Total body/carcass analysis will reveal absolute amounts of body fat, lean tissue and body water via quantitative magnetic resonance.
Factors Affecting Obesity
Body Composition / Carcass Analysis - C1041 Expand
Energy Expenditure Measurements - C1042 Expand
Oxygen consumption and carbon dioxide production is measured using indirect calorimetry. The Columbus Instruments Oxymax Equal Flow System is an indirect open circuit calorimeter designed to simultaneously measure metabolic performance of multiple subjects that have similar ventilation needs. uses an open circuit calorimetry technique. This system allows sixteen animal cages to be simultaneously monitored. Variables provided by this measurement include VO2, VCO2, RQ, and HEAT.
CLAMS - Activity Measurements - C1043 Expand
This multi-channel activity monitor supports a variety of sensor lengths and configurations. Up to 32 channels are supported providing both ambulatory and total counts for each channel.
Meal Pattern Analysis - Food Intake Procedure - C1044 Expand
A food reservoir is placed on a sensitive balance and introduced to the animal through specially designed cages that prevent defecating/urinating into or spillage of food. Data is generated at intervals of 1 minute to 9999 hours and 59 minutes. Meal patterns can be analyzed with this system by checking the frequency and duration of each meal. Sixteen animal cages can be simultaneously monitored.
CLAMS - Simultaneous Energy Expenditure, Activity, and Food Intake Measurements - C1045 Expand
This service incorporates multiple measurement parameters such as feeding mass/bouts, drinking volume, VO2 and VCO2, etc.
Intestinal lipid absorption in the conscious mouse - lymph fistula - C1051 Expand
This procedure enables the study of the intestinal digestion, absorption and lymphatic transport of dietary lipid in the conscious mouse. By infusing the lipid test meal intraduadenally at a constant rate, the lymphatic lipid output usually reaches a steady rate by the 3rd or 4th hour. Thus, lymphatic lipid output during the 5th or 6th hour represents the amount of lipid transported by the small intestine under steady-state conditions. At the end of the study, both luminal as well as mucosal radioactive lipids can be collected. Thus one can obtain a considerable amount of information regarding the digestion, uptake and mucosal esterification and the lymphatic transport of lipids.
Metabolism of chylomicrons - C1055 Expand
The intestinal lymph duct and duodenum will be surgically cannulated. Chylomicrons are harvested and sized by negative staining. A small sample will be delipidated, and the apoprotein composition will be analyzed by polyacrylamide gel electrophoresis. Labeled CM is injected into mice and the plasma clearance rate is calculated as well as a determination of the uptake by the liver.
Non-invasive measurement of intestinal fat absorption - C1059 Expand
Dietary fat containing 5% sucrose polybehenate, a non-absorbable food additive, is fed in a semi-synthetic diet containing absorbable fat to rodents. The animals eat the diet ad lib for 3 days. Two or more fecal pellets are collected on days 3 and 4. Fat absorption is calculated from the ratios of behenic acid to other fatty acids in the diet and in the feces as analyzed by gas chromatography of fatty acid methyl esters.
Intraperitoneal glucose tolerance - C1070 Expand
Mice will be fasted for 5 hours. A fasting blood sample will be removed from the tail vein and a concentrated solution of glucose injected into the abdominal cavity of the mice through a needle passed through the abdominal skin.. Blood samples will be removed from the tail vein 15, 30, 60 and 120 minutes later. Samples of plasma obtained during the test will be measured for concentrations of glucose and insulin.
Oral glucose tolerance - C1071 Expand
Mice will be fasted for 5 hours. A fasting blood sample will be removed from the tail vein and a concentrated solution of glucose infused into the stomach of the mice through a biofeed needle passed through the mouth. Blood samples will be removed from the tail vein 15, 30, 60 and 120 minutes later. Samples of plasma obtained during the test will be measured for concentrations of glucose and insulin.
Insulin tolerance test - C1072 Expand
Mice will be fasted for 5 hours. A fasting blood sample will be removed from the tail vein and insulin (0.5mU/g) will be injected into the abdominal cavity. Blood samples will be removed from the tail vein 15, 30, 45 and 60 minutes later. Samples of plasma obtained during the test will be measured for concentrations of glucose and insulin.
Necropsy (tissue collection) - C1103 Expand
Animals will be anesthetized and tissues harvested as requested. These tissue will be frozen in liquid nitrogen or fixed.
Telemetry - Cardiac parameters (BP, HR, Pulse Pressure, Activity) - C1106 Expand
Adult mice will be anesthetized and the PA-C10 telemetry device (available from Data Sciences International) will be placed SQ and anchored with suture to the abdominal muscle wall in a location that will not hinder the animal’s mobility. The catheter tip will be inserted into the animal’s left carotid artery and advanced so that it enters the aorta. Animals will be allowed to recover for at least seven days before the onset of testing. The PA-C10 device will measure physiological variables such as blood pressure, heart rate, pulse pressure and activity.