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Biomedical subjects

H Zucker

Publications and source records attributed to H Zucker.

At least 55 records · Page 3Linked to original sources

Effects of fibre on digestibility and passage time in callithricidae.

The effects of fibre in a pelleted diet on food intake, digestibility of crude fibre, dry matter and energy, on passage time and consistency of faeces were studied in 2 species of Callithricidae, Callithrix jacchus and Saguinus fuscicollis. Coarse cellulose, microcellulose, wheat bran and shrimp meal (chitin = crude fibre) were tested in diets containing 2,4 and 6% total crude fibre, respectively. Digestibility and passage time were determined by inclusion of 0.5% Cr2O3 in the diet. Both celluloses had little influence on the digestibility of energy and dry matter. Digestibility of crude fibre was very low. Wheat bran led to evident depression of energy and dry matter digestibility. High digestibility of crude fibre occurred at the higher levels of inclusion in the diet. Shrimp meal was highly digested with little influence on digestibility of energy and dry matter, indicating considerable degradation of chitin. Wheat bran showed a marked effect, while microcellulose had no effect on passage time, consistency and volume of faeces.

Animal Feed↗

Biological activity of 1 alpha,25-dihydroxyergocalciferol in rachitic chicks and in rats.

The bioactivity of chemically synthesized 1 alpha,25-dihydroxyergocalciferol (1,25(OH)2D2) was investigated in rachitic chicks and in vitamin D-deficient rats. In prophylactic and in curative chick assays 1,25(OH)2D2 is about 10 times less active than 1 alpha,25-dihydroxycholecalciferol (1,25(OH)2D3). Since in the same bioassay vitamin D2 is more than 80 times less active than vitamin D3, discrimination against vitamin D2 in chickens must occur at two points, before and after the formation of 1,25(OH)2D2. Receptor binding studies revealed that the chick duodenal receptor binds 1,25(OH)2D2 with the same capacity as 1,25(OH)2D3. In rats 1,25(OH)2D2 proved to have the same antirachitic activity as 1,25(OH)2D3 and might become of therapeutic interest for application in man and domestic animals if the expectations of lower toxicity are confirmed.

Animals↗

Biological activity of glycosides of vitamin D3 and 1 alpha-hydroxyvitamin D3.

For the first time, the biological activity of the newly synthesized glycosides of vitamin D3 and of 1 alpha(OH)D3 has been studied in rats, chickens, and Japanese quails. Glucosidation did not reduce the activity of vitamin D3. In chickens, vitamin D3 glucoside has an activity of 90% to 95% as compared to the aglycon. In rats vitamin D3 glucoside is equally active when given by intravenous or oral route. Glycosides of 1 alpha (OH)D3, however, show a lower activity in rats, chickens, and quails. 1 alpha (OH)D3 glucoside has about 10% activity of the free 1 alpha (OH)D3, while 1 alpha (OH)D3 cellobioside is without any activity in chickens. 1 alpha (OH)D3 glucoside might be of interest, due to its broader therapeutical dosage range.

Administration, Oral↗

Evaluation of a pelleted diet in a colony of marmosets and tamarins.

By offering various pelleted diet modifications to five species of Callitrichidae, a palatable 24% protein diet was developed. The animals received limited fruit supplement, and families received an additional meal of commercial baby food. The pellets supplied approximately 75% of dietary energy and 95% of total protein. In 15 months on this regimen, mortality dropped drastically and fertility improved. No signs of a nutritional deficiency were observed. It was concluded that the nutrient levels of this diet were adequate or above actual requirements.

Animal Feed↗

Calcinogenic activity of vitamin D3 and vitamin D3 palmitate in rat and rabbit.

Experimental hypervitaminosis D was produced in rabbits by feeding 25,000 I.U. vitamin D3 or the corresponding amount of vitamin D3 palmitate per kg of diet. Hypercalcemia and hyperphosphatemia was accompanied by increased CaBP activity and reduced weight gain in the vitamin D3 group as well as in the vitamin D3 ester group. The degree of calcification in the aorta and in the kidney also was similar in both groups. Increasing the vitamin intake by giving 10,000 I.U. vitamin D3 or vitamin D3 palmitate per day resulted in earlier and more widespread calcific deposits. In rats, receiving 50,000 I.U. vitamins D3 or vitamin D3 palmitate per kg of diet, calcification in soft tissue was much less extensive than in rabbits. But again, no difference was seen between vitamin D3 and vitamin D3 palmitate. These results indicate, that vitamin D3 esters are not suitable as a less calcinogenic form of vitamin D3.

Animals↗

[Modern animal nutrition--dangers for the animal (author's transl)].

Undernourishment and malnutrition as well as nutritionally conditioned diseases are still the greatest risk factor for every domestic animal born. In less developed regions, overgrazing and monoculture crops pose new nutrition problems. In developed countries, animal populations are faced with new feedstuffs resulting from new technologies, with risks stemming from contamination and with exposure to various new substances. In order to allow for an evaluation of the modern feeding scene, several examples are given. Since a positive correlation between animal well-being and long term economic success is likely to exist, optimism seems indicated concerning the impact of modern feeding measures on the animal.

Animal Feed↗