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MINEROL AS A MEANS OF NORMALIZATION OF BLOOD LIPID EXCHANGE IN BIRDS

L. Borisenko1 and L. Mhitarjan2

1The Institute of Veterinary Medicine, ul. Donetskaya 30, 03151 Kyiv, Ukraine; 2The Institute of Cardiology, 5 Timoshenko St., ap. 21, 04212 Kyiv, Ukraine

Improper nutrition due to the deficiency of certain trace elements in food is a reason of many human and animal diseases. The course and the outcome of pathological process in many respects depend on state of blood microcirculation. This circulation is responsible for receipt of substances, necessary for normal function of cells and cleaning them from slags. The purpose of the present research is to find out the influence of multimineral component "MINEROL" on lipid concentrations in blood - factor, on which state of blood microcirculation mainly depends. The medical and preventive supplement MINEROL is a modified natural material with definite absorptive characteristics, containing more than 60 elements including (by mass): silicon, calcium, magnesium, manganese, potassium, sulfur, phosphorus, iodine, nickel, chromium, lithium, zinc, vanadium, cobalt, selenium. The influence of MINEROL on parameters of lipid exchange in chickens is described. There were several age groups (young and old), 20 birds of the same type in each. The following parameters of lipid exchange were studied: general cholesterol, alpha-cholesterol, beta-lipoproteins, triglycerins. The research was conducted with automatic analyzer "Express -550 " (Ciba-Corning, United Kingdom). Application of MINEROL in the amount of 1 % of daily diet during two months resulted in diminution (Ð < 0,01) of general cholesterol, beta-lipoproteins, triglycerinsin in old chickens, and a downward tendency of these parameters was observed in young birds. It is known that increased levels of investigated blood lipids lead to the hardening of arterial walls and consequently to deterioration of blood microcirculation. The diminution of these parameters with simultaneous minor increase of alpha-cholesterol parameter, which was observed after application of MINEROL, is evidence of a normalizing effect of this supplement. It was also discovered that usage of MINEROL promotes a decrease of internal fat in organism of old birds almost in twice and actually has no influence on amount of fat in young birds. Multimineral component MINEROL ensures normalization of lipid exchange in birds. It is particularly evident in case of older chickens, and gives the grounds for MINEROL application as hypo lipid and geroprotective means in captive birds diet in the zoo.

NUTRITION, PHYSIOLOGICAL ADAPTATION AND RE-INTRODUCTION A CASE STUDY OF THE KNOT (Calidris canutus)

Brans1, Drs. J. van Gils2, B.B.H. van Wijk1* and H.J. Kuipers1

1Van Hall Institute, Dept .Animal Management, P.O. Box 1528, 8901 BV Leeuwarden, The Netherlands; 2NIOZ, P.O. Box 59, 1790 AB Den Burg, The Netherlands

The ability to adapt to changes in the environment plays an important role in the survival of species. These adaptations can take place within short time lapses, resulting in repeated physiological changes of the organism within one lifespan. The adaptation of migratory bird digestive tracks and flying muscles is an example. The ability to show these adequate changes in physiology may determine the success of individuals in a competing environment, which will be most important in re-introduction programs. Size reduction of the knot’s (Calidris canutus) digestive track takes place before the start of the migration period. At the same time the flying muscles as well as the heart muscles are increased in size. This adaptation is directed toward the effective use of energy. The trade-off between physiological capacity and environmental requirements is essential for individual as well as long term species survival. The natural diet of the Knot consists of small shells and other organisms. The shells are found in the top sediment layer of the wetlands where they forage. This prey is swallowed as a whole. The shells are crushed using stomach muscles. This requires strong stomach muscles. Training induces the increase of the stomach musculature. Taking in larger prey incites these muscles to increase. Reduced food intake during the migration period results in reduced stomach size. During this period the Knot relies on smaller, softer shelled prey. Research showed that the food intake rate in the Knot depends on prey size and shell mass. Stomach size did not influence food intake rate. To crack larger prey specimen stronger and thus larger stomachs are required. The foraging behaviour of the Knot in-situ is adapted to this physiology. Translating these results to the management of the Knot ex-situ, and to comparable bird species there are two major lessons to be learned. Especially so where re-introduction is a long-term option. First the willingness of the birds in captivity to accept pelleted food must not automatically lead to the use of such food. The advantage of controlled diet composition, reduced risks of diseases and such must be balanced against the possible long-term consequences of such easily digested pellets. The lack of stimulation of the stomach muscles when feeding pellets can prove to have long term lasting effects on the survival rate of the re-introduced animals. Second the increased handling time of natural food is a distinct advantage in the prevention of stereotypic behavior. Diets complemented with natural food must be considered. Providing shells hidden in a sandy substrate in a well-controlled manner is not only environmentally enriching, but also assures natural behaviour and physiological development.

TANNINS IN THE NUTRITION OF WILD ANIMALS: A REVIEW

M. Clauss

Institute of Animal Physiology, Physiological Chemistry and Animal Nutrition, Munich Veterinaerstr. 13, D-80359 Munich, Germany.

The diet of many free-ranging wild animals contains significant amounts of tannins and other polyphenolics. Historically, attention has mostly focused on the negative effects of tannins on herbivores. Tannins reduce diet digestibility by impeding bacterial fermentation processes and by increasing endogenous losses; they impair the use of absorbed nutrients, can be toxic and reduce the palatability of many forages. Therefore, they act as feeding deterrants and have often been interpreted as a part of the anti-herbivore defense of plants. However, recently the antioxidant and cardioprotective potential of tannins and other polyphenolics has been emphasized in human nutrition, and polyphenolic extracts can nowadays be found amongst other human diet supplements in drug store shelves. Wild animals in captivity are mostly fed a diet that is relatively low in tannin content. While this might suit the evolutionary adaptation of grazing species, especially the browsers ould be hypothesized to face a situation where the antioxidant support from their natural forage that they have adapted to is missing in captive diets. Other positive effects have been demonstrated: Limited levels of tannins can reduce the protein degradation in the forestomach of ruminants and thereby increase the flow of more valuable amino acids to the small intestine. Tannins are effective against bacteria, fungi and viruses. Tannins are known to chelate iron in the gut and reduce its availability. In the wild, many animals therefore would have had to adapt to very low iron availabilities, whereas a captive diet would offer a relatively unrestrained iron provision. Tannins are known to prevent bloat in domestic ruminants. Tannins are effective against gastrointestinal stages of helminth parasites. Several observations from zoological gardens can be compared to these properties. During the transition from the wild to captivity, i.e. from a natural to an artificial diet, leaf-eating Colobine monkeys suffer from gastrointestinal disorders that are associated with bloat, enteritis, and helminth infections. Bloat conditions are also observed in other leaf-eating species in captivity, like sloths or giant eland. It has been observed that some browsers are, in zoo situations, especially susceptible to parasite infections and enteritis. Some browsing species develop an iron storage disease in captivity. It is tempting to suggest the lack of tannins as an underlying common factor. The potentially beneficial effects of a more natural dietary tannin supply for zoo animals should be further investigated.

N-6 AND N-3 POLYUNSATURATED FATTY ACIDS IN THE NUTRITION OF WILD ANIMALS : A REVIEW

M. Clauss1 and K. Ghebremeskel2

1Institute of Animal Physiology, Physiological Chemistry and Animal Nutrition, Munich Veterinaerstr.13, D-80359 Munich, Germany; 2Institute of Brain Chemistry and Human Nutrition, University of North London, Holloway Road, London, N7 8DB, United Kingdom

Polyunsaturated fatty acids (PUFA) have been recognised to be vital for growth, development and health. Linoleic (LA, 18:2n-6) and alpha-linolenic (ALA, 18:3n-3) acid, the respective parent compounds of the n-6 and n-3 families, cannot be synthesised by animals and must be provided in the diet. Animals have the ability to convert these fatty acids to their respective long-chain metabolites through series of desaturation and elongation steps with variable efficiency. The main sources of LA are vegetable and seed oils, nuts, seeds and meat. In contrast, ALA is obtained primarily from green leaves, grass, seaweed and fish. When wild animals are brought into or kept in captivity, they are maintained on foods whose nutritent composition is qualitatively and quantitatively different from what they eat in their natural habitat. With regard to lipids, this nutritional practice often results in high intakes of saturated fat and low consumption of total and n-3 PUFA. This is particularly evident in zoo ungulates in which the inevitable scarcity of browse and green leaves, and thus the low provision of ALA, is manifested in abnormal tissue fatty acid patterns. Total and n-3 PUFA are reduced, and n-6 is increased. A similar shift in the fatty acid pattern of body tissues has been observed in fish, reptiles, birds, and other mammals. Given these data, it is reasonable to suspect a low n-3 PUFA status in many zoo animals. The contrast in intakes of n-3, n-6 and saturated fatty acids in captive and domestic animals as compared to their free-ranging conspecifics appears to mirror the transition in human nutrition from paleolithic conditions to modern western diets. In man, the dietary habits of ‚Western society‘ are associated with a high incidence of cardiovascular disease, hypertension, diabetes and some types of cancer. Reports of clinical problems associated with n-3 deficiencies are rare in zoo animals. In man and experimental animals, insufficiency and impalance of n-6 and n-3 fatty acids leads to various clinical and sub-clinical problems including growth retardation, reproductive failure, hair loss and skin lesions, haematological disorders, impaired immune response and vascular dysfunction. A low n-3 supply might, in zoo animals, contribute to vascular disease, to skin or moulting problems, influence hibernation patterns, and aggravate cases of enterotoxemia. It might also influence fertility. Essential fatty acid deficiency has been shown to impair sperm development, egg hatchability, and fetus and newborn survival. Mammalian and avian sperm contains large proportions of PUFA, which is to a degree influenced by the dietary PUFA supply. While sperm of low fertility is often characterized by a high n-6:n-3 ratio, sperm of higher quality has higher PUFA levels and especially lowered n-6:n-3 ratios, i.e. contains more n-3 PUFA. It has been shown that the feeding of a n-3 PUFA rich diet can improve sperm quality and fertility in fowl and man. The potentially beneficial effects of a more natural dietary fatty acid supply for zoo animals should be further investigated.

FEEDING BROWSE TO LARGE ZOO HERBIVORES: HOW MUCH IS “A LOT”, HOW MUCH IS “SUFFICIENT”?

M. Clauss1, E. Kienzle 1 and H. Wiesner2

1Institute of Animal Physiology, Physiological Chemistry and Animal Nutrition, Munich, Veterinaerstr. 13, D-80359 Munich, Germany; 2Zoological Garden of Munich, Munich, Germany

Diet evaluations in captive browsers are often confounded by the fact that the amount of browse offered is difficult to quantify, especially if whole branches are fed. For a diet survey in captive moose (Alces alces), we established correlations between the diameter at point of cutting of a branch and the amount of foliage and edible twigs on it. Eight different species of trees were investigated. The correlations were allometric, and highly significant. For all tree species combined, e.g., the correlations of the total weight of a branch (y1) and the weight of its leaves (y2) with the diameter at point of cutting (x) were y1= 0.84 x1.94 and y2= 0.48 x2.48, respectively. Given the according equations, it was only necessary to measure the diameter of the branches fed in the institutions that participated in the diet survey. Examples are given for diet evaluations based on the estimation of edible browse derived from the equations.