The cayo santiago primate colony

This is an account of the vicissitudes of the monkeys on Cayo Santiago. In it is described the relationship of the establishment of that primate colony to the development of the National Regional Primate Research Center Program in the United States and the Laboratory of Perinatal Physiology in Puerto Rico. The Cayo Santiago colony opened new aspects of biomedical research and stimulated the general use of nonhuman primates in behavioral as well as physiological investigations.     

Juvocimenes: potent juvenile hormone mimics from sweet basil

Two compounds with highly potent juvenile hormone activity were isolated and identified from the oil of sweet basil, Ocimum basilicum L., Labiatae.     

Cellular changes in the granulosa layer of the maturing ovarian follicle of the domestic fowl

1. The relationships between length, width and height of the maturing ovarian follicle of the domestic fowl (Gallus domesticus) are shown.

2. During the rapid‐growth phase (yolk deposition) of the oocyte, i.e. an increase in size from about 9 mm diameter to 35 mm diameter, there is about a 15‐fold increase in its surface area. During this time the number of granulosa cells adjacent to the oocyte increases by about 5‐fold.

3. The granulosa cells become flatter during the growth period of the follicle, consequently increasing their surface area adjacent to the oocyte by about 3‐fold.

4. Together the change in shape of the granulosa cells and the increase in their number account for the increase in area of the granulosa layer during follicular growth.

5. Measurement of the DNA content of the granulosa layer indicated a progressive decrease in the cellular content of DNA as the follicle matures.     

The nitrogen‐sparing effect of methionine in chicks receiving a protein‐free diet supplemented with arginine: Effect of various methionine substituents

1. The nitrogen‐sparing effect of methionine in chicks fed on a protein‐free diet containing arginine was examined in three 10‐d trials. Chicks received either a protein‐free diet, this diet supplemented with arginine and methionine or diets containing arginine in which the methionine was replaced by various methionine‐related compounds.

2. Body‐weight changes, nitrogen retentions and uric acid‐nitrogen excretion indicated that the methyl moiety was unlikely to contribute to nitrogen sparing activity and that cysteine, or possibly glutathione, played an important role. The possible mechanism of the nitrogen‐sparing effect is discussed.     

A simple caliper technique for the estimation of abdominal fat in live broilers

1. A caliper technique for estimating the amount of abdominal fat in live broilers is described.

2. Sixty‐three male and 47 female broilers sampled at 63 d of age from an unselected control line were used to examine the accuracy of the caliper measure in predicting abdominal fat.

3. Phenotypic correlations between caliper measure and the proportion of abdominal fat were + 0.80, +0.79 and +0.81 in males, females and the heaviest 20% of males respectively.

4. The application of the technique as an indirect means of selecting for decreased abdominal fat in commercial broiler breeding programmes is discussed.     

Attempts to eliminate from field beans the anti‐nutritive factor which reduces egg production

1. In a series of experiments with laying hens, attempts were made to eliminate the anti‐nutritive factor which reduces egg production when feeding field beans (Vicia faba L.) as a source of supplementary protein in cereal‐based diets.

2. Neither pelleting diets nor heat processing the beans by autoclaving proved beneficial. A continuous‐flow process for infra‐red heating of the seeds at 150 °C for 70 s followed immediately by flaking (micronisation) gave inconsistent results.

3. Beans having a white skin with associated low tannin content, did not support significantly higher egg production than did a normal brown‐skinned bean, thus indicating that tannin was not the main anti‐nutritive factor.

4. A cotyledon fraction, obtained by mechanical removal of the tannin‐containing skin from brown beans, did not support higher egg production than did the whole bean, and the corresponding brown‐skin fraction did not reduce egg production when substituted for cereal in the control diet. Again this indicated that tannin was not implicated.     

Apparent independence of glucose tolerance and body fat content in 8‐week‐old broilers

1. A possible relationship between glucose tolerance and body‐fat content was examined in broilers selected at 2 and 4 weeks of age for fast or slow glucose disposal.

2. At 8 weeks of age, selected chickens were different in glucose tolerance but similar in body weight, food conversion efficiency, carcass composition and glucose‐induced insulin release.

3. Therefore, variations in glucose regulation and insulin sensitivity which are detectable at an early age, do not appear to be related to body composition in 8‐week‐old broilers.