to their total mixed ration. After parturition, cows, again, were individually assigned to either GLY, or (2) no supplementation (CON) to their partial mixed ration for the first 21 d in milk (DIM). Cows were milked by an automated milking system and offered a target of 5.4 kg DM/d pellet (23% of target total dry matter intake, DMI) in the automated milking system and followed for 42 d into lactation. Blood samples were collected 6.3 ± 3.47 d before calving for all blood measures and 3, 7, 10, and 14 DIM for analysis of glucose and β-hydroxybutyrate, as well as 3 and 7 DIM for nonesterified fatty acids (NEFA) and haptoglobin. Initial dry cow body weight (BW), calf birth weight, previous 305-d milk, and month of parturition were used as covariates in the statistical model. Cows supplemented with GLY prepartum lost less BW and consumed more DMI pre- and postpartum, as well as had lower postpartum blood β-hydroxybutyrate and NEFA concentrations compared with those fed the CON treatment prepartum. Cows supplemented with GLY postpartum had lesser DMI in the first 42 DIM than cows fed CON postpartum, but also had reduced blood NEFA concentrations, odds of a high haptoglobin test, odds of a low blood glucose test, and lesser preformed fatty acid concentrations and yields in their milk. Cows supplemented glycerol both pre- and postpartum lost the least total BW from -21 to 21 DIM. No treatment effects were detected for milk yield; however, cows receiving GLY postpartum had lower milk fat. Overall, glycerol supplementation during the transition period, particularly during the 21 d before calving, was associated with markers of improved metabolic status.
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Affiliation(s)
- B J Van Soest
- Department of Animal Bioscience, University of Guelph, Guelph, ON, Canada N1G1Y2
| | - M N Pereira
- Department of Animal Science, University of Lavras, Lavras, MG, 37200-900, Brazil
| | - T F Duffield
- Department of Population Medicine, University of Guelph, Guelph, ON, Canada N1G1Y2
| | - M A Steele
- Department of Animal Bioscience, University of Guelph, Guelph, ON, Canada N1G1Y2
| | - T J DeVries
- Department of Animal Bioscience, University of Guelph, Guelph, ON, Canada N1G1Y2.
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Thorsteinsson M, Weisbjerg MR, Lund P, Bruhn A, Hellwing ALF, Nielsen MO. Effects of dietary inclusion of 3 Nordic brown macroalgae on enteric methane emission and productivity of dairy cows. J Dairy Sci 2023; 106:6921-6937. [PMID: 37641361 DOI: 10.3168/jds.2023-23437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 05/19/2023] [Indexed: 08/31/2023]
Abstract
Macroalgae are receiving increased attention as antimethanogenic feed additives for cattle, but most in vivo studies are limited to investigating effects of the red macroalgae Asparagopsis spp. Hence, this study aimed to investigate the CH4 mitigating potential of 3 brown macroalgae from the Northern Hemisphere when fed to dairy cows, and to study the effects on feed intake, milk production, feed digestibility, and animal health indicators. The experiment was conducted as a 4 × 4 Latin square design using 4 lactating rumen, duodenal, and ileal cannulated Danish Holstein dairy cows. The cows were fed a total mixed ration (TMR) without any macroalgae or the same TMR diluted with, on a dry matter basis, either 4% ensiled Saccharina latissima, 4% Ascophyllum nodosum (NOD), or 2% Sargassum muticum (MUT). Each period consisted of 14 d of adaptation, 3 d of digesta and blood sampling, and 4 d of gas exchange measurements using respiration chambers. Milk yield and dry matter intake (DMI) were recorded daily. Blood was sampled on d 13 and 16 and analyzed for health status indicators. None of the 3 species affected the CH4 emission. Moreover, milk yield and DMI were also unaffected. Total-tract digestibility of crude protein was significantly lower for NOD compared with other diets, and additionally, the NOD diet also tended to reduce total-tract digestibility of neutral detergent fiber compared with MUT. Blood biomarkers did not indicate negative effects of the dietary inclusion of macroalgae on cow health. In conclusion, none of the 3 brown macroalgae reduced CH4 emission and did not affect DMI and milk production of dairy cows, whereas negative effects on the digestibility of nutrients were observed when A. nodosum was added. None of the diets would be allowed to be fed in commercial dairy herds due to high contents of iodine, cadmium, and arsenic.
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Affiliation(s)
- M Thorsteinsson
- Department of Animal and Veterinary Sciences, AU-Viborg, Research Centre Foulum, Aarhus University, DK-8830 Tjele, Denmark; iCLIMATE-Interdisciplinary Centre for Climate Change, Aarhus University, DK-8830 Tjele, Denmark; CBIO-Centre for Circular Bioeconomy, Aarhus University, DK-8830 Tjele, Denmark.
| | - M R Weisbjerg
- Department of Animal and Veterinary Sciences, AU-Viborg, Research Centre Foulum, Aarhus University, DK-8830 Tjele, Denmark; iCLIMATE-Interdisciplinary Centre for Climate Change, Aarhus University, DK-8830 Tjele, Denmark; CBIO-Centre for Circular Bioeconomy, Aarhus University, DK-8830 Tjele, Denmark
| | - P Lund
- Department of Animal and Veterinary Sciences, AU-Viborg, Research Centre Foulum, Aarhus University, DK-8830 Tjele, Denmark; iCLIMATE-Interdisciplinary Centre for Climate Change, Aarhus University, DK-8830 Tjele, Denmark; CBIO-Centre for Circular Bioeconomy, Aarhus University, DK-8830 Tjele, Denmark
| | - A Bruhn
- CBIO-Centre for Circular Bioeconomy, Aarhus University, DK-8830 Tjele, Denmark; Department of Ecoscience, Aarhus University, DK-8000 Aarhus C, Denmark
| | - A L F Hellwing
- Department of Animal and Veterinary Sciences, AU-Viborg, Research Centre Foulum, Aarhus University, DK-8830 Tjele, Denmark
| | - M O Nielsen
- Department of Animal and Veterinary Sciences, AU-Viborg, Research Centre Foulum, Aarhus University, DK-8830 Tjele, Denmark; iCLIMATE-Interdisciplinary Centre for Climate Change, Aarhus University, DK-8830 Tjele, Denmark
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Reus AM, Hajek FE, Gruber SM, Plattner S, Hachenberg S, Walleser EA, Aravamuthan SR, Mansfeld R, Döpfer D. Differentiating between metabolic health statuses in Simmental cows and describing related milk fatty acids and relevant associated factors. Transl Anim Sci 2023; 7:txad110. [PMID: 37786425 PMCID: PMC10541854 DOI: 10.1093/tas/txad110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 09/11/2023] [Indexed: 10/04/2023] Open
Abstract
The aim of this observational study was to examine differences in milk fatty acid (FA) concentrations for different metabolic health statuses and for associated factors-specifically to examine with which FA concentrations an increased risk for developing a poor metabolic adaptation syndrome (PMAS) was associated. During weekly visits over 51 wk, blood samples were collected from cows between 5 and 50 days in milk. The farmer collected corresponding milk samples from all voluntary milkings. The analysis was performed on n = 2,432 samples from n = 553 Simmental cows. The observations were assigned to five different cow types (healthy, clever, athletic, hyperketonemic, and PMAS, representing five metabolic health statuses), based on the thresholds of 0.7 mmol/L, 1.2 mmol/L, and 1.4 for the concentrations of β-hydroxybutyrate and nonesterified fatty acids and for the milk fat-to-protein ratio, respectively. Linear regression models using the predictor variables cow type, parity, week of lactation, and milk yield as fixed effects were developed using a stepwise forward selection to test for significant associations of predictor variables regarding FA concentrations in milk. There was a significant interaction term found between PMAS cows and parity compared to healthy cows for C18:1 (P < 0.001) and for C18:0 (P < 0.01). It revealed higher concentrations for PMAS in primiparous and multiparous cows compared to healthy cows, the slope being steeper for primiparous cows. Further, an interaction term was found between PMAS cows and milk yield compared to healthy cows and milk yield for C16:0 (P < 0.05), revealing a steeper slope for the decrease of C16:0 concentrations with increasing milk yield for PMAS compared to healthy cows. The significant associations and interaction terms between cow type, parity, week of lactation, and milk yield as predictor variables and C16:0, C18:0, and C18:1 concentrations suggest excellent opportunities for cow herd health screening during the early postpartum period.
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Affiliation(s)
- Anne M Reus
- Clinic for Ruminants with Ambulatory and Herd Health Services, LMU Munich, 85764 Oberschleissheim, Germany
| | - Franziska E Hajek
- Clinic for Ruminants with Ambulatory and Herd Health Services, LMU Munich, 85764 Oberschleissheim, Germany
| | - Simone M Gruber
- Clinic for Ruminants with Ambulatory and Herd Health Services, LMU Munich, 85764 Oberschleissheim, Germany
| | - Stefan Plattner
- Clinic for Ruminants with Ambulatory and Herd Health Services, LMU Munich, 85764 Oberschleissheim, Germany
| | - Sabrina Hachenberg
- Deutscher Verband für Leistungs- und Qualitätsprüfungen e.V., 53113 Bonn, Germany
| | - Emil A Walleser
- Department of Medical Science, School of Veterinary Medicine, University of Wisconsin–Madison, Madison, WI 53706, USA
| | - Srikanth R Aravamuthan
- Department of Medical Science, School of Veterinary Medicine, University of Wisconsin–Madison, Madison, WI 53706, USA
| | - Rolf Mansfeld
- Clinic for Ruminants with Ambulatory and Herd Health Services, LMU Munich, 85764 Oberschleissheim, Germany
| | - Dörte Döpfer
- Department of Medical Science, School of Veterinary Medicine, University of Wisconsin–Madison, Madison, WI 53706, USA
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Thorsteinsson M, Lund P, Weisbjerg MR, Noel SJ, Schönherz AA, Hellwing ALF, Hansen HH, Nielsen MO. Enteric methane emission of dairy cows supplemented with iodoform in a dose-response study. Sci Rep 2023; 13:12797. [PMID: 37550361 PMCID: PMC10406889 DOI: 10.1038/s41598-023-38149-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 07/04/2023] [Indexed: 08/09/2023] Open
Abstract
Enteric methane (CH4) emission is one of the major greenhouse gasses originating from cattle. Iodoform has in studies been found to be a potent mitigator of rumen CH4 formation in vitro. This study aimed to quantify potential of iodoform as an anti-methanogenic feed additive for dairy cows and investigate effects on feed intake, milk production, feed digestibility, rumen microbiome, and animal health indicators. The experiment was conducted as a 4 × 4 Latin square design using four lactating rumen, duodenal, and ileal cannulated Danish Holstein dairy cows. The treatments consisted of four different doses of iodoform (1) 0 mg/day, (2) 320 mg/day, (3) 640 mg/day, and (4) 800 mg/day. Iodoform was supplemented intra-ruminally twice daily. Each period consisted of 7-days of adaptation, 3-days of digesta and blood sampling, and 4-days of gas exchange measurements using respiration chambers. Milk yield and dry matter intake (DMI) were recorded daily. Rumen samples were collected for microbial analyses and investigated for fermentation parameters. Blood was sampled and analyzed for metabolic and health status indicators. Dry matter intake and milk production decreased linearly by maximum of 48% and 33%, respectively, with increasing dose. Methane yield (g CH4/kg DMI) decreased by maximum of 66%, while up to 125-fold increases were observed in hydrogen yield (g H2/kg DMI) with increasing dose of iodoform. Total tract digestibility of DM, OM, CP, C, NDF, and starch were unaffected by treatments, but large shifts, except for NDF, were observed for ruminal to small intestinal digestion of the nutrients. Some indicators of disturbed rumen microbial activity and fermentation dynamics were observed with increasing dose, but total number of ruminal bacteria was unaffected by treatment. Serum and plasma biomarkers did not indicate negative effects of iodoform on cow health. In conclusion, iodoform was a potent mitigator of CH4 emission. However, DMI and milk production were negatively affected and associated with indications of depressed ruminal fermentation. Future studies might reveal if depression of milk yield and feed intake can be avoided if iodoform is continuously administered by mixing it into a total mixed ration.
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Affiliation(s)
- Mirka Thorsteinsson
- Department of Animal and Veterinary Sciences, AU Viborg - Research Centre Foulum, Aarhus University, 8830, Tjele, Denmark.
- iCLIMATE - Interdisciplinary Centre for Climate Change, Aarhus University, 8830, Tjele, Denmark.
- CBIO - Centre for Circular Bioeconomy, Aarhus University, 8830, Tjele, Denmark.
| | - Peter Lund
- Department of Animal and Veterinary Sciences, AU Viborg - Research Centre Foulum, Aarhus University, 8830, Tjele, Denmark
- iCLIMATE - Interdisciplinary Centre for Climate Change, Aarhus University, 8830, Tjele, Denmark
- CBIO - Centre for Circular Bioeconomy, Aarhus University, 8830, Tjele, Denmark
| | - Martin Riis Weisbjerg
- Department of Animal and Veterinary Sciences, AU Viborg - Research Centre Foulum, Aarhus University, 8830, Tjele, Denmark
- iCLIMATE - Interdisciplinary Centre for Climate Change, Aarhus University, 8830, Tjele, Denmark
- CBIO - Centre for Circular Bioeconomy, Aarhus University, 8830, Tjele, Denmark
| | - Samantha Joan Noel
- Department of Animal and Veterinary Sciences, AU Viborg - Research Centre Foulum, Aarhus University, 8830, Tjele, Denmark
- iCLIMATE - Interdisciplinary Centre for Climate Change, Aarhus University, 8830, Tjele, Denmark
- CBIO - Centre for Circular Bioeconomy, Aarhus University, 8830, Tjele, Denmark
| | - Anna Amanda Schönherz
- Department of Animal and Veterinary Sciences, AU Viborg - Research Centre Foulum, Aarhus University, 8830, Tjele, Denmark
- iCLIMATE - Interdisciplinary Centre for Climate Change, Aarhus University, 8830, Tjele, Denmark
- CBIO - Centre for Circular Bioeconomy, Aarhus University, 8830, Tjele, Denmark
| | - Anne Louise Frydendahl Hellwing
- Department of Animal and Veterinary Sciences, AU Viborg - Research Centre Foulum, Aarhus University, 8830, Tjele, Denmark
- iCLIMATE - Interdisciplinary Centre for Climate Change, Aarhus University, 8830, Tjele, Denmark
- CBIO - Centre for Circular Bioeconomy, Aarhus University, 8830, Tjele, Denmark
| | - Hanne Helene Hansen
- Department of Veterinary and Animal Sciences, University of Copenhagen, 1870, Frederiksberg, Denmark
| | - Mette Olaf Nielsen
- Department of Animal and Veterinary Sciences, AU Viborg - Research Centre Foulum, Aarhus University, 8830, Tjele, Denmark
- iCLIMATE - Interdisciplinary Centre for Climate Change, Aarhus University, 8830, Tjele, Denmark
- CBIO - Centre for Circular Bioeconomy, Aarhus University, 8830, Tjele, Denmark
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Wang W, Lund P, Larsen M, Weisbjerg MR. Effect of nitrate supplementation, dietary protein supply, and genetic yield index on performance, methane emission, and nitrogen efficiency in dairy cows. J Dairy Sci 2023:S0022-0302(23)00367-3. [PMID: 37419744 DOI: 10.3168/jds.2022-22906] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 02/21/2023] [Indexed: 07/09/2023]
Abstract
The objective was to investigate the effect of nonprotein nitrogen source, dietary protein supply, and genetic yield index on methane emission, N metabolism, and ruminal fermentation in dairy cows. Forty-eight Danish Holstein dairy cows (24 primiparous cows and 24 multiparous cows) were used in a 6 × 4 incomplete Latin square design with 4 periods of 21-d duration. Cows were fed ad libitum with the following 6 experimental diets: diets with low, medium, or high rumen degradable protein (RDP):rumen undegradable protein (RUP) ratio (manipulated by changing the proportion of corn meal, corn gluten meal, and corn gluten feed) combined with either urea or nitrate (10 g NO3-/kg of dry matter) as nonprotein nitrogen source. Samples of ruminal fluid and feces were collected from multiparous cows, and total-tract nutrient digestibility was estimated using TiO2 as flow marker. Milk samples were collected from all 48 cows. Gas emission (CH4, CO2, and H2) was measured by 4 GreenFeed units. We observed no significant interaction between dietary RDP:RUP ratio and nitrate supplementation, and between nitrate supplementation and genetic yield index on CH4 emission (production, yield, intensity). As dietary RDP:RUP ratio increased, intake of crude protein, RDP, and neutral detergent fiber and total-tract digestibility of crude protein linearly increased, and RUP intake linearly decreased. Yield of milk, energy-corrected milk, and milk protein and lactose linearly decreased, whereas milk fat and milk urea nitrogen concentrations linearly increased as dietary RDP:RUP ratio increased. The increase in dietary RDP:RUP ratio resulted in a linear increase in the excretion of total purine derivatives and N in urine, but a linear decrease in N efficiency (milk N in % of N intake). Nitrate supplementation reduced dry matter intake (DMI) and increased total-tract organic matter digestibility compared with urea supplementation. Nitrate supplementation resulted in a greater reduction in DMI and daily CH4 production and a greater increase in daily H2 production in multiparous cows compared with primiparous cows. Nitrate supplementation also showed a greater reduction in milk protein and lactose yield in multiparous cows than in primiparous cows. Milk protein and lactose concentrations were lower for cows receiving nitrate diets compared with cows receiving urea diets. Nitrate supplementation reduced urinary purine derivatives excretion from the rumen, whereas N efficiency tended to increase. Nitrate supplementation reduced proportion of acetate and propionate in ruminal volatile fatty acids. In conclusion, no interaction was observed between dietary RDP:RUP ratio and nitrate supplementation, and no interaction between nitrate supplementation and genetic yield index on CH4 emission (production, yield, intensity) was noted. Nitrate supplementation resulted in a greater reduction in DMI and CH4 production, and a greater increase in H2 production in multiparous cows than in primiparous cows. As the dietary RDP:RUP ratio increased, CH4 emission was unaffected and RDP intake increased, but RUP intake and milk yield decreased. Genetic yield index did not affect CH4 production, yield, or intensity.
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Affiliation(s)
- Wenji Wang
- Department of Animal and Veterinary Sciences, AU Viborg-Research Center Foulum, Aarhus University, DK 8830 Tjele, Denmark.
| | - Peter Lund
- Department of Animal and Veterinary Sciences, AU Viborg-Research Center Foulum, Aarhus University, DK 8830 Tjele, Denmark
| | - Mogens Larsen
- Department of Animal and Veterinary Sciences, AU Viborg-Research Center Foulum, Aarhus University, DK 8830 Tjele, Denmark
| | - Martin Riis Weisbjerg
- Department of Animal and Veterinary Sciences, AU Viborg-Research Center Foulum, Aarhus University, DK 8830 Tjele, Denmark.
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Castro M, Matson R, Santschi D, Marcondes M, DeVries T. Association of housing and management practices with milk yield, milk composition, and fatty acid profile, predicted using Fourier transform mid-infrared spectroscopy, in farms with automated milking systems. J Dairy Sci 2022; 105:5097-5108. [DOI: 10.3168/jds.2021-21150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 01/18/2022] [Indexed: 11/19/2022]
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