Table 30. — Kidney and liver weights of fasted and nonfasted rats losing weight at different ages on SPM, 



SPB, and SPPB diets 









Kidney weight 



Liver weight ' 



Condition, weight loss, age (days), and 



Rats 



Average 

 age 











diet 

















Average 



Range 



Average 



Range 



Fasted 















Losing less than 100 grams: 















200 to 499 days old: 



Number 



Days 



Grams 



Grams 



Grams 



Grams 



SPM 



5 



350 



1. 63 



0. 99- 2. 60 



13. 4 (4) 



7. 7 -17. 2 



SPB... 



3 

 17 



268 

 330 



1. 22 

 2.26 



. 85- 1. 47 

 . 56- 7. 41 



9.9 

 15. 2 



7. 3 -11. 9 



SPPB 



5. -21. 5 



500 davs and older: 















SPM 



5 



528 



2. 50 



1. 93- 4. 35 



16. 2 



14. 7 -18. 1 



SPB.._ 



4 

 5 



651 



586 



2. 52 

 3.25 



1. 63- 4. 53 



1. 38- 7. 09 



15. 6 

 18. 2 



12. 7 -20. 2 

 11. -24. 7 



SPPB 



Losing more than 100 grams: 



200 to 499 days old: 















SPM 



1 



362 



1. 10 



1. 10 



9. 63 



9. 6 



SPB 



1 



461 



1.51 



1.51 



12. 5 



12. 5 



SPPB 















500 davs and older: 















SPM 



3 



4 

 4 



796 

 630 

 531 



2.97 

 2. 82 

 3.80 



1. 63- 5. 53 



1. 50- 3. 48 



2. 12- 5. 78 



13. 

 12. 2 



19. 4 (3) 



10. 1 -15. 6 



11. -14. 8 



12. 5 -28. 8 



SPB... 



SPPB 



Nonfasted 















Losing less than 100 grams: 















200 to 499 davs old: 















SPM 



7 



354 



2. 67 



1. 30- 6. 2S 



18.2 



14. 7 -22. 3 



SPB 



7 



312 



2.05 



. 96- 3. 70 



16.5 (6) 



8. 7 -27. 7 



SPPB 



6 



373 



5.50 



1. 52-15. 8 



22. 5 



9. 8 -33. 1 



500 days and older: 















SPM 



2 



728 



2.23 



1. 83, 2. 63 



19. 4 



18. 0, 20. 8 



SPB 



3 



696 



2. 53 



1. 64- 3. 36 



22.8 



15. 2 -31. 3 



SPPB 



6 



643 



1.98 



1. 77- 2. 28 



19.4 



15. 2 -25. 8 



Losing more than 100 grams: 















200 to 499 days old: 















SPM 



5 



433 



4.46 



1. 48- 8. 68 



16.5 



12. -21. 8 



SPB 



5 



435 



4. 93 



3. 01- 6. 40 



16. 



13. 9 -18. 1 



SPPB 



5 



397 



6.06 



3. 84- 7. 99 



22. 2 



11. S -29. 2 



500 davs and older: 















SPM 



7 



706 



2.94 



1. 58- 4. 41 



15. 1 (5) 



11. 4 -18. 3 



SPB 



9 



609 



5.08 



2. 00- 8. 03 



16. 3 



13. 4 -21. 4 



SPPB 



4 



606 



5. 20 



3. 89- 6. 25 



18.4 



14. 2 -21. 9 



1 Numbers in parentheses indicate when number of livers do not correspond to number of kidneys. 



have generally been observed in rats fed SPE diet 

 were also obtained with all of the supplemented 

 diets. The kidneys from rats fed the diets supple- 

 mented with vitamin B 6 tended to be smaller, on 

 the average, than those from rats fed the unsup- 

 plemented diet, paralleling the histological find- 

 ings. The largest average kidney weights were 

 obtained when the diets were supplemented with 

 vitamin B !2 or with cholesterol. Although these 

 supplements were without effect on the lifespan 

 of these animals, there is some indication that they 

 may have influenced the metabolic processes in- 

 volved in the utilization of these diets. Consider- 

 ing the wide range of values obtained in moribund 

 rats, however, data uncomplicated by excessive 

 weight loss are needed to establish the significance 

 of the trends observed. 



Rats fed diets containing 8 or 16 percent 

 HVO, lard, or butter. — The kidney and liver 



weights for rats fed diets in which the kind and/or 

 level of fat was varied are summarized in table 32. 

 Data from animals that were maintaining weight 

 are limited to a group of five nonfasted rats fed 

 SP 8 HVO diet and the corresponding results 

 with the littermates fed SP S lard. No significant 

 differences in the liver or kidney weights of these 

 young rats were obtained. The results for sick 

 or moribund rats have been separated on the basis 

 of weight loss before sacrifice. When weight loss 

 was less than 100 grams, the kidneys from rats 

 fed diets containing hydrogenated vegetable oil 

 at either the 8- or 16-percent level tended to be 

 smaller than those from rats fed diets containing 

 8 or 16 percent lard or butter. When weight loss 

 exceeded 100 grams, the results for fasted and for 

 nonfasted rats have been combined because of the 

 smaU differences usually observed in these two 

 groups of animals. The kidneys from this latter 



43 



