Page 392 - Small Animal Clinical Nutrition 5th Edition

402 Small Animal Clinical Nutrition

edly have a greater incidence of dystocia (Lawler and Monti,
VetBooks.ir 1984). Historical or physical evidence of a narrow pelvic canal,
whether due to trauma, genetics or nutritional deficiency war-
rants careful assessment. Mammary tissue and teat develop-
ment should be evaluated. Although congenital defects (e.g.,
multiple teats or teat malformation) rarely prevent queens from
raising normal-sized litters, genetic selection away from such
traits is advisable. Only cats in excellent health should be con-
sidered for breeding.
Tomcats should also be healthy and in optimal body condi-
tion (BCS 3/5); however, decreased reproductive performance
associated with moderate deviations from ideal (BCS <2/5 to
>4/5) have not been reported. In addition to a standard physi-
cal examination, the penis, prepuce and testes should be evalu-
ated for anatomic defects. Previous reproductive performance
including a weight history should be reviewed. The level of
Figure 22-1. Body weight and energy intake during gestation and activity required during the breeding period should be ascer-
lactation in queens. Unlike bitches, which have a dramatic increase
in energy intake and body weight during the last trimester, queens tained. Single matings result in minimal changes in energy
have a regular linear increase in both body weight and energy intake needs, whereas multiple matings may require an increase in the
throughout gestation. Mobilized stores of body fat provide needed amount of food provided, based on body condition.
energy during lactation, which accounts for weight loss during this
period. Food intake parallels lactation and peaks during the sixth to Pregnancy
seventh week. (Adapted from Loveridge GG. Body weight changes
and energy intake of cats during gestation and lactation. Animal The first assessment step is to diagnose pregnancy. Abdominal
Technology 1985; 37: 7-15.) palpation is used most commonly to diagnose pregnancy in
cats. The fetal vesicles can be reliably palpated from 14 to 25
days of gestation (Feldman and Nelson, 1996). An enlarged
PATIENT ASSESSMENT uterus is palpable from Day 25 to parturition. Ultrasound can
detect pregnancy by Day 11 of gestation and fetal heartbeats are
Estrus and Mating typically heard at 22 days (Davidson et al, 1986). Radiographic
Optimal nutrition for reproducing cats should precede mating diagnosis requires calcification of the fetal skeleton and is most
and conception, and ideally start when the animal is a kitten. reliable after Day 45 of gestation. Gestation usually lasts 63 to
Female cats are seasonally polyestrous. Repeated estrous cycles 65 days (range 58 to 70 days) in queens, thus radiography is not
occur throughout the breeding season, which typically occur useful for early pregnancy diagnosis, but is useful for determin-
from January through September in the northern hemisphere. ing litter size. In addition to the diagnosis of pregnancy, an
Light duration and intensity are major determinants for the assessment should include a dietary history, physical examina-
estrous period. Therefore, artificial lighting and latitude varia- tion and any indicated laboratory analyses. Evaluations of body
tion alter the breeding period for individual cats. Vocalizing, condition, weight gain and food intake are most important.
rolling, rubbing and treading characterize estrus in the queen; Minimal diagnostics are usually required if the pelvic structures
these behaviors culminate in acceptance of the male. Behavioral and mammary glands were evaluated and parasite, feline
estrus averages seven to nine days (range one to 21). Cats are leukemia virus/feline immunodeficiency virus and vaccination
induced ovulators (i.e., coital contact is typically required for a status were determined before breeding.
luteinizing hormone surge and ovulation). One of the early indicators of successful breeding and con-
Queens should have a current vaccination history and be ception is a steady gain in body weight. Weight gain increases
treated for internal and external parasites before breeding. A linearly from conception to parturition in queens (Figure 22-
history and physical examination should precede breeding to 1). This pattern is different from that of most other species,
assess problems that may interfere with conception, parturition which experience small increases in body weight until the last
and lactation. Queens should be at ideal body weight at mating third of gestation when weight gain and energy intake greatly
(body condition score [BCS] 3/5). Small variations in body increase. Weight gain in early pregnancy is not associated with
condition can be corrected during pregnancy; however,cats that significant growth of reproductive tissues or conceptuses but
are significantly under- or overweight (BCS <2/5 or >4/5) appears to be stored in energy depots (presumably as fat) to
should not be bred. Both obesity and undernourishment can be support lactation (Loveridge and Rivers, 1989). Mean weight
detrimental to reproductive performance. Malnourished gain during gestation is approximately 40% of the pre-mating
queens may fail to conceive, abort or bear small, underweight weight (900 to 1,200 g for a litter of average size) and has been
kittens and have a markedly reduced lactation. Lactating described by the equation (Loveridge and Rivers, 1989):
queens normally lose weight, but their body weight should Weight gain (g) = 888.9 + (106.5)n (where n = number of
return to normal before the next breeding. Obese cats report- neonates).