Ming, the mouse is pregnant! What should I do? How can I be a qualified "caretaker"?

 

Let's start with gestation and lactation care.

 

Gestation and Lactation Care

Gestation Period

A mouse's gestation period is typically 19-21 days. Provide a suitable environment and proper nutritional support for the pregnant female.

● Temperature and Humidity: Maintain ambient temperature at 20-26°C and relative humidity at 40-70%, avoiding extremes of heat or cold.

● Bedding Selection: Provide soft, warm bedding such as cotton or wood shavings to ensure the female can nest comfortably.

 

● Minimize Disturbance: Place cages in a quiet, dimly lit area, avoiding frequent interference and noise.

● Vitamin E: Add vitamin E-rich foods, such as sunflower seeds, to support healthy fetal development.

● Adequate Water: Ensure the female has access to clean, fresh water at all times.

● Note on Maternal Issues: If the female has a history of cannibalism, it is advisable to avoid single housing. Housing two females together can reduce stress-related behaviors.

Note on Cannibalism: Cannibalism can be caused by various factors, including poor maternal instinct (strain-dependent), poor fetal development, accidental ingestion during birth, or maternal fright from noise stimulation during parturition. Therefore, minimize noise and avoid disturbing the female during and immediately after parturition.

Lactation Period

The mouse lactation period is 20-22 days. Separation can occur at the end of lactation. It is recommended to cull negative pups or those not needed for the study early, as this is more beneficial for the survival and development of the positive pups.

Soon after birth, observing a white spot ("milk spot") on the left side of the pup's abdomen through the translucent skin indicates good health.

Consider Cross-fostering in the following situations: Maternal fright; poor pup development; maternal cannibalism.

Cross-fostering Measures:

1.  Select a Foster Mother: Choose a female with good maternal instincts and a different coat color. Her gestational age should be 1-3 days greater than that of the original mother.

2.  Remove Original Scent: Rub the pups with bedding from the foster mother's cage to remove the original mother's scent, then place the pups into the foster mother's cage.
 

Common Health Issues
 

1. Alopecia (Hair Loss)
 

Causes of alopecia in mice can include grooming, infection, or environmental factors.

1) Grooming-Induced Alopecia: Alopecia in newborn pups is often caused by grooming by the mother or cagemates.

○ Presentation: The hairless area typically has clear borders without obvious skin lesions. This often occurs on the whiskers, back, around the eyes, and ears.

○ Management: If the alopecic area shows no other abnormalities (redness, exudate, etc.), no specific treatment is usually required.
 

 

2) Disease or Parasite-Induced Alopecia: Certain diseases or parasitic infections (e.g., fungal skin infection, mite infestation) can also cause alopecia.

○ Presentation: The alopecic area may be accompanied by skin lesions like redness, exudate, or crusting.

○ Management: If a disease is suspected, consult a veterinarian promptly for diagnosis and treatment. Common treatments include antifungal or antiparasitic medications.

3) Environment-Induced Alopecia: Poor environmental conditions can also lead to alopecia.

○ Management: Ensure the housing environment meets the physiological needs of mice (20-26°C, 40-70% humidity). Clean cages regularly and avoid using irritating chemicals.
 

2. Fighting Issues

Mice, especially males, may fight.

● Management: To prevent injury from fighting, consider single housing, reducing stocking density, or adding more nesting material. House a maximum of 5 mice per cage, with 3 per cage being preferable when possible.

 

References:

[1] Peng Xu, Yin Hailin. Breeding strategies for genetically engineered mice. Experimental Science and Technology, 2021, 19(05), 31-37.

[2] Central South University Laboratory Animal Center.

Special Statement: This article is from the official WeChat account of MingCeler Biotech. Personal sharing is welcome. Media or institutions are prohibited from reprinting to other platforms without authorization. For reprint permission or other inquiries, please contact us via the official account backend or at sales@mingceler.com.

Disclaimer: Some materials are sourced from the internet. Contact us for removal if infringement is found. This article is for informational purposes only. The views expressed do not represent the official stance of MingCeler Biotech.