Do Frequent Lactation Periods in Laboratory Rat Colonies Have a Negative Effect on Mothers' Care and Feeding of Themselves and Their Offspring?

Öz

Laboratory rats are the second most preferred mammal species in experimental research. Do the frequent lactation periods of the female rats used in production in this study negatively affect the care of the offspring and themselves? For this purpose, the care of mother rats from a conventional outbred Wistar Albino rat colony for themselves and their offspring was monitored in two consecutive lactation periods. Mother rats successfully raised all their offspring in two lactation periods, mothers spent 85% of their daily life in the early phase of the two lactation periods (Post Natal-PN 1-8 days), 60% of their daily life in the mid-lactation phase (PN 9-18 days) and 60% of their daily life in the late lactation phase (PN 19-23 days) have been found to spend 30% of their daily lives with their offspring. While there was a significant difference in terms of the times that mother rats were with their babies in the early, middle, and late stages of the lactation period, the time they were separated from their babies and the frequency of separation (p< .001), no significant difference was found when the same stages of the two lactation periods were compared with each other (p> .05). Live weight change, feed consumption, and water consumption changes of mother rats in two lactation periods were compared and no significant difference was found. It was concluded that there was no negative effect on the care of mother rats and their offspring during frequent lactation periods.

Anahtar Kelimeler

• Dry period
• Frequent lactation period
• Laboratory mother rat
• Offspring care

Do Frequent Lactation Periods in Laboratory Rat Colonies Have a Negative Effect on Mothers' Care and Feeding of Themselves and Their Offspring?

Öz

Laboratory rats are the second most preferred mammal species in experimental research. Do the frequent lactation periods of the female rats used in production in this study negatively affect the care of the offspring and themselves? For this purpose, the care of mother rats from a conventional outbred Wistar Albino Rat colony for themselves and their offspring was monitored in two consecutive lactation periods. Mother rats successfully raised all their offspring in two lactation periods, mothers spent 85% of their daily life in the early phase of the two lactation periods (Post Natal-PN1-8 days), 60% of their daily life in the mid-lactation phase (PN9-18 days) and 60% of their daily life in the late lactation phase (PN19). -23 days) have been found to spend 30% of their daily lives with their offspring. While there was a significant difference in terms of the times that mother rats were with their babies in the early, middle and late stages of the lactation period, the time they were separated from their babies and the frequency of separation (pF<0.001), no significant difference was found when the same stages of the two lactation periods were compared with each other (p>0.05). Live weight change, feed consumption and water consumption changes of mother rats in two lactation periods were compared and no significant difference was found. It was concluded that there was no negative effect on the care of mother rats and their offspring during frequent lactation periods.

Anahtar Kelimeler

• Laboratory mother rat
• Self-care of mothers
• Offspring care
• Frequent lactation period
• Dry period

Etik Beyan

Although there was no procedure that would harm the welfare of the mother rats followed in this study, study approval was received from the DEU Animal Experiments Local Ethics Committee with protocol approval number 09/2022.

Kaynakça

1. Ballard, O., & Morrow, A. L. (2013). Human milk composition. Pediatric Clinics of North America, 60(1), 49-74. https://doi.org/10.1016/j.pcl.2012.10.002.
2. Barker D. J. (1990). The fetal and infant origins of adult disease. BMJ (Clinical research ed.), 301(6761), 1111. https://doi.org/10.1136/bmj.301.6761.1111.
3. Bartlett, D., & Piper, M. C. (1993). Neuromotor development of preterm infants through the first year of life. Physical & Occupational Therapy in Pediatrics, 12(4), 37–55. https://doi.org/10.1080/J006v12n04_04.
4. Bauman, D. E., & Bruce Currie, W. (1980). Partitioning of nutrients during pregnancy and lactation: A review of mechanisms involving homeostasis and homeorhesis. Journal of Dairy Science, 63(9), 1514-1529. https://doi.org/10.3168/jds.S0022-0302(80)83111-0.
5. Bautista, C. J., Bautista, R. J., Montaño, S., Reyes-Castro, L. A., Rodriguez-Peña, O. N., Ibáñez, C. A., Nathanielsz, P. W., & Zambrano, E. (2019). Effects of maternal protein restriction during pregnancy and lactation on milk composition and offspring development. British Journal of Nutrition, 122(2), 141-151. https://doi.org/10.1017/S0007114519001120.
6. Bautista, C. J., Boeck, L., Larrea, F., Nathanielsz, P. W., & Zambrano, E. (2008). Effects of a maternal low protein isocaloric diet on milk leptin and progeny serum leptin concentration and appetitive behavior in the first 21 days of neonatal life in the rat. Pediatric Research, 63(4), 358-363. https://doi.org/10.1203/01.pdr.0000304938.78998.21
7. Fields, D. A., Schneider, C. R., & Pavela, G. (2016). A narrative review of the associations between six bioactive components in breast milk and infant adiposity: Heterogeneity of Breast Milk. Obesity, 24(6), 1213-1221. https://doi.org/10.1002/oby.21519.
8. Forsdahl, A. (1977). Are poor living conditions in childhood and adolescence an important risk factor for arteriosclerotic heart disease?. Journal of Epidemiology & Community Health, 31(2), 91-95. https://doi.org/10.1136/jech.31.2.91.

9. Gunderson, E. P., Lewis, C. E., Lin, Y., Sorel, M., Gross, M., Sidney, S., Jacobs, D. R., Shikany, J. M., & Quesenberry, C. P. (2018). Lactation duration and progression to diabetes in women across the childbearing years: The 30-year cardia study. JAMA Internal Medicine, 178(3), 328. https://doi.org/10.1001/jamainternmed.2017.7978.
10. Li, C., Jenkins, S., Considine, M. M., Cox, L. A., Gerow, K. G., Huber, H. F., & Nathanielsz, P. W. (2019). Effect of maternal obesity on fetal and postnatal baboon ( Papio species) early life phenotype. Journal of Medical Primatology, 48(2), 90-98. https://doi.org/10.1111/jmp.12396.
11. Martin, C., Ling, P.-R., & Blackburn, G. (2016). Review of infant feeding: Key features of breast milk and infant formula. Nutrients, 8(5), 279. https://doi.org/10.3390/nu8050279.
12. Power, M. L., & Schulkin, J. (2013). Maternal regulation of offspring development in mammals is an ancient adaptation tied to lactation. Applied & Translational Genomics, 2, 55-63. https://doi.org/10.1016/j.atg.2013.06.001.
13. Ruiz, L., Espinosa-Martos, I., García-Carral, C., Manzano, S., McGuire, M. K., Meehan, C. L., McGuire, M. A., Williams, J. E., Foster, J., Sellen, D. W., Kamau-Mbuthia, E. W., Kamundia, E. W., Mbugua, S., Moore, S. E., Kvist, L. J., Otoo, G. E., Lackey, K. A., Flores, K., Pareja, R. G., … Rodríguez, J. M. (2017). What’s normal? Immune profiling of human milk from healthy women living in different geographical and socioeconomic settings. Frontiers in Immunology, 8, 696. https://doi.org/10.3389/fimmu.2017.00696.
14. Sinclair, K. D., Rutherford, K. M. D., Wallace, J. M., Brameld, J. M., Stöger, R., Alberio, R., Sweetman, D., Gardner, D. S., Perry, V. E. A., Adam, C. L., Ashworth, C. J., Robinson, J. E., & Dwyer, C. M. (2016). Epigenetics and developmental programming of welfare and production traits in farm animals. Reproduction, Fertility and Development, 28(10), 1443. https://doi.org/10.1071/RD16102.
15. Victora, C. G., Bahl, R., Barros, A. J. D., França, G. V. A., Horton, S., Krasevec, J., Murch, S., Sankar, M. J., Walker, N., & Rollins, N. C. (2016). Breastfeeding in the 21st century: Epidemiology, mechanisms, and lifelong effect. The Lancet, 387(10017), 475-490. https://doi.org/10.1016/S0140-6736(15)01024-7.
16. Wu, X., Jackson, R. T., Khan, S. A., Ahuja, J., & Pehrsson, P. R. (2018). Human milk nutrient composition in the united states: Current knowledge, challenges, and research needs. Current Developments in Nutrition, 2(7). https://doi.org/10.1093/cdn/nzy025.
17. Zambrano, E., & Nathanielsz, P. W. (2013). Mechanisms by which maternal obesity programs offspring for obesity: Evidence from animal studies. Nutrition Reviews, 71, 42-54. https://doi.org/10.1111/nure.12068.