University:
Sam Houston State University
Course:
BIOL 2413 | General Zoology
Academic year:

2019
Views:

286

Pages:

11
Author:

K Moody

Part 3  The amount of lipid increases, as a percentage of the tissue weight, in older animals  As we enter the fattening stage of the growth curve we slow growth of other tissues, leaving more energy to be stored as fats.  Fat  depots develop at different times Some are larger than others based on which developed first  Intramuscular adipocytes may account for 50% of the total NUMBER of adipocytes, but may represent only 10% of the total LIPID.  Monogastric vs. Ruminants  Microbes cause hydrogenation of fatty acids that enter the rumen  Converts unsaturated fatty acids to saturated fatty acids.  In the 1950’s and 60’s genetic lines of pigs may have had 5 cm of back fat at market weight  Now pigs may have a few mm at market weight  Testosterone inhibits lipid deposition.  Increased fatness seen in females is associated with a greater SIZE of adipocytes rather than a greater number.  Due to estrogenic hormones  In addition to sex hormones, Leptin plays a major role in nutrient partitioning  Leptin is associated with feed intake and appetite, and are seen in higher levels in obese animals.  High fat diets depress FA synthesis while low fat diets increase de novo synthesis rates.  The presence of high amount of marbling generally indicates the animal was fed on a high plane of nutrition.  Diets with amino acid deficiencies often result in increased lipogenesis due to the excess energy  Animals exposed to low temperature will mobilize adipose tissue to support heat production.  At high temperatures feed intake is depressed so as to inhibit heat producing processes.  Know the four locations fat is deposited  Explain adipogenesis  Explain lipogenesis  Compare and contrast the different factors affecting lipid metabolism