Nitrogen Intake and Its Partition on Urine, Dung and Products of Dairy and Beef Cattle in Chile
Abstract
:1. Introduction
2. Materials and Methods
2.1. Data Collection
2.2. Description of Database
2.3. Equations Used for N Partitioning
2.4. Quality Control
2.5. Statistical Analysis
3. Results and Discussion
3.1. Summary of Collated Data
3.2. Distribution of Data Collated for N Partitioning
3.3. Effect of Type of Animal, System and DIM on N Partitioning
3.4. Variables Influencing N Partitioning of Dairy Cattle
3.5. Implication of Database
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Parameter | Equation | Reference | |
---|---|---|---|
1 | Total N intake (TNI) | TNI (g N/d) = ((% CP/6.25) × DMI)/100 | [24] |
Dairy Cattle | |||
2 | Milk N (MN) | MN (g N/d) = Milk yield × (% CP in milk/6.38)/100 | [17,25,26] |
3 | Total N excretion (TNE) | TNE (g N/d) = TNI − MN | - |
4 | Nitrogen use efficiency (NUE) | NUE (%) = MN/TNI × 100 | [17,24,26] |
5 | Urinary N excretion (UNE) | UNE (g N/d) = 104 + 0.855 × TNI – 13.2 × DMI − 6.8 × (ME × 4.184) | [27] |
6 | Dung N excretion (DNE) | DFE (g N/d) = TNI − (UNE + MN) | [24,28] |
Beef cattle | |||
7 | Nitrogen use efficiency (NUE) | NUE (%) = (TNI − TNE)/TNI × 100 | [16] |
8 | Urinary N excretion (UNE) | UNE (g N/d) = −71.2 + 0.265 × TNI + 3.76 × CP + 0.468 × BW0.75 | [22] |
9 | Dung N excretion (DNE) | DNE (g N/d) = 0.506 + 0.352 × TNI | [22] |
10 | Total N excretion (TNE) | TNE (g N/d) = UNE + DNE | - |
Variables | Nitrogen Use Efficiency | |
---|---|---|
Count | Percent (%) | |
Dairy Cattle | ||
System | ||
Grazing | 16 | 13.4 |
Grazing and supplementation | 103 | 86.6 |
Season | ||
Autumn | 38 | 31.9 |
Spring | 66 | 55.5 |
Summer | 13 | 10.9 |
Winter | 2 | 1.7 |
Beef Cattle | ||
System | ||
Grazing | 5 | 17.9 |
Grazing and supplementation | 1 | 3.5 |
Feedlot | 22 | 78.6 |
Season | ||
Autumn | 3 | 10.7 |
Spring | 16 | 57.2 |
Summer | 2 | 7.1 |
Winter | 7 | 25 |
Variables 1 | Dairy Cattle | Beef Cattle | ||||||
---|---|---|---|---|---|---|---|---|
N 2 | Mean | Q1 3 | Q3 4 | N | Mean | Q1 | Q3 | |
Total N intake, g N/d | 117 | 511.1 | 436.8 | 566.1 | 28 | 231.5 | 177.6 | 256.4 |
NUE, % | 117 | 24.7 | 21.8 | 26.5 | 28 | 24.6 | 21.3 | 27 |
Urine N, g N/d | 117 | 243.1 | 194.7 | 284 | 28 | 94.82 | 62.76 | 124.5 |
Dung N, g N/d | 115 | 143.2 | 125.1 | 157.4 | 28 | 81.5 | 63 | 90.8 |
Milk yield, kg milk/d | 119 | 24.6 | 22 | 28.4 | - | - | - | - |
Milk Fat, % | 117 | 3.8 | 3.6 | 4 | - | - | - | - |
Milk Protein, % | 117 | 3.3 | 3.1 | 3.4 | - | - | - | - |
Milk N, g/d | 117 | 125 | 110.2 | 143 | - | - | - | - |
Milk Urea, mmol/L | 79 | 6 | 5 | 6.8 | - | - | - | - |
Blood urea plasma, mmol/L | 63 | 6.2 | 5.3 | 7.6 | - | - | - | - |
Propionate, mmol/L | 27 | 16.2 | 13.8 | 18.2 | 2 | 5.7 | 5.47 | 5.99 |
Acetate, mmol/L | 27 | 52.3 | 43.3 | 60.5 | 2 | 1.02 | 9.26 | 11.21 |
Butyrate, mmol/L | 27 | 10.6 | 8.6 | 11.9 | 2 | 1.94 | 1.86 | 2.01 |
Rumen Ammonia, mmol/L | 29 | 8.6 | 6.1 | 10.4 | - | - | - | - |
NFC intake | 94 | 4.7 | 3.8 | 5.6 | 2 | 0.71 | 0.692 | 0.72 |
NFC/CP ratio | 94 | 1.5 | 1.1 | 1.8 | 2 | 0.67 | 0.56 | 0.78 |
Body weight, kg | 123 | 535 | 514 | 554 | 38 | 415 | 367 | 460 |
Variables 1 | Beef Cattle | Dairy Cattle | p-Value |
---|---|---|---|
N intake. g N/d | 227 ± 27 | 447 ± 21.1 | <0.01 |
NUE. % | 17.9 ± 1.62 | 27 ± 1.13 | <0.01 |
Urine N. g N/d | 101 ± 25.5 | 199 ± 14.5 | <0.01 |
Dung N. g N/d | 94.4 ± 10.9 | 126.6 ± 6.9 | 0.02 |
Total N excretion. g N/d | 192 ± 27.5 | 327 ± 19.2 | <0.01 |
N excretion per 1000 kg BW/d | 0.37 ± 0.06 | 0.63 ± 0.04 | <0.01 |
N in milk. g N/d | - | 117 ± 4.31 | - |
N excreted/kg milk | - | 16.4 ± 0.64 | - |
N 2 Intake g N/d | NUE 3 % | N Milk g N/d | Urinary N Excretion g N/d | Dung N Excretion g N/d | |
---|---|---|---|---|---|
System | |||||
All grazing | 509 ± 20 | 22.6 ± 0.99 | 111 ± 4.52 | 254 ± 13.8 | 144 ± 6.37 |
Grazing and supplementation | 497 ± 17 | 25.6 ± 0.78 | 126 ± 3.97 | 231 ± 11.9 | 140 ± 4.22 |
p-value | 0.35 | <0.01 | <0.01 | <0.01 | 0.45 |
Days in milk | |||||
Early (0–100 d) | 512 ± 18.7 | 25.7 ± 0.92 | 129 a ± 3.87 | 243 ± 13.4 | 143 ± 4.86 |
Medium (100–200 d) | 457 ± 39.7 | 23.7 ± 1.95 | 106 b ± 8.35 | 217 ± 28.3 | 135 ± 10.36 |
Late (>200 d) | 480 ± 36.5 | 23.6 ± 1.93 | 111 ab ± 7.96 | 215 ± 25.7 | 137 ± 10.9 |
p-value | 0.36 | 0.42 | 0.01 | 0.46 | 0.71 |
Season 1 | |||||
Autumn | 456 ± 28.7 | 23.3 ± 1.3 | 104 b ± 4.59 | 211 ± 21 | 138 ± 7.55 |
Spring | 534 ± 21.8 | 26.6 ± 0.99 | 139 a ± 3.4 | 254 ± 16 | 142 ± 5.76 |
Summer | 457 ± 43.2 | 23.4 ± 1.98 | 105 b ± 7 | 214 ± 31.6 | 140 ± 11.72 |
p-value | 0.07 | 0.1 | <0.01 | 0.22 | 0.89 |
N 1 Intake g N/d | NUE 2 % | Urinary N Excretion g N/d | Dung N Excretion g N/d | N Excreted per 1000 kg BW 3 | |
---|---|---|---|---|---|
System | |||||
All grazing | 328 ± 31.9 | 16.1 ± 2.39 | 153 ± 13.2 | 115 ± 11.35 | 0.51 ± 0.07 |
Feedlot | 203 ± 25.4 | 26.8 ± 1.87 | 79.1 ± 10.4 | 71.2 ± 9.09 | 0.31 ± 0.06 |
p-value | <0.01 | <0.01 | <0.01 | <0.01 | <0.01 |
Season | |||||
Autumn | 182 ± 101 | 17.7 ± 5.08 | 89 ± 49.2 | 64.7 ± 37.1 | 0.54 ± 0.21 |
Winter | 173 ± 70.5 | 25.3 ± 3.4 | 67.3 ± 34.2 | 61.3 ± 26 | 0.25 ± 0.15 |
Spring | 275 ± 49 | 25.2 ± 2.39 | 113 ± 24.1 | 95.8 ± 18.2 | 0.37 ± 0.11 |
Summer | 178 ± 77 | 25.0 ± 4.4 | 69.7 ± 34.2 | 63.3 ± 28 | 0.26 ± 0.16 |
p-value | 0.63 | 0.62 | 0.73 | 0.69 | 0.74 |
Variable 1 | Estimate | S.E 2 | p-Value |
---|---|---|---|
Nitrogen use efficiency 3 | |||
Intercept | 16.7 | 3.6 | <0.01 |
Milk yield (kg/d) | 0.45 | 0.08 | <0.01 |
NFC/CP ratio 4 | 4.12 | 0.7 | <0.01 |
Milk urea nitrogen (mmol/L) | −0.47 | 0.27 | 0.09 |
ADF intake (kg/d) | −1.65 | 0.5 | <0.01 |
Urine N excretion 5 | |||
Intercept | 84.85 | 46.7 | 0.07 |
Milk urea nitrogen (mmol/L) | 16.05 | 4.7 | <0.01 |
Milk yield (kg/d) | 4.9 | 1.6 | <0.01 |
NFC intake (g/d) | −14.4 | 4.39 | <0.01 |
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Beltran, I.E.; Calvache, I.; Cofre, R.; Salazar, F.; Keim, J.P.; Morales, A.; Pulido, R.G.; Alfaro, M. Nitrogen Intake and Its Partition on Urine, Dung and Products of Dairy and Beef Cattle in Chile. Agronomy 2022, 12, 15. https://doi.org/10.3390/agronomy12010015
Beltran IE, Calvache I, Cofre R, Salazar F, Keim JP, Morales A, Pulido RG, Alfaro M. Nitrogen Intake and Its Partition on Urine, Dung and Products of Dairy and Beef Cattle in Chile. Agronomy. 2022; 12(1):15. https://doi.org/10.3390/agronomy12010015
Chicago/Turabian StyleBeltran, Ignacio E., Ivan Calvache, Rocio Cofre, Francisco Salazar, Juan P. Keim, Alvaro Morales, Ruben G. Pulido, and Marta Alfaro. 2022. "Nitrogen Intake and Its Partition on Urine, Dung and Products of Dairy and Beef Cattle in Chile" Agronomy 12, no. 1: 15. https://doi.org/10.3390/agronomy12010015
APA StyleBeltran, I. E., Calvache, I., Cofre, R., Salazar, F., Keim, J. P., Morales, A., Pulido, R. G., & Alfaro, M. (2022). Nitrogen Intake and Its Partition on Urine, Dung and Products of Dairy and Beef Cattle in Chile. Agronomy, 12(1), 15. https://doi.org/10.3390/agronomy12010015