Winter 2010

Since 1967, Royal Canin has been at the forefront of developing innovative nutritional responses in the field of dog breeding. Even if nutrition is fundamental in breeding, it cannot give all the keys for success. Application of reproduction techniques is the deciding factor.

Breeder's Handbook
Feeding Between Breedings:
Rebuilding the Dam's Essential Body Reserves

By Bretaigne Jones, DVM
Royal Canin, USA, Inc.

Most owners recognize the need for optimal nutrition for the female during pregnancy and lactation. However, little notice is taken of the period between the completed weaning of one litter and the first signs of the next estrous cycle. During this interval, it is imperative for dogs that will be rebred at the next estrous cycle to receive the appropriate food, both in energy density and nutrient quality. Lower quality food can lead to breeding issues such as failure to settle, smaller litters, and higher incidences of pregnancy toxemia and eclampsia.

St. BernardThe concept of “eating for two” is widely recognized in association with pregnancy. Typically this phrase refers to necessary nutrition for the mother and the babies, but the nutritional needs during pregnancy go well beyond just the maintenance needs of the dam and the developmental needs of the fetuses. In addition to those needs are the generation of uterine tissue, miles of blood vessels, placental tissue, and development of mammary tissue.

Regardless of the stage of reproduction, the breeding bitch will deferentially provide nutrients to the babies through the placenta or through milk, regardless of her own needs. Consequently, she is drawing upon her own body reserves for necessary minerals, proteins, fats, and vitamins to meet the needs of her offspring. This is why a lactating bitch is often haggard looking. It is this depletion of body stores that necessitates a higher level of nutrition between breedings in order to restore those nutrient reserves.

At the end of the first six weeks of pregnancy, there is only a 10% increase in energy needs. However, by the end of pregnancy, the average bitch has increased her energy needs to 140% to 150% of maintenance. And during peak lactation, the third and fourth week depending on number of pups and breed, the bitch may demand 300% of her maintenance energy levels, with necessary elevations in most nutrients. During late pregnancy, throughout lactation, and through the recovery interim between breedings, differing levels of increased energy and nutrient content are critical to the health and well-being of the mother and pups.

Estrous Interval Energy and Nutrient Requirements
The interval between weaning and the next estrus can be confusing nutritionally. While the bitch is back at maintenance energy needs, she needs higher levels of certain nutrients than are recognized for maintenance health. Calcium and phosphorous are good examples. According to the National Research Council (NRC) 2006 edition of Nutrient Requirements of Dogs and Cats, the minimum calcium requirement for adult dog maintenance is 0.50 grams of calcium per 1,000 Kcal metabolizable energy (ME). The recommended level is reported at 1.0 grams per 1,000 Kcal ME for calcium and 0.75 g/1,000 Kcal ME for phosphorous.

Compared to the recommended levels for late gestation (last four weeks of pregnancy), and peak lactation (weeks 3 and 4), the recommended allowance for calcium is 1.9 grams per 1,000 Kcal and phosphorous is 1.2 grams per 1,000 Kcal. These levels are 190% and 160%, respectively, of the normal maintenance levels. If the bitch carried an average size litter and successfully nursed to complete weaning at 6 weeks after whelping, she not only utilized every gram of the nutrients provided in the diet, but also drew on her own body reserves in her bones to some extent. In the case of a larger litter, her body reserve resources provide even more to meet the needs of the growing pups during late pregnancy and throughout lactation.

Replenish the Deficit to Improve Performance
When the bitch has totally weaned her pups, she’s technically back to maintenance energy needs. However, her body is still repairing from the pregnancy and delivery, and her mammary tissue is returning to a normal non-reproductive state. The deficits created by providing all the nutritional needs of the developing and growing pups for months need to be corrected. The owner cannot depend on the visual appearance of the bitch’s body condition score to reliably assess her nutritional needs. She may look good externally, but still have deficient nutrient reserves.

Other nutrients that typically need to be restored include omega-3 and omega-6 fatty acids, zinc, copper, manganese, taurine, arginine, and tyrosine.

If a bitch is going to be bred on her next estrous cycle, it is imperative that she be provided the optimal diet after weaning to rebuild her body stores. The drain on her reserves will compound with each pregnancy. So with pregnancy number two, there may not be an appreciable difference in her reproductive performance, but with pregnancy three and four there will be decreases in litter size, viable puppies, milk production, and her “resting” body condition score. There is definitely an additive effect with successive pregnancies and lactations to the detriment of the bitch's base reserves, and to her health.

A vitally important component of lactation is the production of colostrum, rich in maternal antibodies, to provide immune protection for the newborns. The wear and tear on the bitch bred repeatedly with inadequate nutrition between litters will result in a compromised immune system, contributing lower levels of antibodies in the colostrum resulting in unprotected puppies. So not only are litters smaller and the puppies less vigorous, they are much more vulnerable to viruses, bacteria and parasites.

Nutrients x Lifestage
Minimum Maintenance amounts
Recommended Maintenance amounts
Recommanded gestation/lactation amounts
Protein grams/1,000 Kcal ME
Total fat grams/ 1,000 Kcal ME
10 (adequate)
Linoleic acid grams/ 1,000 Kcal ME
2.4 (adequate)
Alpha-linolenic acid grams/ 1,000 Kcal ME
0.09 (adequate)
EPA/DHA grams/ 1,000 Kcal ME
0.11 (adequte)
Calcium grams/ 1,000 Kcal ME
NRC 2006 Nutrient Requirements of Dogs and Cats - Canine values

Assessing the Needs of the Resting Dam
Nutrients expressed in amounts per 1,000 Kcal metabolizable energy are not generally provided on product packaging or in brochures. This manner of expression allows the direct comparison between diets for specific nutrients, as well as a very accurate reflection of nutrient quantity when fed to a specific dog. If a German Shepherd bitch needs 2,100 Kcal ME for maintenance, a diet that provides 1 gram of calcium per 1,000 Kcal then provides 2.1 grams calcium in a normal day’s food intake. Likewise, a 10-pound Dachshund bitch requires 400 Kcal ME for maintenance. If a diet provides 1 gram calcium per 1,000 Kcal ME, the Dachshund will take in 0.4 grams calcium in her food for that day. A call to the pet food manufacturer’s technical service center should provide these details. If they don't know, they haven’t done their homework.

An owner that does not intend to rebreed on a successive heat cycle provides more time for the bitch to rebuild her body reserves. Every pregnancy and lactation places a substantial strain on the momma dog. Whether it is to be her only pregnancy or not, recovery to normal takes months, physically as well as nutritionally.

© 2010 ROYAL CANIN USA, Inc.

Photos courtesty Royal Canin. References available upon request.

Ronald N. Rella, Director, Breeder Services
Customer Service | Phone: 919-233-9767 | Email:

© The American Kennel Club 2010