Gamallo A, Trancho G J, Alario P
Department Fisiologia Animal, Facultad de Biologia, Universidad Complutense de Madrid, Spain.
Physiol Behav. 1988;44(3):307-11. doi: 10.1016/0031-9384(88)90030-3.
Two experimental methods to provoke caloric restriction during suckling were used. Each of the methods utilized two different rat groups: Low Growth (LG) and High Growth (HG). In one method, the groups also differed in a social factor, litter size: crowded (Cr) and control (Co). Growth differences and high levels of social competition were found among pups of the crowded group with Low Growth (CrLG) compared to the group with High Growth and small litters (CoHG). Both methods resulted in growth differences between respective groups from the first week of suckling. Differences in animal groups persisted forty days after weaning. LG animals had higher defecation scores with lower activity in the open-field test, higher susceptibility to restraint ulcers and adrenal hypertrophy than HG rats, in litters of equal size. However, early stimulation from social competition among pups in larger different litters in CrLG group counteracted nutritional factor effects. Elevated open-field defecation and ulceration scores with adrenal hypertrophy were found in CoHG rats.
采用了两种在哺乳期间引发热量限制的实验方法。每种方法都使用了两组不同的大鼠：低生长组（LG）和高生长组（HG）。在一种方法中，两组在一个社会因素——窝仔数上也存在差异：拥挤组（Cr）和对照组（Co）。与高生长且窝仔数少的组（CoHG）相比，拥挤的低生长组（CrLG）的幼崽之间存在生长差异和高水平的社会竞争。两种方法在哺乳第一周就导致了各对应组之间的生长差异。断奶后四十天，动物组间的差异依然存在。在等大窝仔中，LG组动物在旷场试验中的排便分数更高、活动更少，对束缚性溃疡的易感性更高且肾上腺肥大，比HG大鼠更明显。然而，CrLG组中不同大小窝仔的幼崽之间社会竞争产生的早期刺激抵消了营养因素的影响。CoHG大鼠出现了旷场排便分数升高、溃疡分数升高以及肾上腺肥大的情况。
