L-lactate utilization by dairy goats

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1984

OSTI ID:5220637

Rodriguez, N R

Three Toggenberg goats were used to investigate utilization of L-lactate as substrate for lipogenesis and gluconeogenesis. Objectives were: (1) to determine the extent lactate could be used for body and milk fat synthesis; (2) to estimate contribution of lactate to glucose synthesis; (3) to assess differences in these measurements during early lactation, mid-lactation and the dry period; and (4) to observe differences in labeling of glycerol and free fatty acid (FFA) fractions in body and milk fat 7 days post-infusion of isotopes. Goats were fed in metabolism crates a 70% concentrate ration in hourly increments to meet individual requirements. After a pulse dose, U-/sup 14/C-lactate (34 uCi/hr) and 6-/sup 3/H-Glucose (100 uCi/hr) was infused via jugular cannula for 8 hours. Blood an milk were sampled hourly beginning 3 and 3.5 hours, respectively, after the pulse dose. Body fat was biopsied after the infusion (Day 0) and one week post-infusion (Day 7). Plasma glucose and lactate concentrations were greater in early 70.4 and 7.7 mg/dl, respectively) compared to mid-lactation (50.8 and 5.9 gm/dl). Mid-lactation and dry period values were similar. Glucose turnover differed for early and mid-lactation and the dry period (141, 86, and 70 mmol/hr, respectively). Percentage of glucose derived from lactate tended to decrease through lactation into the dry period (28% vs 10%). Plasma lactate turnover was greater during lactation as opposed to the dry period (124 and 35 mmol/hr). During early lactation a greater proportion of lactate was incorporated into glucose than during either mid-lactation or the dry period.

• Research Organization: West Virginia Univ., Morgantown (USA)
• OSTI ID: 5220637
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADIPOSE TISSUE
ALDEHYDES
ANIMAL TISSUES
ANIMALS
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL MATERIALS
BIOPSY
BIOSYNTHESIS
BLOOD
BODY
BODY FLUIDS
CARBOHYDRATES
CARBON 14 COMPOUNDS
CARBOXYLIC ACID SALTS
CONNECTIVE TISSUE
DIAGNOSTIC TECHNIQUES
DOMESTIC ANIMALS
FOOD
GLUCOSE
GOATS
HEXOSES
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
LACTATES
LACTATION
MAMMALS
MATERIALS
MILK
MONOSACCHARIDES
ORGANIC COMPOUNDS
REACTION KINETICS
RUMINANTS
SACCHARIDES
SYNTHESIS
TISSUES
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES