Biomedical subjects

A C Beynen

Publications and source records attributed to A C Beynen.

At least 19 recordsLinked to original sources

PubMed2007

The influence of dietary linoleic and alpha-linolenic acid on body composition and the activities of key enzymes of hepatic lipogenesis and fatty acid oxidation in mice.

We have recently suggested that feeding the C18 polyunsaturated fatty acid, alpha-linolenic acid (ALA), instead of linoleic acid (LA) reduced body fat in mice. However, the difference in body fat did not reach statistical significance, which prompted us to carry out this study using more animals and diets with higher contents of ALA and LA so that the contrast would be greater. The diets contained either 12% (w/w) LA and 3% ALA or 12% ALA and 4% LA. A low-fat diet was used as control. The diets were fed for 35 days. The proportion of body fat was not influenced by the type of dietary fatty acid. Plasma total cholesterol and phospholipids were significantly lower in ALA-fed mice than in mice fed LA. Activities of enzymes in the fatty acid oxidation pathway were significantly raised by these two diets when compared with the control diet. alpha-Linolenic acid vs. LA did not affect fatty acid oxidation enzymes. In mice fed the diet with LA activities of enzymes of de novo fatty acid synthesis were significantly decreased when compared with mice fed the control diet. alpha-Linolenic acid vs. LA feeding did not influence lipogenic enzymes. It is concluded that feeding mice for 35 days with diets either rich in LA or ALA did not significantly influence body composition.

Animals↗

PubMed2006

Mortality and growth performance of broilers given drinking water supplemented with chicken-specific probiotics.

For application in broiler production, we developed a multispecies (MSPB) and a chicken-specific (CSPB) probiotic preparation in fluid form. The MSPB contained different probiotic species of human origin, whereas the CSPB consisted of 7 Lactobacillus species isolated from the digestive tract of chickens. In a field trial with broilers, MSPB treatment resulted in a slight increase (by 1.84%) in broiler productivity based on an index taking into account daily weight gain, feed efficiency, and mortality. The CSPB treatment reduced mortality in 2 subsequent field trials and raised productivity by 2.94 and 8.70%. In a controlled trial with broilers showing a high index of productivity, probiotic treatment further raised productivity by 3.72%. Based on the present 4 studies in combination with 9 studies published earlier, it is suggested that with higher productivity rates of the broilers the effect of probiotics becomes smaller.

Animals↗

PubMed2005

Retrospective study of the survival of cats with acquired chronic renal insufficiency offered different commercial diets.

A retrospective study was carried out on the efficacy of seven commercial diets designed to be fed to cats with chronic renal failure. The median survival time of 175 cats that received conventional diets was seven months, whereas the median survival time of 146 cats given one of the seven diets was 16 months. The cats on the most effective of the diets had a median survival time of 23 months and those on the least effective diet had a median survival time of 12 months. The composition of the seven diets was comparable, except that the most effective diet had a particularly high content of eicosapentaenoic acid.

Animal Feed↗

PubMed2005

Intake of essential fatty acids by growing-finishing pigs kept on smallholdings in central Vietnam.

The intake of linoleic acid (LA) and alpha-linolenic acid (ALA) in relation to average daily weight gain (ADG) was studied in growing-finishing pigs kept on smallholdings in Central Vietnam. Groups of three piglets each were assigned randomly to 12 farms, where they were fed on local feedstuffs according to the farmer's choice but were given a restricted amount of dry matter according to a preset feeding regimen. On arrival at the farms, the pigs weighed 10.4 +/- 0.9 kg (mean +/- SD, n = 36) and at 130 days of age they weighed 45.4 +/- 9.6 kg. Dietary LA concentration ranged from 1.34 to 2.41 g/MJ metabolizable energy (ME) and ALA from 0.06 to 0.33 g/MJ ME. On a farm level, dietary LA and ALA concentrations were significantly correlated with their concentrations in adipose tissue, both correlation coefficients being 0.63. Dietary protein concentration and protein:energy ratio were significantly correlated with ADG, the correlation coefficients being 0.68 and 0.64. For individual piglets there were significant correlations between either LA or ALA in adipose tissue and ADG, the correlation coefficients being 0.37 and 0.45. Dietary protein concentration or protein:energy ratio was correlated with the dietary contents of LA and ALA. It is uncertain whether LA and ALA intake had a causal relationship with ADG. Since dietary LA levels were above the LA requirement, LA intake may not have limited growth. It is suggested tentatively that, through enhanced disease resistance, supplementation with ALA of the diets on the farms studied might have a positive influence on ADG.

Adipose Tissue↗

PubMed2005

Growth performance of lambs in Phangrang, Vietnam: effects of a dietary supplement containing prickly-pear cactus.

In Phanrang, Vietnam, sheep production is limited by the sparse availability of green roughage. Although prickly-pear cactus (Opuntia elator) is abundant in the area, it is not used. It was considered relevant therefore to test whether prickly-pear cactus could be used a component of feed supplements. With the use of the cactus and other local products--namely groundnut cake, fish sauce by-product, molasses, rice bran and cassava flour--two supplements were prepared. The level of cactus in the two supplements was 670 g/kg product (320 g/kg dry matter). The cactus was burned to remove the spines, chopped and sun-dried before use. The cactus preparation contained only 12 g crude protein/kg (68 g/ kg dry matter). The protein content of the two supplements was raised with either groundnut cake or fish sauce by-product. Sheep that were grazing during the day were offered either no supplement or one of the supplements when confined during the night. During a period of 3 months, non-supplemented control sheep gained 98 +/- 10.5 g/day (mean +/- SD, n=10). Sheep supplemented with cactus and groundnut gained 145 +/- 12.3 g/day, and those given cactus and fish sauce gained 130 +/- 11.7 g/day. It is concluded that prickly-pear cactus has potential as component of feed supplements for sheep.

Animal Feed↗

PubMed2005

Qualitative risk assessment of chronic renal failure development in healthy, female cats as based on the content of eicosapentaenoic acid in adipose tissue and that of arachidonic acid in plasma cholesteryl esters.

A study was carried out to assess the qualitative risk of development of chronic renal failure (CRF) in young healthy, female cats as based on the content of arachidonic acid (AA) in plasma cholesteryl esters (CE) and eicosapentaenoic acid (EPA) in adipose tissue. It has been suggested that the content of AA in CE should be <10% of total fatty acids (TFA) and of EPA in adipose tissue be >1.4% of TFA. Subcutaneous adipose tissue and blood samples were obtained from 48 female cats. There was a statistically significant correlation between linoleic acid content of adipose tissue and that of plasma CE. In all cats the EPA content of adipose tissue was lower than 1.4% of TFA and in 30 cats that of AA in plasma CE was higher than 10% of TFA. The EPA content of adipose tissue and the AA content of plasma CE are determined by the contents of these fatty acids in the diet. It is concluded that the fatty acid composition of cat foods should be determined and that, if deemed necessary, the ingredient composition should be altered so that the content of EPA is raised and that of AA is lowererd.

Adipose Tissue↗

PubMed2005

Cholate and deoxycholate counteract the calcium-induced lowering of fat digestion in rats.

The objective of the present experiment was to investigate whether deoxycholate and cholate would differ in their effectiveness of counteracting the inhibitory effect of calcium on fat digestibility in rats. Rats were fed one of four experimental diets, a diet low in calcium, high in calcium or high in calcium with either 0.5% sodium cholate or 0.5% sodium deoxycholate. Both deoxycholate and cholate supplementation of the high-calcium diet reduced feed intake and body-weight gain. Low-calcium intake increased fat digestibility. Supplemental bile acids partially counteracted the calcium-induced inhibition of fat digestion, cholate being more effective than deoxycholate. The outcome is explained by the suggestion that cholate is bound to the calcium phosphate sediment in the small intestinal lumen with less affinity than deoxycholate. As a result, more cholate than deoxycholate would be available to support the process of fat digestion. Rats fed cholate had higher liver and serum cholesterol concentrations than did the rats fed deoxycholate.

Animals↗

PubMed2005

Effect of sodium phytate supplementation on fat digestion and cholesterol metabolism in female rats.

The effects of sodium phytate supplementation on fat digestion and cholesterol metabolism were investigated in female rats. On the basis of an in vitro experiment showing that phytate raised the solubility of bile acids, it was predicted that phytate feeding would depress faecal bile acid excretion, raise apparent fat digestibility and elevate serum cholesterol concentrations. The experimental diets with or without sodium phytate were either cholesterol-free or cholesterol-rich and had a normal calcium concentration. Rats fed on the cholesterol-rich diet with sodium phytate showed enhanced faecal bile acid excretion, but there was no effect on fat digestibility. In rats fed the cholesterol-free diets, phytate did neither affect fat digestion nor bile acid excretion. Sodium phytate inclusion in the cholesterol-rich diet raised serum cholesterol concentrations, but reduced liver cholesterol concentration. Thus, the in vivo data do not agree with the in vitro observations. Both phytate and cholesterol feeding influenced mineral and trace element metabolism. Liver zinc concentrations were raised by phytate feeding. Cholesterol consumption reduced hepatic concentrations of copper, iron and zinc. Both phytate and cholesterol feeding reduced the apparent absorption of calcium, magnesium and phosphorus.

Animal Feed↗

PubMed2005

Plasma lipids and fatty acid composition in parrots in relation to the intake of alpha-linolenic acid from two feed mixtures.

The main objective of this study was to find out whether the content of alpha-linolenic acid (ALA) in plasma cholesteryl-esters (CE) or triglycerides (TG) in parrots might serve as an index of ALA intake. The intake of ALA might be a risk factor for atherosclerosis, but on the basis of the fatty acid composition of seed mixtures the intake is difficult to assess due to selective eating of seeds. Parrots were fed two seed mixtures that differed in ALA content according to a cross over design. The macronutrient composition of the diets supplied differed from that of the diets consumed. The diets consumed had higher levels of dry matter, crude protein, crude fat and energy, and lower levels of crude fibre and crude ash. The ALA content, expressed as g/kg diet, was similar for the diet supplied and that consumed, irrespective of the type of diet. The diets had no systematic effect on plasma lipid concentrations. There were marked differences in plasma cholesterol concentrations between parrot species. When the diet with the low ALA content was fed (0.8% ALA of total fatty acids consumed, 1.1 g ALA/kg of diet consumed), the plasma CE and TG did not contain detectable ALA amounts. When the diet with the high ALA content was fed (4.2% ALA of total fatty acids consumed, 6.1 g ALA/kg of diet consumed), the plasma CE and TG contained about 1% ALA of total fatty acids. It is suggested that the content of ALA in plasma CE and TG might be used as an indicator of ALA intake.

Animal Feed↗

PubMed2005

Health and growth of veal calves fed milk replacers with or without probiotics.

Four experiments with 1-wk-old veal calves were conducted to assess the influence of probiotics on growth and health indicators. In experiments 1 and 2, the liquid probiotic supplements were administered daily from experimental d 1 to 15. The treatment period in experiments 3 and 4 was extended to 56 d. The probiotics used were a multispecies probiotic (MSPB) containing different probiotic species of human origin, or a calf-specific probiotic (CSPB) containing 6 Lactobacillus species isolated from calf feces and selected on the basis of a combination of characteristics. When the data for the 4 experiments were pooled, the probiotics enhanced growth rate during the first 2 wk. During the 8-wk experimental period, average daily gain and feed efficiency were significantly improved in the probiotic-treated groups. The MSPB-induced increase in weight gain was greater when the control calves were considered less healthy based on a health score (an index of diarrhea and therapeutic treatments). Probiotic treatment tended to diminish mortality. The CSPB treatment reduced the incidence of diarrhea and the fecal counts of coliforms. When therapeutic treatment was intensive in the control calves, the ingestion of probiotics reduced the percentage of calves that required therapy and the amount of treatments needed against digestive or respiratory diseases. There was no clear difference in the efficiency of the MSPB and CSPB preparations. Further research is necessary to identify underlying mechanisms and to evaluate the potential of probiotics to improve respiratory health in veal calf production.

Animals↗

PubMed2004

Monostrain, multistrain and multispecies probiotics--A comparison of functionality and efficacy.

This literature review was carried out to make a comparison of functionality and efficacy between monostrain, multistrain and multispecies probiotics. A monostrain probiotic is defined as containing one strain of a certain species and consequently multistrain probiotics contain more than one strain of the same species or, at least of the same genus. Arbitrarily, the term multispecies probiotics is used for preparations containing strains that belong to one or preferentially more genera. Multispecies probiotics were superior in treating antibiotic-associated diarrhea in children. Growth performance and particularly mortality in broilers could be improved with multistrain probiotics. Mice were better protected against S. Typhimurium infection with a multistrain probiotic. A multispecies probiotic provided the best clearance of E. coli O157:H7 from lambs. Rats challenged with S. Enteritidis showed best post-challenge weight gains when treated with a multispecies probiotic. Possible mechanisms underlying the enhanced effects of probiotic mixtures are discussed. It is also emphasized that strains used in multistrain and multispecies probiotics should be compatible or, preferably, synergistic. The design and use of multistrain and multispecies probiotics should be encouraged.

Animals↗

PubMed2004

[Comparative analysis of commercial renal diets for cats, with emphasis on their fatty acid composition].

The objective of this study was to compare renal diets for cats that are commercially available in The Netherlands. The diets were analysed and their composition compared with a guideline proposed by the authors. Special attention was paid to the fatty acid composition of the diets and the role of fatty acids in the progression of chronic renal failure. On the basis of a total score for nutrient levels relative to the guideline recommendations, the diets were ranked as to expected efficacy.

Animal Feed↗

PubMed2004

Changes in the feed intake, pH and osmolality of rumen fluid, and the position of the abomasum of eight dairy cows during a diet-induced left displacement of the abomasum.

During the last six weeks of the dry period, eight Holstein-Friesian cows were fed a restricted amount of grass silage; after calving, a mixture of maize silage and concentrates was offered in a feeding regimen designed to induce a displacement of the abomasum. In the first month after calving, the cows were monitored for the following variables: feed intake and composition, milk production, the position of the abomasum, and the pH and osmolality of the rumen contents. In five of the eight cows, a left displacement of the abomasum occurred between four and 21 days after calving in the absence of other diseases. The displacement was temporary, lasting between five and 36 consecutive hours and one or two days in two of the cows (floaters), and for three or more days in the other three. Before these three cows developed the displacement, their abomasum was 4.3 to 7.9 cm higher, its contents had a higher mean osmolality (+19.2 mosmol/kg), and the ratio of roughage to concentrates in their feed was lower (-0.87) than in the three cows that did not develop clinical signs of a displaced abomasum. There were no significant differences in these variables between the floaters and the healthy cows.

Abomasum↗

PubMed2004

Feeding of spinach or sweet-potato leaves and growth performance of growing pigs kept on smallholder farms in Central Vietnam.

We investigated whether the addition of either spinach or sweet-potato leaves to the diet of growing pigs, kept in small holdings in Central Vietnam, would improve growth performance. A control diet was formulated and mixed with each of the vegetables to a final concentration of 15% of the total dietary dry matter. The diets were fed to the pigs from 70 to 100 days of age on six different smallholder farms in Central Vietnam. There were three animals per treatment group per farm and biopsies of adipose tissue were analysed for their contents of alpha-linolenic, eicosapentaenoic and docosahexaenoic acids. The diets without and with vegetables contained on average 0.14 and 0.32 g alpha-linolenic acid per MJ metabolizable energy. The relative percentage of alpha-linolenic acid in adipose tissue was raised by the intake of the vegetables. Eicosapentaenoic acid was not detectable in adipose tissue and the level of docosahexaenoic acid was unchanged. There was a significant stimulatory impact of the intake of either spinach or sweet-potato leaves on growth performance of the growing pigs. It is suggested that an adipose tissue content of alpha-linolenic acid less than 1% of total fatty acids does not allow maximum growth in growing pigs.

Adipose Tissue↗

PubMed2004

The relationships between potassium intakes, transmural potential difference of the rumen epithelium and magnesium absorption in wethers.

In vitro studies with isolated sheep rumen epithelium have shown that an increase in the lumen K concentration induces an increase in the transmural potential difference across the rumen epithelium (serosal side: positive), which is associated with a decrease in Mg transport. However, at lumen K concentrations >80 mmol/l, Mg transport across the epithelium became independent of the lumen K concentration. The present study was carried out to determine whether this observation also occurs in vivo. Four ruminally fistulated wethers were fed four rations supplemented with KHCO3 (15.7, 37.6, 59.4 or 77.4 g K/kg DM) in a 4 x 4 Latin square design. Increased K intakes significantly increased the rumen K concentration. For all data combined, Mg absorption expressed as % intake was negatively correlated with the rumen K concentration. However, apparent Mg absorption either expressed in absolute terms (g/d) or as % intake was not significantly affected when the dietary K concentration was increased from 59.4 to 77.4 g/kg DM. Rumen K concentration was inversely correlated with the transmural potential difference (blood side: positive) (Pearson's r -0.709; R(2)adj 0.468, P=0.002, n 16). It is concluded that in wethers apparent Mg absorption becomes independent of the dietary K concentration when the K concentration is >60 g/kg DM or equivalent to a postprandial rumen K concentration of about 125 mmol/l.

Absorption↗

PubMed2004

Lowering dietary phosphorus concentrations reduces kidney calcification, but does not adversely affect growth, mineral metabolism, and bone development in growing rabbits.

New Zealand White rabbits were used to investigate the influence of increasing dietary P concentrations on growth performance, mineral balance, kidney calcification and bone development. The minimum dietary P requirement of 0.22 % (National Research Council) is usually exceeded in commercial natural-ingredient chows, leading to undesirable kidney calcifications. In order to study the optimal dietary P level, rabbits were fed semi-purified diets with four different P levels (0.1, 0.2, 0.4, and 0.8 %; w/w) at a constant dietary Ca concentration (0.5 %) during an 8-week period. Body weight and growth were not influenced by the dietary P level. During two periods (days 20-23 and 48-51), faeces and urine were collected quantitatively for the analysis of Ca, Mg and P and balances were calculated. Increased dietary P intake caused increased urinary and faecal P excretion and P apparent absorption and retention. Faecal Ca excretion increased with higher dietary P levels, whereas urinary Ca excretion reacted inversely. The apparent absorption of Ca became reduced at higher dietary P concentrations, but Ca retention was unchanged. The response of Mg was in a similar direction to that of the Ca balance. Kidney mineral content increased with higher dietary P levels, indicating the presence of calcified deposits. Nephrocalcinosis became more severe in kidney cortex and medulla at increasing dietary P levels, as was confirmed by histological analysis. Femur bone length was not differentially influenced by dietary P. Bone density (g/cm(3)) of the femur diaphysis became significantly lower at the 0.8 % dietary P level as compared with the 0.2 % P group only. The bone Mg content was significantly increased on the 0.8 % P diet, both in the diaphysis and epiphysis. Plasma P concentration increased and plasma Ca decreased with higher dietary P levels, whereas plasma Mg levels were unaffected. The present study shows that the current recommended minimum dietary P level of 0.2 % for rabbits, as advised by the National Research Council in 1977, leads to a normal growth and bone development, but also causes some degree of kidney calcifications at a dietary Ca level of 0.5 %. As the dietary P level of 0.1 % virtually prevented kidney calcification and at the same time did not give evidence for any deleterious effects on growth and bone development, this indicates that the current recommended dietary P level for rabbits should be regarded as a maximum advisable concentration, and that a lower P level may be more optimal.

Animals↗

PubMed2004

The effect of six different C18 fatty acids on body fat and energy metabolism in mice.

We studied the effects of five high-fat semi-purified diets varying at a 4% (w/w) level in either stearic, oleic, linoleic, alpha-linolenic, or gamma-linolenic acid on body fat and energy metabolism in BALB/c mice. A diet containing caprylic, capric, lauric, and myristic acid was used as a reference diet and a diet with 4% conjugated linoleic acid (CLA) was used as a positive control as it is known to effectively lower body fat in mice. The diets were fed for 35 d. Body fat was significantly lower in the CLA group than in the other groups but was not significantly different among the non-CLA groups. Among the non-CLA groups, the linoleic acid group tended to have the highest and the alpha-linolenic acid group the lowest proportion of body fat. In energy-balance studies, the percentage of energy intake that was stored in the body was significantly lower in the CLA group compared with the other dietary groups. The percentage of energy intake eliminated in excreta was highest in the stearic acid group followed by the gamma-linolenic acid group. These results were reflected in apparent fat digestibility, which was lowest in the stearic acid group. The percentage of energy intake expended as heat was highest in the CLA-fed mice. The results of the present study suggest that body fat and energy accretion in mice fed diets containing different C18 fatty acids is by far the lowest with CLA and that linoleic acid produced the highest fat intake and energy accretion.

Adipose Tissue↗

PubMed2004

Atherosclerosis in parrots. A review.

Atherosclerosis is a common disease in parrots. The disease is found in all common parrot species, but especially in African Grey parrots and Amazons. It is a disease of older birds that is seen in both males and females. The most common sign is sudden death, but clinical symptoms that can be found include dyspnea, lethargy and nervous signs, such as paresis and collapses. Because the clinical signs are seldomly seen, it is difficult to diagnose atherosclerosis and therefore it is mostly an unexpected finding at necropsy. Age and species are determinants of atherosclerosis in parrots. Suggested risk factors include an elevated plasma cholesterol level, diet composition, social stress and inactivity, but research is needed to confirm this.

Animal Feed↗