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. 2022 Jul;50(5):574-590.
doi: 10.1177/01926233221088283. Epub 2022 Apr 6.

Organ Weights in Relation to Age and Sex in Cynomolgus Monkeys (Macaca fascicularis)

Rachel Amato  1 , Jean F Gardin  2 , Janet A Tooze  2 , J Mark Cline  2
Affiliations

Organ Weights in Relation to Age and Sex in Cynomolgus Monkeys (Macaca fascicularis)

Rachel Amato et al. Toxicol Pathol. 2022 Jul.

Abstract

Laboratory animal research is an important contributor to both human and animal medicine. Currently, there is extensive use of cynomolgus monkeys (Macaca fascicularis) in pathology and toxicology research. The purpose of this study was to define reference values for absolute and percentage organ weights in M fascicularis of different ages and sex. Organ weights were obtained from necropsies of 1022 cynomolgus monkeys at the Wake Forest School of Medicine from 1997 to 2018. Distributions of absolute and percentage weights for each organ were described; sex and age groups were compared using analysis of variance. Age effects on percentage of body weights for each organ were analyzed within each sex. Diet effects were also analyzed. This evaluation showed that male body weights and absolute organ weights were greater for all age groups; however, female organ to body weight percentages were greater for most organs. Percentage of organ weight to body weight declined for the adrenals, brain, lung, thyroid and thymus during maturation, whereas percentage weight of pancreas, prostate, testes, and uterus increased. Animals consuming a high-fat, Western-type diet had a lower body weight than animals consuming a carbohydrate-rich chow diet. This information will be useful for further toxicology and pathology studies concerning cynomolgus monkeys.

Keywords: cynomolgus; development; nonhuman primate; organ weights; pathology; sex differences.

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Conflict of interest statement

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figures

Figure 1.
Figure 1.
Absolute body weight (kg) versus age (in years) by sex (N = 992).
Figure 2.
Figure 2.
Absolute weight (grams) versus age (in years) scatter plots for select single and paired organs studied by sex (N = 955 for right adrenal, 959 for left adrenal, 970 for left kidney, 966 for right kidney, 969 for brain, and 975 for heart).
Figure 3.
Figure 3.
Absolute weight (grams) versus age (in years) scatter plots for select single and paired organs studied by sex (N = 924 for left lung, 916 for right lung, 273 for left ovary, 272 for right ovary, 968 for liver, and 926 for pancreas).
Figure 4.
Figure 4.
Absolute weight (grams) versus age (in years) scatter plots for select single and paired organs studied by sex (N = 869 for pituitary, 189 for prostate, and 949 for spleen).
Figure 5.
Figure 5.
Absolute weight (grams) versus age (in years) scatter plots for select single and paired organs studied by sex (N = 227 for left testis, 225 for right testis, 931 for left thyroid, 928 for right thyroid, 192 for thymus, and 572 for uterus).
Figure 6.
Figure 6.
Bar graph of mean organ weight as a percentage of body weight by age category. Statistical significance is relative to the adult group of the same sex. *P < .05. **P < .0001 from analysis of variance. Error bars represent 1 standard error of the mean. For paired organs, statistical significance is comparing subjects to the adult group of the same sex according to anatomical position (i.e., left or right).
Figure 7.
Figure 7.
Bar graph of mean organ weight as a percentage of body weight by age category. Statistical significance is relative to the adult group of the same sex. *P < .05. **P < .0001 from analysis of variance. Error bars represent 1 standard error of the mean. For paired organs, statistical significance is comparing subjects to the adult group of the same sex according to anatomical position (i.e., left or right).
Figure 8.
Figure 8.
Bar graph of mean organ weight as a percentage of body weight by age category. Statistical significance is relative to the adult group of the same sex. *P < .05. **P < .0001 from analysis of variance. Error bars represent 1 standard error of the mean. For paired organs, statistical significance is comparing subjects to the adult group of the same sex according to anatomical position (i.e., left or right).
Figure 9.
Figure 9.
Bar graph of mean organ weight as a percentage of body weight by age category. Statistical significance is relative to the adult group of the same sex. *P < .05. **P < .0001 from analysis of variance. Error bars represent 1 standard error of the mean.
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References

    1. Larson SG. Organ weight scaling in primates. In: Jungers WL, ed. Size and Scaling in Primate Biology (Advances in primatology). Boston, MA: Springer; 1985:91–113.
    1. Kanthaswamy S, Ng J, Satkoski Trask J, et al. The genetic composition of populations of cynomolgus macaques (Macaca fascicularis) used in biomedical research. J Med Primatol. 2013;42(3):120–131. doi:10.1111/jmp.12043. - DOI - PMC - PubMed
    1. Lankau EW, Turner PV, Mullan RJ, Galland GG. Use of nonhuman primates in research in North America. J Am Assoc Lab Anim Sci. 2014;53(3):278–282. - PMC - PubMed
    1. Chellman GJ, Bussiere JL, Makori N, Martin PL, Ooshima Y, Weinbauer GF. Developmental and reproductive toxicology studies in nonhuman primates. Birth Defects Res B Dev Reprod Toxicol. 2009;86(6):446–462. doi:10.1002/bdrb.20216. - DOI - PubMed
    1. Choi K, Chang J, Lee MJ, et al. Reference values of hematology, bio-chemistry, and blood type in cynomolgus monkeys from cambodia origin. Lab Anim Res. 2016;32(1):46–55. doi:10.5625/lar.2016.32.1.46. - DOI - PMC - PubMed

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