Branched chain fatty acid composition of yak milk and manure during full-lactation and half-lactation.
Prostaglandins Leukot Essent Fatty Acids
; 150: 16-20, 2019 11.
Article
em En
| MEDLINE
| ID: mdl-31521006
ABSTRACT
BACKGROUND:
Branched chain fatty acids (BCFA) are bioactive food compounds and are well known to be essential components of human, cow and caprine milk. In Qinghai-Tibet plateau, yaks are domesticated in large numbers and their milk in addition to meat are commercially important to millions of Tibetans and Chinese.OBJECTIVE:
We tested the hypotheses that concentrations of BCFA in yak milk and manure differ between lactation periods and evaluated gene expression levels of certain genes involved in the biosynthesis and elongation of fatty acids.DESIGN:
Fresh milk and manure were collected from each yak and their fatty acid compositions compared with emphasis on BCFA. PARTICIPANTS/SETTING:
Yak milk and manure samples from the full lactation (October, 2015) and half lactation periods (March, 2016) were collected and BCFA levels were analyzed in detail by GC-FID and structures verified by GC-EI-MS/MS. Gene expression studies were carried out by semi-quantitative real time PCR method. STATISTICAL ANALYSES PERFORMED The difference between full lactation and half lactation was tested using student's t-test. Linear regression model was modelled in Excel and its significance was tested by ANOVA. Statistical significance was determined by performing student's t-test for gene expression studies.RESULTS:
BCFA ranged from 3-6% of total fatty acids in yak milk samples. The half-lactation yak milk contained higher levels of BCFA (5.29 ± 0.53) than the full-lactation milk (4.00 ± 0.46). The total BCFA in yak manure was found to be 14.67 ± 1.21, high in anteiso-150 and anteiso-170. ELOVL1 enzyme involved in the elongation of saturated C18 to C26 acyl-CoA substrates and MCAT enzyme involved in the transfer of a malonyl group to the mitochondrial acyl carrier protein are significantly upregulated in full-lactation milk.CONCLUSIONS:
BCFA in yak manure especially anteiso BCFA are positively correlated with yak milk from the same animal, indicating that these BCFA come from dietary sources. Yak milk delivers 777â¯mg BCFA compared to 158â¯mg per cup of whole U.S. dairy milk. QTP herders known to consume up to 2â¯kg of yak yogurt take in an estimated 3,500-5,000â¯mg BCFA per day. We conclude that BCFA intake for yak milk consumers is among the highest known in the world, higher when drawn from half lactating yaks.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Lactação
/
Perfilação da Expressão Gênica
/
Leite
/
Ácidos Graxos
/
Esterco
Limite:
Animals
País/Região como assunto:
Asia
Idioma:
En
Revista:
Prostaglandins Leukot Essent Fatty Acids
Assunto da revista:
ENDOCRINOLOGIA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Estados Unidos