Articles 141-148

Case report: Effects of extruded linseed supplementation on the milk fatty acids pattern of dairy ewes

P. Rondia(1) , Y. Larondelle(2) , Ch. Delmotte(3) , F. Dehareng(4) , J. Fabry(1) , J. Laloux(5) , X. Derycke(6) , N. Bartiaux-Thill(1)

(1)C.R.A.Gx., Département Productions et Nutrition animales UCL, Faculté d’ingénierie biologique, agronomique et environnementale,
(2)BNUT, (4)GENA
(3) DG 6, Service Développement production animale
(5)C.R.A.Gx., Département Qualité des Productions Agricoles
(6) Haute école provinciale de Charleroi – Université du travail, Ath

Conjugated linoleic acids (CLA), having positive human health effects, are specifically synthetised by ruminant. Numerous studies have demonstrated that cow’s milk could be the most important source of CLA. Depending on the type of feed ingested, cow’s milk can also be a valuable supplier of omega-3 (w3) fatty acids for human. To our knowledge, similar information on milk composition of dairy sheep is very scarce. The aim of the experiment described there was to evaluate the influence of extruded linseed added to the diet on the milk fatty acids pattern of dairy ewes, particulary on CLA and w3 concentrations.

The experiment, divided into two periods of three weeks, was conducted on a 80 dairy ewes flock splited in two comparable groups (23 Belgian Milk Scheep and 17 Lacaune). Each period included 16 days of adaptation to the diet followed by 5 days of milk tank sampling. 10% of the concentrate included in the experimental diet (E) was composed by extruded linseed.This feedstuff was replaced by copra cake in the control diet (C). After the first period, diets were permuted between groups. Whatever the diet, each sheep received daily 2.2 kg of concentrate and had a free access to hay.

Extruded linseed supplementation to ewes induced significant increases of CLA, w3, monounsatured fatty acids and polyunsatured fatty acids concentrations in sheep milk,
respectively + 98% (1.17 vs 0.59)*, + 147% (1.51 vs 0.61)*, +32% (23.55 vs 17.90)* and +86% (5.97 vs 3.22)*. Concomitantly, we observed a 11%-decrease in saturated fatty acids levels (70.47 vs 78.88)* and a 54%-increase in the stearic acid concentration (10.22 vs 6.65)*. A 39%-reduction in the w6/w3 ratio (1.81 vs 2.96) was also observed. Similary to cow’s milk, the major isomer of CLA in the sheep milk was 9-cis, 11 trans (81.49 and 84.92% of total CLA for E and C, respectively). For all fatty acids mesured, including CLA, differences between E and C were highly significant (p<0.05).

Daily milk productions were not statistically different between diets (p=0.166) and reached respectivelly 2.00 and 2.05 kg of milk/ewe/day for E and C. Diets had no effect on milk fat content (p=0.822), wich reached respectivelly 6.42 and 6.46 g/100 g of milk for E and C. Nevertheless, E induced a higher milk protein content than C (5.36 vs 5.20 g/100 of milk). These observations are in contradiction with results of previous studies showing a reduction in milk fat (Griinari et al., 1998 ; Chouinard et al., 1999) and in milk protein with high polyunsatured fatty acids in cow diet (Focant et al., 1998). This experiment was carried out under a project financed by « le Ministre Wallon de l’Agriculture et de la Ruralité, Direction Générale de l’Agriculture ». We deeply appreciate the contribution and helpfulness of Pierre Artoisenet for flock management.

Chouinard et al., (1999), J. Nutr., 129, 1579-1584
Focant et al., (1998), J. Dairy Sci., 81, 1095-1101
Griinari et al., (1998), J. Dairy Sci., 81, 1251-1261
* Data were expressed as % of total fatty acids. Comparisons were made between E and C diets.

Black tea consumption, iron status and risk for cardiovascular disease

David J. Baer, Joseph T. Judd, and Michael Davies

U.S. Department of Agriculture, Agricultural Research Service, Beltsville Human Nutrition Research Center, Building 308, Beltsville, MD 20705, USA

Several studies have demonstrated that black tea consumption decreases iron absorption. Tea consumption also has been inconsistently associated with a reduced risk for cardiovascular disease in human epidemiologic research. These observations on risk for cardiovascular disease also may be linked to iron status, or to other mechanisms. Despite the studies investigating the effect of tea on iron absorption, there are few data on the effect of tea on measures of iron status. As part of a dietary intervention study, 15 individuals (Homo sapiens) were fed a diet of fixed composition and three beverages: 1) black tea, 2) flavored water with caffeine (to match the caffeine content of the tea) and 3) flavored water without caffeine. The placebo beverages were similar to the tea with respect to color and taste. Each individual consumed five daily servings of each treatment beverage during three separate three-week periods, in a randomized crossover design study. The effects tea on iron status and blood lipids was measured at the end of each period. There was no effect of treatment on concentration ceruloplasmin or transferrin, and no effect on red blood cell count, white blood cell count, erythrocyte indices, hematocrit, and differential blood count. However, consumption of tea resulted in a 10.3 percent decrease in LDL cholesterol compared to placebo beverage having caffeine at the same concentration as in the tea. Triacylglyceride and HDL cholesterol were not different among treatments.

The role of ferritin in iron storage in birds

G.M. Dorrestein1, Y.R.A. van Zeeland1, A.B. Vaandrager2, P.C.J. Dorrestein3

1Dept of Vet Pathology, and 2Dept of Biochemistry, Faculty of Veterinary Medicine, Utrecht University, The Netherlands
3Dept of Chemistry, Cornell University, Ithaca NY, USA

Iron overload is a condition which is found commonly in certain species of birds, such as mynahs and toucans (for a review see Cork, 2000). Species susceptible to developing iron overload generally have a diet consisting predominantly of insects and/or fruits, which are food sources with a low iron content (4). Given these facts the storage problem is likely to have a species broad genetic background, in which the regulation of the iron intake in the proximal intestine, where iron is normally absorbed and transferred to the body plays a central role. The possibility of an altered modulation and/or regulation of iron absorption, by a socalled ‘mucosal block’ was proposed and later confirmed in experimental research (2,3). One of the proteins or iron responsive elements (IREs) suggested to function in the mucosal block is ferritin (ftn). As an iron storage protein ftn and its degradation product hemosiderin function as the most important iron binders in livercells. The aim of this study was to find quantitative and/or qualitative differences in ftn in intestinal mucosa cells and liver in different species that could lead to a better understanding of the role of ftn in iron storage in birds.

In this study ftn, Fe, iron binding capacity (IBC) and total IBC were quantified in intestinal mucosa and liver of the following avian species: chicken (G. domesticus), turtledove (Str. d. decaocto), hill mynah (G. religiosa) and river mynah (Acridotheres t. tristis). Liver ftn was isolated in the same species as well as in pigeon (Columba livia), a sulphur-breasted toucan (Ramphastos vitellinus) and a common trumpeter (Psophia crepitans, fam. Psophiidae). These ftns were characterized for quantity (mg/mg protein), molecular weight (mw in kDa), ratio and mw of the L- and H-subunits and purity (%).

The results show significant differences between ftns of birds in amount, iron binding characteristics, mw’s and in composition of ftn (H/L ratio), both in liver and mucosal cells. The most important conclusions to be drawn from our results are 1. There is no difference in the amount of ftn (mg/mg protein) in the intestinal mucosa cells between the doves and mynah species. The chicken has a very high amount of ftn in the mucosal cells. 2. Toucan, trumpeter and hill mynah show high amounts of ftn in the liver compared to chicken, dove and pigeon, but the river mynah had less than 5% of the amount in the hill mynah. 3. The TIBC of ftn in mynahs is twice the capacity of dove and chicken both in mucosa and livercells. The average Fe saturation of ftn in the mynah livers was 71-74%, in dove and chicken 41-42%. In the intestinal mucosal cells the saturation was not different (average 58-75%). 4. There was a large difference in mw of liver ftns between chicken, dove, pigeon (369,390,393 kDa) and hill mynah, toucan, trumpeter (492, 494, 471 kDa). This is a reflection of the difference in H/L ratio (0.33, 0.25, 0.33) and (0.10, 0.08, 0.10), respectively. In the mucosa cells the H/L ration was 5.0, 3.0 for chicken and dove and 1.5, 0.35 for river- and hill mynah The possible role of ftn in iron storage will be discussed in the context of earlier research (3).

Cork S.C., 2000. Avian Pathology 29: 7-12.
Dorrestein G.M. et al., 1992. Proc AAV pp.108-112.
Mete A. et al., 2001. Avian Pathology 30: 481-488.
Otten B.A. et al., 2001. JAMS 15:194-196.

Biotin is the first limiting nutrient for the growth of salmonella in chickens and iron is second limiting.

Kirk C. Klasing

Department of Animal Science, University of California, Davis, CA, USA

In mammals, iron is considered to be the “first limiting” nutrient for the growth of most pathogenic microbes in body fluids due to its tight chelation by transferrin and lactoferrin. Birds lack the mammalian functional equivalent of lactoferrin and previous results in chickens indicated that the addition of iron did not impair the bacteriostatic properties of serum. It is possible that other nutrients might become limiting for growth of pathogens in avian body fluids. Avidin has an extraordinary high dissociation constant for biotin of 10-15 and is found in birds, but not mammals. This protein has the highest non-covalent binding affinity found in nature. Plasma biotin concentrations are markedly elevated during the acute phase response of chickens to bacterial challenges. Biotin is required for the growth of many microbial pathogens of birds, including species of Candida, Listeria, Staphylococcus, Clostridia, Streptococcus, Salmonella, E. coli, and eucaryotic parasites. To evaluate the role of avidin in limiting the growth of the chicken pathogen Salmonella typhimurium by withholding biotin a series of in vitro and in vivo experiments were conducted. Macrophages isolated from the peritoneal cavity and stimulated with S. typhimurium LPS expressed avidin mRNA and their conditioned medium inhibited the growth of S. typhimurium. This inhibition was reversed by the addition of biotin. Serum from chickens undergoing an acute phase response to S. typhimurium LPS inhibited S. typhimurium growth and this bacteriostatic property was reversed by biotin. The addition of iron did not increase the proliferation of S. typhimurium in chicken acute phase serum in the absence of biotin. However, iron significantly increased proliferation in the presence of biotin. These results indicate that biotin is the first limiting nutrient for the growth of S. typhimurium in the blood of chickens and iron may be second limiting.

Kunnas, T. et al. 1993. Biochimica et Biophysica Acta 1216: 441-445.
Klasing, K. C. 2002 et al. FASEB J: 251: 2413.
Klasing, K. C.1998. Poult Sci 77: 1119-1125.

A process-based model to estimate air emissions from animal feeding operations

Jamie S. Jonker1, Christopher Rogers1, Perry R. Hagenstein2, Robert G. Flocchini3, Charlotte Kirk Baer1

1Board on Agriculture and Natural Resources, National Research Council, Washington, DC 20418;
2Institute for Forest Analysis, Planning, and Policy, Wayland, MA 01778;
3Crocker Nuclear Laboratory, University of California – Davis, Davis, CA 95616

Over recent decades in the United States, more livestock production has occurred on fewer farms. Between 1982 and 1997, animal feeding operations (AFOs) decreased by 51 percent while livestock production increased 10 percent because of increasing production on these fewer farms. During this time, geographic concentration of livestock production also has occurred. This type of geographic concentration has placed increasing pressure upon the U.S. Environmental Protection Agency (EPA) to regulate air emissions from AFOs because of odor and health concerns.

In 2002, the U.S. National Research Council (NRC) convened a Committee on Air Emissions from Animal Feeding Operations to conduct a scientific assessment for estimating air emissions of various pollutants (hydrogen sulfide, ammonia, odor, volatile organic compounds, particulate matter, nitric oxide, and nitrous oxide) from AFOs. The study included a review of the model farm construct proposed by EPA to estimate air emissions at individual AFOs. The committee suggested a process-based model farm approach that builds upon EPA’s model farm construct using mathematical modeling and experimental data to simulate conversion and transfer of reactants and products through the farm enterprise. This process-based model farm approach would incorporate mathematical modeling to represent the interactions among the system components.

In this paper, the process-based model farm approach recommended by the NRC committee was examined utilizing data from a case-study dairy farm in New York State with a whole-farm nitrogen mass balance. The EPA model farm construct estimated nitrogen air emissions to be 22 300 kg per year while the process-based model farm approach predicted 30 100 kg. A sensitivity analysis was performed with the process-based model examining effects of precision feeding, liquid manure storage covering, land application with soil incorporation, and combinations of all three.

Feeding amino acids has been shown to decrease nitrogen excretion from dairy cattle up to 26,0 percent. With simulating use of this technology on the case study farm utilizing the process-based model farm approach, nitrogen air emissions were predicted to decrease by 22,3 percent. Covering liquid manure storage system can reduce ammonia emissions by 80 percent for swine effluent. If equally applicable to dairy effluent, predicted nitrogen air emissions for the case study farm were reduced by 16,4 percent. However, nitrogen leaching under this scenario would increase by 1 300 kg per year. Various combinations of these technologies were predicted to reduce nitrogen air emissions from the case study farm by up to 74,5 percent.

Model farms may be a useful device for describing groups of AFOs with similar production and management practices by a single well-defined farm. A process-based model farm approach (NRC, 2002) builds on EPA’s model farm construct by using mathematical modeling, experimental data, and mass balance constraints to simulate conversion and transfer of reactants and products through the farm enterprise. Incorporation of water quality models into a process-based approach may provide the potential water quality impacts of different air quality management practices.

Dietary considerations for iron storage disease in birds and implications for high vitamin A contents of formulated bird foods.

Debra McDonald

Démac Wildlife Nutrition, Healesville, Victoria, Australia, 3777

Iron storage disease (ISD) is problematic for many frugivorous and insectivorous birds maintained on commercially formulated foods. High dietary iron has been implicated as a possible cause in the promotion of iron storage with recommendations for dietary levels of iron below 100 mg/kg, preferably below 25 mg/kg. Various other factors have been considered in the development of this disease, including genetic predisposition, immunological stress, viruses and nutrition. Nutritional aspects include enhancement of iron uptake by high levels of vitamin C and saturated fats, and an increase in lipid peroxidation by low levels of vitamin E (exacerbated by an excess of vitamin A). While plant products contain provitamin A in the form of carotenoids (the conversion of which is regulated by the body) and vitamin A levels are negligible in insects, commercial foods for psittacines are generally high in vitamin A (Kaytee, 12 IU/g; Mazuri, 8.33 IU/g; Nutribird, 12 IU/g; Pretty Bird, 17 IU/g, Roudybush, 8.75 IU/g) when compared with poultry requirements of 1.5-4.0 IU/g, with few exceptions (HBD International, 1.44 IU/g). Studies of psittacines maintained on diets low in preformed vitamin A, indicate a significant increase in productivity and a decrease in the incidence of ISD in these birds. Some softbill aviculturalists also use cheap dog food low in preformed vitamin A, without any obvious negative affects.
In contrast to vitamin A, the presence of carotenoids in microsomal membranes partially inhibits the loss of á-tocopherol, especially during the late phase of oxidative stress, with âcarotene decreasing phospholipid hydroperoxide production. However, astaxanthin is twofold more effective than â-carotene at inhibiting the production of lipid peroxidases and âcarotene also increases the absorption of iron. Canthaxanthin is another carotenoid compound that is supplemented to promote feather pigmentation in birds such as flamingos and scarlet ibis. However, canthaxanthin alters tocopherol status and decreases glutathione peroxidase, which functions together with the peptide glutathione to protect cells against the destructive effects of hydrogen peroxide. Dietary supplementation of canthaxanthin in flamingos may by implicated in the development of ISD. It is possible that the high levels of vitamin A (retinyl palmitate esters) in these commercial products are contributing to iron storage disease in birds and replacement of vitamin A with specific carotenoids may be warranted. Given the differences in action of carotenoids such as â-carotene, astaxanthin and canthaxanthin, it is crucial that dietary requirements of birds for specific carotenoids are identified. It is evident that further research on this topic is required.

Observations regarding the capacity of selenium to intensify the activity of vitamin E in chickens encephalomalacia

Adriana Orasanu, Jenica Bucur, N.Alexandru, St.Nicolae

Institute of Diagnosis and Animal Health, Bucharest, Romania

Encephalomalacia is a disease whit a controversy about its etiopatogenesis that still exists at
In order to establish whether Sodium Selenite is efficient or not in controlling
encephalomalacia, we decided to fallow several aspects of its efficiency insisting on the
capacity to intensify vitamin E activity.
The study developed in an ,,industrial type’’ holding for poultry breeding where
encephalomalacia envolves 5%.
The diagnosis was established considering clinical, paraclinical and morphopathological
investigations.The curative value of Sodium Selenit was searched in comparison with vitamin
E and AD E vitamines curative value.The investigations were carried-out on 5 lots of
chickens presenting incipient clinical manifestations of encephalomalacia considered
Analysing the results obtained we draw the conclusion that the curative value of Sodium
Selenit is reduced, being only 11,5%.
Sodium Selenit has the capacity to intensify the activity of vitamin E and AD E vitamines; its
curative value is negligible when it is used by itself.

Diet and diet-related diseases in captive short-tailed leaf-nosed bats (Carollia perspicillata)

A. de Boer1, S. van Hall1, J.Govers2*, P.Veenvliet1 and T.R. Huisman1*
1 Van Hall Institute (Dept. of Animal Management, Postbus 1528, 8901 BV Leeuwarden,
2 Artis Zoo, Postbus 20164, 1000 HD Amsterdam
* Contact persons

The short-tailed leaf-nosed bat (Carollia perspicillata) is a small frugivorous bat whose home
range stretches from southern Mexico to north eastern Brazil. It is also found on some of the
Caribbean islands. In 1995 a small colony of approximately 50 individuals was established in
Artis Zoo. Although there was reproductive success in this colony, mortality prevented the
population from growing. Post mortem results from the Department of Veterinary Pathology
of Utrecht University revealed insufficient calcification in the bones. Therefore the calcium
content of the diet was increased. This seemed to be successful but a new problem occurred;
post mortem examinations conducted after the diet change showed iron accumulation in liver
cells. Since the main health problems seemed to be diet related, a study into the captive
nutrition of Carollia perspicillata was started.
The nutritional content of the existing Artis diet was calculated with Zootritionä dietary
management software. At the same time, samples from the diet were analysed for crude
protein, crude fat, crude fibre, calcium and phosphorous in a certified laboratory. The iron
content of the diet was also analysed. To obtain reference values, an extensive survey was
conducted among other zoos with these specific bats. In addition, literature on in-situ
nutrition of Carollia perspicillata and nutrition of specialised frugivorous species was
Results demonstrated a high iron content in the Artis diet. Data from Zootritionä calculated
an iron content of 139mg/kg dry matter. The laboratory results showed an even higher
content of 177-mg/kg dry matter. Both figures are high above the recommended values
proposed by Schoemaker and Beynen (2001) in their study on the diet composition of
commercial diets for the highly frugivorous mynah birds (Gracula spp.). However the most
important observation in this study was the fact that calcium and mineral supplements
together with concentrates contributed more than 80 % to the total iron content of the diet in
Artis.Similar results were found at other zoos that contributed to the survey.
Based on these finding, is it is essential to check carefully the potential iron contribution of
supplements and concentrates in diets for frugivorous animals. In this particular case the
supposedly problem-solving calcium supplement caused a new diet related problem.