Severe undernutrition in growing and adult animals

Neonatal undernutrition and self-grooming development in the rat: long-term effects

The effect of neonatal undernutrition on six different self-grooming components was examined in male rats during the pre- and postweaning periods. Rats underfed by the maternal nipple-ligation procedure before weaning did not exhibit significant score differences in the various self-grooming measurements. In contrast, after weaning they showed a significant increment in the duration of face-washing, head-washing, fur licking and body-scratching. In all cases, the total postweaning self-grooming activity was significantly increased in the formerly underfed rats. Present data suggest that neonatal undernutrition may presumably interfere with the sequential maturational processes of central and/or peripheral mechanisms underlying some components of self-grooming behavior.

A differential effect of protein and calorie deficiency on ovarian follicular growth in the sow

Either protein or calorie deficiency alters the pre-antral growth of ovarian follicles in the sow. Protein deficiency depressed the rates of oocyte, oocyte nuclear and oocyte nucleolar growth in follicles composed of one or more layers of granulosa cells. Calorie deficiency depressed the growth of the follicle envelope but only in multilaminar follicles. It is concluded that the effect of protein deficiency on ovarian follicular growth differs significantly from that of calorie deficiency in this species. Neither treatment altered the maximum dimensions of the oocyte at the completion of the intra-ovarian growth phase (phase A).

Severe undernutrition in growing and adult animals. 19. The metabolic rates and body temperature of calorie-deficient and protein-deficient pigs

1. The body temperatures and resting oxygen consumptions of calorie-deficient and protein-deficient pigs have been measured at 12, 21, 26, 30, 36 and 40°.

2. A fall in the environmental temperature was followed by a rise of the same order in the oxygen consumptions of the two groups of animals, and past and present evidence indicates that the rise in normal animals of the same size is similar.

3. The rectal temperatures and oxygen consumptions of the protein-deficient pigs were higher at all the above temperatures than those of the calorie-deficient animals but not as high as those of normal animals.

4. The differences in rectal temperatures and oxygen consumptions were highly significant at 30°, which is probably within or near the zone of thermal neutrality of all the animals.

Severe undernutrition in growing and adult animals. 17. The ultimate results of rehabilitation: pigs

1. Ten pigs which had been undernourished for a year, and weighed about 5.5 kg at that time, were rehabilitated on an excellent dict. They grew fast, but no faster per kg body-weight than normal pigs, and they stopped growing at the same chronological age. Consequently, they did not attain the same adult size as the normally reared pigs.

2. The rehabilitated animals appeared to be fatter than the control animals, but the proportions of muscle to bone in the carcasses of the males and females were within the range to be expected in normal animals of the same fat-free weight, although the castrates may have been somewhat less muscular on this basis.

3. The weights of the organs per kg of fat-free body weight were within the limits found in normally reared animals of the same fat-free weight.

The effect of normal development and of severe undernutrition on some minor components of cortical bone

1. The amounts of calcium, magnesium, sodium and citric acid in the bones of undernourished pigs 1 year old were compared with the amounts in the bones of smaller newborn animals, normal animals of the same weight aged 4 weeks and of the same age weighing 170kg. 2. The differences that were found between 4 weeks and 1 year of age in the normal animals were expected as effects of aging. However, between birth and 4 weeks of age the changes in composition were in the opposite direction to those between 4 weeks and 1 year. 3. Undernutrition produced a bone that resembled chemically that of an animal 1 year old.

The effect of normal development and of undernutrition on the exchange of[32P]orthophosphate with bone powder in vitro

1. The effect of age and undernutrition on the exchange of phosphate in the cortical bone powder of pigs with [(32)P]orthophosphate was investigated in vitro. 2. The extent of exchange fell steadily from birth to old age. 3. The bones of animals undernourished for 1 year behaved like those of animals 3(1/2) years old.

Artificial Feeding of Neonatal Rats

Newborn rats, fed either cow's milk or rat's milk by tube, developed a "bloat" and the time required for emptying the stomach increased. When these animals were allowed to suckle on nonlactating foster mothers, no evidence of this syndrome was observed. Based on these observations, a technique was developed for the artificial feeding of newborn rats. When the diet was rat's milk, growth equivalent to that of animals fed solely by lactating females was obtained. A diet of cow's milk did not support adequate growth.