Lactational performance of dairy cows in response to supplementing N-acetyl-l-methionine as source of rumen-protected methionine

The Authors. Published by Elsevier Inc. and Fass Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)..

The objective of this experiment was to evaluate the effects of supplementing a rumen-protected source of Met, N-acetyl-l-methionine (NALM), on lactational performance and nitrogen metabolism in early- to mid-lactation dairy cows. Sixty multiparous Holstein dairy cows in early lactation (27 ± 4.3 d in milk, SD) were assigned to 4 treatments in a randomized complete block design. Cows were blocked by actual milk yield. Treatments were as follows: (1) no NALM (control); (2) 15 g/d of NALM (NALM15); (3) 30 g/d of NALM (NALM30); and (4) 45 g/d of NALM (NALM45). Diets were formulated using a Cornell Net Carbohydrate and Protein System (CNCPS) v.6.5 model software to meet or exceed nutritional requirements of lactating dairy cows producing 42 kg/d of milk and to undersupply metabolizable Met (control) or supply incremental amounts of NALM. The digestible Met (dMet) supply for control, NALM15, NALM30, and NALM45 were 54.7, 59.8, 64.7, and 72.2 g/d, respectively. The supply of dMet was 88, 94, 104, and 115% of dMet requirement for control, NALM15, NALM30, and NALM45, respectively. Milk yield data were collected, dry matter intake (DMI) was measured daily, and milk samples were collected twice per week for 22 wk. Blood, ruminal fluid, urine, and fecal samples were collected during the covariate period and during wk 4, 8, and 16. Data were analyzed using the GLIMMIX procedure of SAS (SAS Institute) using covariates in the model for all variables except body weight. Linear, quadratic, and cubic contrasts were also tested. Treatments did not affect DMI, milk yield, and milk component concentration and yield; however, feed efficiency expressed as milk yield per DMI and 3.5% fat-corrected milk per DMI were quadratically affected, with greater response observed for NALM15 and NALM30 compared with control. Acetate proportion linearly increased, whereas propionate proportion linearly decreased with NALM supplementation. Blood urea nitrogen linearly decreased with NALM supplementation. Total plasma essential AA concentrations were quadratically affected, as greater values were observed for control and NALM45 than other treatments. Plasma Met concentration was quadratically affected as lower levels were observed with NALM15, whereas Met concentrations increased with NALM45 compared with control. Nitrogen utilization efficiency and apparent total-tract nutrient digestibility were not affected by treatment. Supplementation of NALM at 15 or 30 g/head per day resulted in the greatest improvements in feed efficiency without affecting N metabolism of early- to mid-lactation dairy cows.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:105

Enthalten in:

Journal of dairy science - 105(2022), 3 vom: 01. März, Seite 2301-2314

Sprache:

Englisch

Beteiligte Personen:

Amaro, F X [VerfasserIn]
Kim, D [VerfasserIn]
Restelatto, R [VerfasserIn]
Carvalho, P [VerfasserIn]
Arriola, K [VerfasserIn]
Duvalsaint, E J C [VerfasserIn]
Cervantes, A P [VerfasserIn]
Jiang, Y [VerfasserIn]
Agarussi, M C N [VerfasserIn]
Silva, V P [VerfasserIn]
Adesogan, A T [VerfasserIn]
Ferraretto, L F [VerfasserIn]
Staples, C R [VerfasserIn]
Eun, J-S [VerfasserIn]
Moon, J O [VerfasserIn]
Vyas, D [VerfasserIn]

Links:

Volltext

Themen:

AE28F7PNPL
Amino acid profile
Feed efficiency
Journal Article
Metabolizable methionine
Methionine
N-acetyl-l-methionine
Randomized Controlled Trial, Veterinary

Anmerkungen:

Date Completed 22.02.2022

Date Revised 31.05.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.3168/jds.2021-21068

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM334911540