Document Detail

Changes in chemical composition of Alxa bactrian camel milk during lactation.
MedLine Citation:
PMID:  16162513     Owner:  NLM     Status:  MEDLINE    
Changes in chemical composition of Alxa bactrian camels reared in Inner Mongolia (China) during lactation were investigated. Colostrum and milk samples from 10 nomadic female camels in their first season of lactation were collected periodically from parturition until 90 d postpartum (PP). The average contents of gross composition were 14.23% protein, 4.44% lactose, 0.27% fat, 0.77% ash, and 20.16% total solids in colostrum at 2 h PP, and the respective mean values were 3.55, 4.24, 5.65, 0.87, and 14.31% for regular milk on d 90. A 15-fold increase was shown in fat content during the first 24 h, whereas a sharp decrease was shown during the first 12 h of lactation in protein, ash, and total solids contents. Variation in lactose content was small (4.24 to 4.71%) throughout the study period. Total N, nonprotein N, casein N, and whey protein N were found to be 2.23, 0.06, 0.86, and 1.31 g/100 mL for the colostrum at 2 h PP; and 0.56, 0.04, 0.45, and 0.07 g/100 mL for the milk at 90 d PP. Percentages of caseins increased steadily, whereas whey proteins declined gradually until 3 mo of lactation. Gas liquid chromatography analysis of milk fat showed that the content of even-numbered saturated fatty acids (C12:0-C18:0) in camel colostrum (2 h to 7 d PP) was lower than that of regular milk (15 to 90 d PP). The predominant saturated fatty acids were C14:0, C16:0, and C18:0, regardless of the stage of lactation. There was a considerable level of polyunsaturated fatty acids (mainly C18:1) in Alxa camel's milk fat. The levels of Ca, P, Na, K, and Cl were 222.58, 153.74, 65.0, 136.5, and 141.1 mg/100 g, respectively, at 2 h PP; the values of the minerals were 154.57, 116.82, 72.0, 191.0, and 152.0 mg/100 g, respectively, for the regular milk on d 90. The levels of vitamins A, C, E, B1, B2, B6, and D were 0.97, 29.60, 1.45, 0.12, 1.24, 0.54 mg/L, and 640 IU/L, respectively, in Alxa camel milk at 90 d PP. Vitamin A and C contents were higher and vitamins E and B1 were lower than those in colostrum. Sodium dodecyl sulfate-PAGE and densitometry results demonstrated that Alxa camel colostrum is rich in immunoglobulins, serum albumin, and 2 unknown fractions, which are reduced in amount (%) within 2 d of lactation. It seems that there is lack of beta-lactoglobulin in Alxa camel milk, whereas casein and -lactalbumin start at a low level and increase gradually until they reach their regular levels in the milk.
H Zhang; J Yao; D Zhao; H Liu; J Li; M Guo
Related Documents :
18629683 - Ghrelin and orotic acid increased in subclinical mastitis.
15290973 - Relative acidifying activity of anionic salts commonly used to prevent milk fever.
15447903 - Absorption, excretion, and distribution of dietary antioxidant betalains in ldls: poten...
Publication Detail:
Type:  Comparative Study; Journal Article    
Journal Detail:
Title:  Journal of dairy science     Volume:  88     ISSN:  1525-3198     ISO Abbreviation:  J. Dairy Sci.     Publication Date:  2005 Oct 
Date Detail:
Created Date:  2005-09-15     Completed Date:  2006-03-06     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  2985126R     Medline TA:  J Dairy Sci     Country:  United States    
Other Details:
Languages:  eng     Pagination:  3402-10     Citation Subset:  IM    
College of Food Science and Engineering, Inner Mongolia Agriculture University, Hohhot, Inner Mongolia, China.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Camels / physiology*
Caseins / analysis
Colostrum / chemistry
Fats / analysis
Fatty Acids / analysis
Immunoglobulins / analysis
Lactalbumin / analysis
Lactoglobulins / analysis
Lactose / analysis
Milk / chemistry*
Milk Proteins / analysis
Minerals / analysis
Nitrogen / analysis
Postpartum Period
Serum Albumin / analysis
Vitamins / analysis
Reg. No./Substance:
0/Caseins; 0/Fats; 0/Fatty Acids; 0/Immunoglobulins; 0/Lactoglobulins; 0/Milk Proteins; 0/Minerals; 0/Serum Albumin; 0/Vitamins; 0/whey protein; 63-42-3/Lactose; 7727-37-9/Nitrogen; 9013-90-5/Lactalbumin

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Effects of Pseudomonas fluorescens M3/6 bacterial protease on plasmin system and plasminogen activat...
Next Document:  Effects of two types of emulsifying salts on the functionality of nonfat pasta filata cheese.