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

Year 2025,

Canberk Yılmaz , Defne Engür , Pembe Keskinoğlu , Abdullah Kumral , Osman Yılmaz

https://doi.org/10.62425/jlasp.1441481

Abstract

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.

Keywords

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

Ethical Statement

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.

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

Abstract

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.

Keywords

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

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