Page 295 - Small Animal Clinical Nutrition 5th Edition

300 Small Animal Clinical Nutrition

VetBooks.ir Box 16-3. Body Weight Gain in Puppies.

Birth weight of puppies is the single most important measure of parturition and it may triple by the third week. Although the relative
their chances of survival, and reflects, among other factors, the weight gain gradually decreases, weight gain in g/day varies little
adequacy of the bitch’s nutrition during pregnancy. The evolution of from the second to the fourth week of life.
a puppy’s body weight gives useful information about food intake Daily gain can vary markedly. Although puppies should be
and general health. Body weight should be recorded within 24 weighed every day or every other day, a more precise evaluation
hours after parturition, and then daily or every other day for the first should be based on the average weekly weight gain.
four weeks of life, using an accurate gram scale. Between one and two months of age, daily weight gain may aver-
age 3 g/kg adult body weight, and between 2 and 4 g/kg adult body
BIRTH WEIGHT weight through weaning. These numbers may be used to help
Due to variation in breed size, an exact optimal birth weight is diffi- assess growth rates. However, dogs do not grow linearly; the
cult to estimate for individual puppies. Body weight at birth corre- growth curve has a sigmoid shape, with a fast exponential growth
lates primarily with the weight of the mother; birth weights range component first followed by slower growth. The exact timing of
from 1% for some large and giant breeds to about 6.5% in these phases differs from breed to breed. As a rule, small- and
Chihuahuas. Interestingly, investigators found a consistent ratio medium-sized dogs (up to 25 kg) reach about 50% of their adult
between the weight of the total litter and the body weight of the weight around four months of age, whereas dogs with adult weights
dam. Birth weight of the entire litter averages about 12 to 14% of above 25 kg reach the 50% point at about five months of age.
adult body weight. The ratio can be slightly smaller in large breeds.
Given the number of puppies and the ratio of litter to adult body Table 1. Average daily weight gain of puppies.*
weight, the birth weight of individual puppies can be evaluated in Week % of current body weight
relation to the expected total number of puppies per litter. 1 2 8 (5-10)
6
3 4
BODY WEIGHT GAIN 4 3.5
Daily weight gain averages about 5% of the puppy’s current body
weight during the first four weeks after parturition. The absolute *Adapted from Kienzle E, Meyer H, Dammers C, et al.
Milchaufnahme, Gewichtentwicklung, Milchverdaulichkeit, sowie
daily weight gain is lowest during the first week of life; however, the Energie- und Nährstoffretention bei Saugwelpen. Fortschritte in der
relative increase is largest (average 7.7% of body weight), and can Tierphysiologie und Tierernährung (Advances in Animal Physiology
reach 10% of body weight (Table 1). In the first 48 hours, the and Animal Nutrition) 1985; Suppl. No. 16: 27-50. Mundt H-C,
increase in body weight is not related to the puppy’s body weight, Thomée A, Meyer H. Zur Energieund Eiweißversorgung von Saug-
because healthy smaller puppies eat relatively more in an effort to welpen über die Muttermilch. Kleintierpraxis 1981; 26: 353-360.
replete body reserves. The Bibliography for Box 16-3 can be found at
The puppy’s body weight often doubles by eight to 10 days after www.markmorris.org.

life. However, expressed per kg body weight, puppies’ milk better not to over feed orphaned puppies to avoid diarrhea.
intake is highest during the first week and decreases progres- Table 16-5 summarizes the estimated energy requirements of
sively (Kienzle et al, 1985). Puppies born with a lower body orphans to transition them to milk replacers. The initial
weight ingest an amount of milk similar to that of their larger amounts in Table 16-5 are lower than the amounts discussed
littermates during the first 48 hours of life (Oftedal, 1984; above. These lower levels are intended to help orphaned pup-
Kienzle et al, 1985). pies adapt to orphan formulas. When using commercial milk
The energy requirement of a puppy is the sum of energy replacers, it is usually best to follow the label recommendations.
needed for maintenance and the requirement for growth.
Because puppies sleep more than 80% of the time, and huddle Protein
together in a warm whelping box, they are able to decrease their Protein digestibility of bitch’s milk is very high (up to 99%), and
energy requirements for maintenance to a level that approach- nitrogen retention is about 90% during the first week (Mundt
es resting energy requirement (70 kcal/BWkg ) (Mundt et al, et al, 1981). Compared with cow’s milk, bitch’s milk contains
0.75
1981) during the first week of life. Therefore, all additional more than twice as much protein per 100 ml (7.5 vs. 3.3%)
ingested energy can be used for growth. Their energy intake (Table 15-3). Bitch’s milk also provides high levels of arginine,
averages about 240 kcal (1 MJ)/kg body weight/day during the lysine and branched-chain amino acids (Meyer et al, 1985a;
first four weeks of life.Averages,however,may vary from as high Swaisgood, 1995). This nutrient profile is important when
as 287 kcal GE (1.2 MJ)/kg body weight during the first week assessing and formulating milk replacers, and reflects the enor-
of life to as low as 190 kcal GE (0.8 MJ)/kg body weight by mous anabolic activity of puppies at this young age. Protein
Week 4 (Oftedal, 1984; Mundt et al, 1981; Kienzle et al, 1985). requirements should be met if puppies ingest adequate amounts
This information can also be generally applied to orphaned of energy as that contained in bitch’s milk.
puppies. A very common mistake is to underestimate the ener- Commercial milk and homemade replacer formulas should
gy requirements of neonates. In the beginning, however, it is have adequate protein and essential amino acid content and