Articles 81-90

Nutrition, physiological adaptation and re-introduction

A case study of the knot (Calidris canutus)

A. Brans BSc. *, Drs. J. van Gils1, B.B.H. van Wijk Bsc. Hons. MSc#, ir. H.J. Kuipers*

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

The influence of L-carnitine on nutrient retention in pigeons (Columba livia domestica) fed corn or peas

G.P.J. Janssens1, A. M. Abd-Ellah2, M. Hesta1, S. Millet, R.O.M. De Wilde1

1 Laboratory of Animal Nutrition, University of Ghent, Belgium
2 Department of Animal Hygiene, Assiut University, Egypt

The vitamin-like substance L-carnitine is an intermediary factor in fatty acid metabolism, which can be useful in racing pigeons. On the other hand, little is known about the utilisation of nutrients from different feedstuffs by these animals. This study wanted to clarify whether L-carnitine supplementation could affect the nutrient retention of corn and peas in non-active, adult racing pigeons. Two groups of eight female adult pigeons (Columba livia domestica L.) were fed restrictedly (25 g/d) with 100% corn or 100% peas respectively. Within each group, four pigeons received drinking water that was supplemented with L-carnitine (Lonzagroup., Basel, CH) at 2.5 g/L. After a 7d adaptation period, total collection of the excreta for each individual bird was performed daily during a 7d collection period.

Retention coefficients of corn and pea with and without L-carnitine supplementation.
Pea Corn L-Carnitine dose L-Carnitine dose Retention %: 0 g/L 2.5 g/L 0 g/L 2.5 g/L P-value
Dry matter 63.3±2.9 a 65.9±2.3 a 84.4±0.9 b 83.1±1.1 b Feed : > 0.001
Crude protein 37.2±1.7 a 38.1±6.7 a 61.1±2.2 b 47.6±4.8 c Feed*Dose : 0.006
Ether extract 76.8±1.7 a 76.9±3.4 a 84.5±3.9 b 84.1±2.5 b Feed : < 0.001
Crude fibre 14.2±6.9 a 22.0±3.1 a 17.9±4.5 a 12.9±6.5 a Feed*Dose : 0.038
N-free extract 85.4±1.0 a 85.1±0.9 a 92.2±0.1 b 92.4±1.0 b Feed : < 0.001
Organic matter 67.9±1.3 a 68.4±2.3 a 86.3±0.6 b 84.8±0.9 b Feed : < 0.001
a,b,c different indices in a row indicate a significant difference at p<0.05 (Scheffé-test).

Both on dry matter basis and on organic matter basis, corn was 30 % more digestible in pigeons than peas, which was consistent in the retentions of every analysed organic component except for crude fibre. For the latter an interaction between L-carnitine supplementation and the feedstuff used was significant, although no significant differences were found between the four groups. L-Carnitine supplementation had no effect on the crude protein retention in peas, but caused a significant decrease of crude protein retention in corn. It can be hypothesised that L-carnitine improved the efficacy of energy utilisation from fat and carbohydrates in corn, thus limiting the uptake of digestible amino acids for energy production. As peas are far higher in protein (and lower in fat), this effect could have been absent due to a higher need to use protein as an energy source. Nevertheless, this hypothesis should be checked in further research.

Changes in gastrointestinal transit time and pH in piglets around weaning.

V. Snoeck 1, N. Huyghebaert 3, E. Cox 1, A. Vermeire 3, J. Saunders 4, J.P. Remon 3, F. Verschooten 4, and B.M. Goddeeris 1,2

1Laboratory of Veterinary Immunology, Ghent University, Belgium
2Laboratory of Physiology and Immunology of Domestic Animals, KULeuven,, Belgium
3Laboratory of Pharmaceutical Technology, Ghent University, Belgium
4Department of Medical Imaging of Domestic Animals, Ghent University, Belgiumi

Management of the newly weaned piglet presents one of the most significant challenges to swine producers. The stress of weaning and movement to another environment increases the risk for disease, especially diarrhea, decreases the food intake and can lead to nutritional disorders (Pulske et al., 1997; Lecce et al., 1979).
To develop oral medications to treat piglets, a good knowledge of gastrointestinal (GI) parameters is needed. The objective of this study was to determine the GI transit time of pellets and the local pH in piglets at different moments around weaning. The transit time of non-disintegrating radio-opaque pellets was measured by radiography. The radiographs were analysed with a software programme to calculate the number of pellets present in the different parts of the GI tract. The pH was measured after slaughter at different sites along the GI tract with a pH probe.
In suckling piglets, the gastric emptying was faster and the colonic retention was greater than in weaned piglets: 75% gastric emptying was obtained during the first 1.5 to 3.5 h in suckling piglets, whereas 60% in 18 h, 58% in 15 h, and 73% in 7 h, were obtained 3 days, 1 week and 2 weeks postweaning, respectively. In suckling piglets, colonic accumulations to 73% were found, whereas in the weaned piglets the pellets maximally accumulated to 48%. Immediately after weaning, the transit times were markedly prolonged and subsequently shortened with the time postweaning: the 85 % excretion times were 175.5, 72.5 and 50.5 h, at 3 days, 1 week and 2 weeks postweaning, respectively.
Three weeks postweaning, the transit seemed no longer affected by weaning, as the transit times were similar to values previously reported in growing and adult pigs (Gregory et al., 1990; Potkins et al., 1991; Davis et al., 2001; Clemens et al., 1975) and retention appeared to be restricted to the stomach and the colon. In the stomach compartments of distinct pH were discerned. Along the first half of the small intestine and in the caecum, a negative correlation was found between the pH and the age of the piglet in contrast to the colon and rectum.
It can be concluded that weaning prolongs the transit times whereas the pH is not noticeably affected. These data are of crucial importance in the design and formulation of coating materials for orally administered vaccines and therapeutics.

Pulske J. R. et al., 1997. Livest. Prod. Sci. 51: 215-236.
Lecce J. G. et al., 1979. J. Anim. Sci. 48: 1007-1014.
Gregory P. C. et al. 1990. Br. J. Nutr. 64: 45-58.
Potkins Z. V. et al. 1991. Br. J. Nutr. 65: 391-413.
Davis S. S. et al. 2001. J. Pharm. Pharmacol. 53: 33-39.
Clemens E. T. et al. 1975. J. Nutr. 105: 759-768.

Seasonal variation of grazing available forage for domestics and wild ungulates in different alpine areas

P.Aceto1, A.Cavallero1, P.P.Mussa2, C.Abba2, R.Viterbi3, B.Bassano3

1Dept. of Agronomy and Selvicolture, University of Turin; Grugliasco, Italy
2Dept. of Animal Production, Epidemiology and Ecology, University of Turin; Grugliasco, Italy
3Gran Paradiso National Park, Italy

In the last years Alpine pastures have been progressively abandoned, because of the decreasing number of herds led to mountain summer pasture. The pastures in the mountains have both a productive and ecological role: grazing, when rational and controlled, may be a “natural” way for the conservation of floristic diversity and grassland management, especially in the protected areas.

The aims of this work were:
- to determine qualitative and quantitative characteristics of the grassland in the studied areas;
- to verify how grazing management affects the quality and the quantity of herbage mass.

Materials and methods
Three Alpine areas were chosen for this study, all in Piemonte region: two inside the Gran Paradiso National Park (Valli Orco and Soana) and one adjacent to Orsiera Rocciavrè Natural Park (Val Chisone). The following surveys were performed: - to determine the herbage mass available for grazing, and cattle and sheep grazing efficiency, 120 samples were collected from sample areas inside and outside exclosure cages by cutting with a portable lawnmower;

  • - organic matter digestibility (OMD; pepsine-cellulasi method) and crude protein (CP, Kjeldhal method) were determined on fortnight-collected samples, and the variation of the grassland quality during summer was assessed;

  • - fodder values (Pasture Value method, Daget & Poissonet,1972) for each vegetation type
    (ecofacies) were calculated (Cavallero et al., 2002);

  • Results
    The quality of the grassland was variable in the different areas and during time: ODM ranged from 41% to 77%, and CP ranged from 8% to 27%. The highest nutritive values were found during May and June, regardless the vegetation type, where cattle exploited the grassland twice during the grazing season. The lowest values were found in ungrazed areas. The herbage mass available for grazing was very variable too, ranging from 1,7 t ha-1 to 4,5 t ha-1. Its highest values were found in the areas grazed by cattle.

    A great influence was found on the vegetation composition due to grazing management. In most areas, summer grazing by cattle seemed to improve fodder quality, for their ability to completely exploit the grassland, resulting in good quality regrowth (high leaf/stem ratio). On the contrary sheep, which are very selective, might worsen botanical composition on the long term and induce a decrease of fodder quality during summer. Domestic animals exploit the grassland when the nutritive value has already declined. This means that wild ungulates are offered the best periods of the season for grazing. Finally, the rational grazing, in the present conditions, might have positive effects on wild ungulates feeding management and on enviromental conservation.

    Starvation of rumen bacteria and their shift-up growth under different condition

    A. Moharrery

    Animal Science Department, Agricultural College, Shahr-e-kord University, Iran

    The rumen liquor has been taken from a mature dairy cow with permanent rumen cannula, fed 50:50 mixture of grass and legume hays. The bacteria cells were separated from the rumen liquor by use of a centrifuge and kept on a phosphate buffer for thirty days. Two concentrations of glucose and two concentrations of isoacid (valeric and isovaleric) along with glucose were used for shifting-up growth after starvation. A roll tube method was used for maintenance and cultivation of bacteria and changes in turbidity were used as an indicator for reduction or increase of bacterial mass at various times. Results showed that bacteria cells could survive in buffer medium without any nutrient for 30 days, but after this period they needed a considerably long time for shift-up growth compared to normal conditions. The nutrient type influenced the time needed for shift-up growth. In low glucose concentration (3.3 mmol/ml of media) shift-up growth started after 12 hours of solution injection to the tubes and logarithmic growth kept on for the next 12 hours. In a high glucose concentration (6.6 mmol/ml of media) logarithmic growth started after 18 hours of solution injection and continued for the next 29 hours along with a higher bacteria concentration. Isovaleric acid (25.5 ìmol + 23 ìmol glucose per ml of media) and valeric acid (29 ìmol + 23 ìmol glucose per ml of media) initially showed the same effect on shift-up growth, but bacteria growth in valeric acid continued for 14 hours more than isovaleric acid along with a higher bacteria concentration.

    Diet selection by the White-naped Pheasant Pigeon Otidiphaps nobilis aruensis at the Barcelona Zoo

    Helena Marqués1, Maria D. Baucells2, Elena Albanell2

    1Parque Zoológico de Barcelona, Pq. de la Ciudadela s/n, 08003 Barcelona, Spain
    2Departament de Ciència Animal i dels Aliments, Facultat de Veterinària, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona Spain

    In 1999 the Barcelona Zoo held 53% of the total European captive population of white-naped pheasant pigeons Otidiphaps nobilis aruensis (a columbiforme endemic from Aru Isle - South-West of New Guinea). There is very little information about the biology and wild status of this subspecies, and it is poorly represented in captivity. This study was performed with 11 pheasant pigeons born at the Barcelona Zoo. A 14-days intake study was carried out and samples of the diet offered and refused by the birds were collected for proximate and crude energy analyses. Based on the generic food preferences of columbiformes, the pheasant pigeons of the study received a wide range of food types (10), allowing them to feed close to ad libitum. The aims of this study were to determine (1) the nutrient profile of the diet consumed by the captive population of the white-naped pheasant pigeons at the Barcelona Zoo, and (2) some of the factors that could have an influence on their diet selection. Due to the small sample size, there was a great variability among individuals. However, only the age and the origin of the birds had significant effects on some of the dependent variables (diet items, nutrient and water intake). Younger animals consumed significantly less grains than older animals. However, when looking at the whole group behavior, it was found that white-naped pheasant pigeons selected a diet with a great percentage of grains (over 35%). The average nutrient composition of the diet consumed was 18.9% crude protein, 8% fat, 4.6% crude fiber and 5.4% ash (on a dry matter basis). Comparing the results to the nutrient requirements published in the literature, the birds of the study consumed a diet that covered their energy, protein and fat requirements.

    Energy and nutrient intake, feeding behaviour and activity budget of Douc langurs (Pygathrix nemaeus nemaeus) in captivity

    K. Klumpe1, C. Schwitzer2†, W. Kaumanns2

    1Institute for Ecology/Conservation, University of Potsdam, Germany
    2Zoologischer Garten Köln, WG Primatology, Riehler Str. 173, 50735 Köln, Germany
    †corresponding author

    Douc langurs are very difficult to keep in captivity (Ruempler, 1998), which is mainly due to nutrition-related problems. Our study aims at providing first quantitative data on the nutrition and feeding behaviour of captive douc langurs, thus supporting the development of suitable diets for colobines in captivity.
    Individual food intake was recorded quantitatively over a period of three months in nine captive douc langurs. Nutrient and energy concentrations of the consumed diets were calculated and compared to results from relevant studies on other colobine species. Determinants which might influence food intake in the study group were assessed, an activity budget was drawn up, and dominance hierarchies were described. The diet consumed by the langurs consisted of 33% vegetables, 21% leaves, 21% fruits, 12% salad and 14% other food items. The results showed that the different foodstuffs differed in their acceptance by the animals. Leaves always had the highest amounts of leftovers. A greater diversity of leaves offered, however, correlated with a higher leave intake. Regarding the nutrient composition of the consumed diet, a high content of water-soluble carbohydrates and a low crude fibre content were obvious when compared to the diets of wild colobines. The amount of energy consumed by any of the studied douc langurs was lower than the calculated energy requirement.
    During the daily observation time, the animals spent 56% with resting and sleeping, 22% with eating, 6% with locomotion, and 3% with grooming. The results are mainly discussed with regard to the presumably sub-optimal energy intake of the studied douc langurs. The fact that a considerable proportion of the offered leaves was not consumed by the animals might be indicatative of the leaves’ quality (palatability, taste etc.) not matching with the requirements of the langurs.

    Ruempler U., 1998. Int. Zoo Yb. 36: 73-81.

    Epidemiologic study of hospitalized dogs voluntary food intake

    Nathalie Priymenko*, Isabelle Lesponne**, Claire Besson*, Patrick Verwaerde**

    * Unity of Nutrition, ** Unity of Anesthesia and Critical care, National Veterinary School of Toulouse, 23 chemin des Capelles, 31076 Toulouse Cedex, France

    Unusual environment as veterinary hospital can generate different stresses in dogs. Often considered as less relevant clinically in dogs than in cats, stress induced by hospitalization conditions could reduce voluntary food intake in hospitalized dogs. The aim of the present study was to investigate the daily spontaneous food intake in hospitalized dogs and to define the external factors that could be responsible for a lesser intake. This experiment has been performed as an open trial, including all dogs admitted in the National Veterinary School of Toulouse that required a more than 48 hours hospitalization. All dogs requiring enteral tube support or parenteral nutrition were excluded. Forty-three dogs were included during a period of 16 days. Notification of the nature and quantity of daily food intake in standard hospitalization conditions was used to evaluate spontaneous food intake. From a clinical point of view, body weight, pain score and clinical parameters were recorded every day.
    Included dogs were 6.0 ± 4.4 years old [0.3-14 years] and were classified in large breed dogs (19/43), medium sized dogs (4/43) and small breed dogs (20/43) including poodle dogs (5/43). Considering their initial body condition, dogs were thin (35%), normal (51%), overweight (7%) and obese (7%). Twenty three per cent of them had clinical muscular atrophy. Hospitalization causes were gastrointestinal disorders (10/43), general surgery (10/43) and ophthalmology troubles (8/43). Other dogs were hospitalized for neurological or orthopedic disorders (6/43), or for infectious (3/43), urologic (2/43), cardiologic (2/43), endocrine (1/43) and skin (1/43) diseases.
    In these conditions, mean spontaneous food intake was 7.61 ± 0.69 g/kg/d (dry matter basis) during hospitalization period. During the four initial days of hospitalization, voluntary intake covered 40.3, 68.5, 62.7 and 73.9% of the dog’s resting energy requirement (RER = 70.BW0.75). After the fourth day, voluntary intake appeared above the RER, but remained under the daily energy requirement1 for ill dogs, except of the 6th day of hospitalization (DER : as described1). The body weight was slightly decreased during hospitalization (maximal decrease -4.4% at the tenth day). In all evaluated contributing factors, pain score or Elizabethan collar presence failed to influence spontaneous food intake. Casuals of hospitalization analysis revealed that dogs with gastrointestinal and ophthalmology disorders as well as dogs submitted to general anesthesia had a lower energy intake, than dogs suffering other diseases or not submitted to anesthesia.
    We observed that small (< 10 kg) and great (> 30 kg) breeds ate less than medium breeds. Physical aspect of meal significantly influenced voluntary food intake, since spontaneous intake was 8.42 ± 1.07 g/kg/d and 12.60 ± 1.41 g/kg/d (dry matter basis) with canine dry food and canned food, respectively. Thus, our study shows that canine feeding behavior can be significantly influenced by hospitalization conditions. Different risk factors such as breed size, anesthesia procedure and nature of disorders appear to be clinically relevant in their influences on spontaneous food intake. Those factors must incite veterinarian to monitor food in hospitalized dogs. 1 Crowe: Vet Med Small Anim Clin 1988; 83:1224-1249.

    Some Preliminary Observations on Herbivorous Insect Composition: Nutrient Advantages from a Green Leaf Diet?

    Ellen S. Dierenfeld

    Department of Wildlife Nutrition, Wildlife Conservation Society, Bronx, NY USA

    Most insectivores maintained in captivity are fed a limited variety of species that have been raised on grain-based diets, comprising primarily the larvae of meal beetles (Tenebrio molitor or Zophobas morio), crickets (Gryllus sp.) of various instars, and the larvae of the wax moth (Galleria mellonella). Almost all published reports of invertebrate composition demonstrate them to be a poor source of calcium (Anderson, 2000; Klasing et al., 2000), with an imbalanced Ca:P ratio. Chemical analysis of silk moth larvae (Bombyx mori) and stick insects (Baculum extradentatum and Eurycantha calcarata), raised on a diet of white mulberry (Morus alba) leaves, revealed high Ca concentration (silk moth larvae 0.9%, gravid female stick insects >2% Ca, dry matter (DM) basis) as well as Ca:P ratios >1:1. Similar to other insects analyzed (Dierenfeld et al, 1995; Barker et al., 1998), carotenoids were present but minimal or no vitamin A activity was detected in extracts from these samples. In contrast, vitamin E concentration was high (>450 IU/kg DM) in both silk moth larvae and stick insects. Mulberry contains high levels of Ca and vitamin E (Dierenfeld et al., 1990; Zootrition, 2001), and may be a good source of these nutrients for herbivorous invertebrates. Dietary fibre (measured as neutral detergent fibre) ranged from moderate to high (12 to 50% of DM in silk moth larvae and stick insects, respectively), and encompassed ranges reported for different life stages of invertebrates consumed by anteaters and other insectivores in nature (Redford & Dorea, 1984; Oyarzun et al., 1996). Fibre has been shown to provide energy to insectivores, and promotes improved fecal quality and gastrointestinal health (Graffam et al., 1998).
    Additionally, the dietary bulk of chitinous exoskeletons and/or even the plant cell walls found in gut contents of herbivorous insects may provide a nutrient dilution effect to alter otherwise excessively energy-dense diets. The larvae of the silk moth and adult stick insects, both feeding on mulberry, may be useful insects for feeding captive insectivores. Proximate constituents are comparable with those of other invertebrates commonly used in zoo feeding programs; a diet of mulberry leaves, however, may enhance dietary fibre and particularly vitamin E and Ca concentrations in these alternative feeder insects.

    Anderson S.J., 2000. Zoo Biol. 19:1-10. Barker D. et al., 1998. Zoo Biol. 17:123-134.
    Dierenfeld E.S. et al., 1990. Proc. AAZV Ann. Meet., Brownsville, TX. Pp. 196-197.
    Dierenfeld E.S. et al., 1995. Verhandl. Ber. Erkr. Zootiere 37:245-249.
    Graffam W.S. et al., 1998. J. Nutr. 128: 2671S-2673S.
    Klasing K.C. et al., 2000. J. Zoo Wildl. Med. 31:512-517.
    Oyarzun S. et al., 1996. Zoo Biol. 15: 509-524.
    Redford K.H. and J.G. Dorea, 1984. J. Zool. 203:385-393.
    ZootritionTM software, 2001. Wildlife Conservation Society.

    The role of insects in primate nutrition: how is chitin utilized?

    Charlotte O’Sullivan,1, Mauvis Gore1, Sophie Foley,2, Kathy Velander,2

    1Animal Conservation and Research Dept., Royal Zoological Society of Scotland,
    2School of Life Sciences, Napier University, Edinburgh, Scotland

    The study of mammalian insectivory has been neglected in contrast to folivory, frugivory and grazing mammals. A major component of insects is their chitinous exoskeleton, but there is little evidence of how mammals may break down large structural carbohydrates, such as those found in the chitin. Insects form a large part of the diet of callithrichids, small, New World primates. Data on the nutrient composition of insects consumed by callithrichids is scarce and the proportion of insects digested is not known. This information is important for the conservation of callithrichids both in the wild and in captivity. The study focused on members of the callithrichid genus, the range providing an overview of their insectivory. Work on the anatomy, mechanical, biochemical and microbial processes was carried out on individuals culled for purposes other than this study. The chitin content of a variety of insects were analysed and a chitin budget determined for the callithrichid species. The results were assessed in relation to captive and wild diets.
    The proportion of chitin in insect body parts was determined and related to preference of their ingestion. Methods were established to examine chitin digestion by microbial, biochemical and mechanical means. Ten samples of four insect species were given to each primate species. The course of chitin digestion through the gastro-intestinal tract of callitrichids was mapped. Results produced an exact baseline chitin budget from 200 samples from 10 common marmoset, Callithrix jacchus, and an estimated chitin budget for other callitrichid species, including Geoffroy’s marmoset, C. geoffroyi, pygmy marmoset, Cebuella pygmaea, cotton top tamarin, Saguinus oedipus, golden headed lion tamarin, Leontopithecus chrysomelas, Goeldi’s monkey, Callimico goeldii. Analyses of gut content revealed how callitrichids digest insects and the importance of insects in their diet was determined.