Although miniature cows are smaller, their miniature cow pregnancy period is remarkably the same as that of a normal-sized cow. Knowing about gestation can be very useful if you are a cow owner or are planning to breed one, in order to be able to expect a healthy calf.
Miniature cows will normally have a gestational period that lasts for about 9 months, which means that it is usually between 279 and 292 days. The average is 283 days, but it may differ due to different genetics and breeds.
Although miniature cattle have a smaller body size, they reproduce in a manner similar to large cattle.
Typically, the heifer’s mature reproductive status, age, and size are sufficient to breed a healthy heifer. Typically, cows are bred for the first time at about 14 to 15 months, producing their first calf at two years of age.

But breeding should be based on ‘The Individual’ and not age alone. A heifer can be physically matured through a veterinary examination or by a knowledgeable cattle breeder.
Pregnancy signs can be subtle at first, making early detection challenging. Some changes owners may notice include:
Signs may be other than pregnancy and should not be relied upon as evidence of pregnancy.
When the pregnancy is in its late stages, it is really important to prepare. Always ensure that the cow has a clean water source, good nutrition, protection from the elements, and a clean, comfortable place to give birth.
There’s also a vet who can give you advice about feeding, keeping an eye on your cow’s health, vaccinations, and what you can expect during delivery.
The size of newborn miniature calves will depend on the breed and genetics of the calf and is typically in the range of 40-60 lbs.
Postpartum observation for both the cow and her calf is essential. The calf must suckle adequately, while the cow must be examined for any complications.

In case of an unusual labor or any distress on the part of the cow, the services of a veterinarian must be sought immediately.
Not all miniature cows have to be bred. Adoption is a great way of finding a miniature cow a good home.
Think about what it will take in terms of space, shelter, food, health care, and general maintenance before you adopt. These docile creatures require dedication, not just love.
At times, the greatest way of showing your love for miniature cows is by adopting one.
References Link: https://www.researchgate.net/publication/331894209_Features_and_status_of_miniature_indigenous_germplasm_of_cattle-Malnad_Gidda