Biomedical subjects

W Drochner

Publications and source records attributed to W Drochner.

At least 37 records · Page 2Linked to original sources

PubMed2001

Influence of hay particle size at different concentrate and feeding levels on digestive processes and feed intake in ruminants. 2. Passage, digestibility and feed intake.

In order to study the main effects of particle size, three ruminally fistulated cows (550 to 580 kg BW) were fed a constant low concentrate level (3.56 kg DM/d, 20% of total DMI) and a fibre-rich hay (approximately 60% NDF in DM) in long (28.7 mm), chopped (9.2 mm) and fine ground (2.9 mm) form in a 3 x 3 Latin square design. In another three factorial experiment with 8 wethers (4 animals were ruminally fistulated, mean BW = 68 kg) the main effects and interactions of the above mentioned hay particle sizes at two concentrate levels (10.4 to 13.3% and 29.5 to 40.1% of DMI, resp.) and two intake levels (restricted and ad libitum) were investigated. In comparison to long hay (28.7 mm), feeding of chopped hay (9.2 mm) at low concentrate levels, increased not only the hay intake (7% in dairy cows and 13% in sheep) but also the intake of digestible organic matter (12% in dairy cows and 32% in sheep), due to an increase in the apparent digestibility of OM by 3.8% in dairy cows and 8.2% in sheep. Ad libitum feeding of fine ground hay in combination with low concentrate amount in the ration increased the passage rate in the hindgut and consequently the hay intake, but not the intake of DOM, due to a significant depression of digestibility, especially of fibre fractions (4 to 7% in dairy cows and 4.5 to 14% in sheep), in comparison to 28.7 and 9.2 mm hay particle sizes. The digestibility decreased significantly with restricted feeding of fine ground hay in sheep only in comparison to 9.2 mm particle size. A threefold increase of concentrate amount leveled out all effects of the particle size reduction. The effect of particle size was more pronounced in sheep than in dairy cows.

Animal Feed↗

PubMed2001

Research note: a method for studying local differences in ruminal fermentation in dairy cattle.

A method was developed for studying local differences in ruminal fermentation. The developed sampler consisted of an acrylic glass container (460 cm3) with an aperture for digesta sampling, which could be opened and closed by the scaled "T" rod. The scale was a reference for defined rumen layers: top, middle, 5 to 10 cm and 25 to 35 cm beneath the top of particles mat, respectively, and bottom 5 to 10 cm above the rumen floor. The repeatability of the method was proved in two rumen cannulated cows. Particle/fluid ratio, pH and sample amount were measured 2 to 2 1/2 h after morning feeding in four replicates each day (over 5 days), rumen layer and animal. No significant differences between replicates were observed. The coefficients of variation (CV) of the particle/fluid ratio varied between 8.7% and 13.6%. Top layer had higher CV than middle and bottom layer. CV of pH ranged between 0.59% and 1.27%. The developed method of sampling showed satisfactory repeatability for investigation of digesta properties and fermentation in different rumen layers.

Animals↗

PubMed2000

Acceptance and digestibility of some selected browse feeds with varying tannin content as supplements in sheep nutrition in west Africa.

In 1994 and 1995 leaves from 10 selected West African trees and shrubs with varying tannin content were tested to determine their suitability as an alternative and supplementary browse feed for West African dwarf sheep to improve productivity in small-scale holdings in Benin. Dry matter intake per kg metabolic body weight (DM g/kg W0.75) varied between the different browse feeds and between the different trials and ranged from zero (Leucaena leucocephala) up to 26.7 DM g/kg W0.75 (Margaritaria discoidea). The digestibility of the organic matter varied between 58.9% (L. leucocephala) and 68.2% (Mallotus oppositifolius). Agelaea obliqua showed the highest levels of total phenols (10.2%), tannin phenols (8.8%) and extractable condensed tannins (8.0%). Leaves from various browse feeds are a good and protein-rich supplementary fodder in addition to the grass Panicum maximum. However, feeding of A. obliqua and Cnestis ferruginea should be avoided due to toxic components.

Animal Feed↗

PubMed2000

The chemical composition of Phyllanthus discoideus and its effect on the ruminal ammonia and volatile fatty acid concentration when fed to west African dwarf sheep.

The feeding value of Phyllanthus discoideus (also called Margaritaria discoidea) leaves was evaluated using eight two-year-old West African Dwarf sheep fed natural grass hay. Four of the animals were fistulated ruminally and used for ammonia and volatile fatty acid determination in the fluid. Dried leaves of Phyllanthus discoideus were offered at two levels (25% and 50% of DMI, diets D25% and D50%, respectively) as supplements to the basal hay diet. The CP content of the control, D25% and D50% diets were 11.5, 12.6 and 13.6%, respectively, and their digestible energy amounted to 58.2, 61.1 and 56.9%, respectively. Rumen liquor was sampled one hour before and one, three and five hours after the morning feeding. Sheep fed the control diet had a higher ruminal ammonia concentration than those fed diet D25%. Similarly, ruminal ammonia concentration was higher in sheep fed the control diet than those fed the diet D50%. Five hours after feeding the ruminal ammonia concentration was significantly lower than one hour after feeding. The VFA concentrations in rumen fluid of sheep fed the control diet was inferior to those fed diets D25% and D50%. Sheep fed diet D50% showed significantly higher VFA concentrations than those fed diet D25%. Digestibility of organic matter and digestible energy did not show any significant difference. However, a marginal increase in organic matter digestibility of 3.5% was observed in diet D25% compared with the control diet. There was no significant difference in the N-digestibility in sheep fed the control, D25% and D50% diets. Nevertheless, a marginal improvement in N-digestibility (1.5%) and N-retention (2.7%) was observed with the highest level of Phyllanthus discoideus (D50%). In conclusion, Phyllanthus discoideus appears as a particularly valuable feedstuff because it contains low levels of condensed tannins (12.8 g/kg), high CP content (156 g/kg) and a relatively high GE content (19.3 kJ/g DM). Although the improvement in N-digestibility and N-retention were only marginal the feeding of Phyllanthus discoideus could be justified under extreme shortage of feed resources during dry season. It should also be mentioned that a much more pronounced effect by supplementation with Phyllanthus discoideus could be expected when poor quality grass hay prevalent in West Africa during the dry season is fed. Phyllanthus discoideus could serve as a supplement to poor quality grass at 25% to 50% of supplementation.

Ammonia↗

PubMed1999

Influence of microbial phytase and dietary calcium on the accumulation of lead in different organs of pigs.

The objective of this study was to investigate the influence of microbial phytase and calcium supplementation to diets for growing pigs on the retention of lead in the kidney, liver, muscle, brain, and bone (phalanx 1). The experiments were carried out with barrows over the body weight range from 17 to 50 kg. The average lead concentration of the diets was 1.45 mg/kg dry matter. Diets were prepared with or without a supplement of 800 units of microbial phytase. The calcium concentration in the diets was 6.53 or 13.4 g/kg dry matter. The addition of microbial phytase showed an increase of lead concentration in bone. By increasing the calcium concentration to 13.4 g/kg dry matter, it was possible to avoid the phytase-induced increase of lead retention in bone.

6-Phytase↗

PubMed1999

A survey of Fusarium toxins in cereal-based foods marketed in an area of southwest Germany.

A total of 237 commercially available samples of cereal-based foods including bread and related products, noodles, breakfast cereals, baby and infant foods, rice and other foods were randomly collected in southwest Germany during the first six months of 1998. The trichothecenes deoxynivalenol (DON), 3- and 15-acetyl-deoxynivalenol (3-,15-ADON), nivalenol (NIV), fusarenon-X (FUS-X), T-2 toxin (T-2) and HT-2 toxin (HT-2) were determined by gas chromatography/mass spectrometry following clean-up by a two stage solid-phase extraction. Detection limits ranged between 2 and 12 micrograms/kg. Based on all samples, the incidence of DON, HT-2, T-2, 3-ADON, 15-ADON, and NIV was at 71, 18, 4, 4, 4 and 2%, respectively; the average contents in positive samples were at 103, 16, 14, 17, 24 and 109 micrograms/kg, respectively. Fus-X was not detected in any sample. A lower (P < 0.05) DON content was found in baby and infant foods as well as in cookies and cakes compared to bread. Overall, based on the incidence and level of all six toxins, the degree of contamination was lowest in baby and infant foods. Foods produced from either white or whole grain flour did not differ (P > 0.05) with regard to the incidence and level of DON. In foods produced from cereals of organic production both the incidence and median content of DON was lower compared to conventional production. Zearalenone, alpha- and beta-zearalenol were determined by high performance liquid chromatography in 20 selected samples, mostly baby and infant foods. These toxins were not present in excess of the detection limit in any sample.

Bread↗

PubMed1999

[Effect of hay particle size at different concentrations and feeding levels on digestive processes and feed intake in ruminants. 1. Chewing activity and fermentation in the rumen].

In order to study the main effects of particle size three ruminally fistulated cows were fed a hay rich in fibre in long (28.7 mm), chopped (9.2 mm) and ground (2.9 mm) form in a 3 x 3 Latin square design. In another three factorial experiment with 8 wethers (4 animals were ruminally fistulated) the main effects and interactions of the above mentioned hay particle size at two concentrate levels (10.4 to 13.3 and 29.5 to 40.1% in the ration) and at two feeding levels (restricted and ad libitum) were investigated. There was no effect of chopped hay (9.2 mm) on chewing activity, whereas ground hay (2.9 mm) reduced rumination time (52% in sheep and 36% in dairy cows) and chewing expense (time/unit of DM or NDF intake). These effects were more pronounced at high concentrate intake. Sheep increased feed intake more through reduction of rumination expense than through the extension of rumination time. pH-value, concentration of bicarbonate and C2:C3-ratio indicate favourable fermentation conditions in long (28.7 mm) and chopped hay (9.2 mm), whereas a negative influence of ground hay (2.9 mm) or ruminal fermentation could be observed.

Animal Feed↗

PubMed1999

[Rumen fermentation and digestibility of nutrients studied by the addition of Ca soaps of palm oil fatty acids and their analogous fatty acids in the sheep model].

The ruminally fistulated sheep was used as a model to study the effects of fat supplementation (Ca-soaps and free long chain fatty acids from palm oil) on rumen physiology and digestibility of the nutrients. The animals were fed with a typical ration of hay and concentrate supplying nutrients according to maintenance levels. The following results should be pointed out: The addition of free fatty acids and their Ca-soaps induced a retarded recovery of postprandially decreased pH-values in ruminal fluid. This retardation was more pronounced after addition of free long chain fatty acids than with their Ca-soap-analogous acids. Compared to the control, the concentration of short chain fatty acids was depressed by fat addition in the period 2 hours after feed intake. The release of ammonia in the first period after feed intake was reduced by fat addition. A lack of synchronity could be observed in this post-prandial period in ruminal fluid between concentration of short chain fatty acids and ammonia. This effect was most obvious with supplementation of unprotected fatty acids. This might be one reason for the better tolerance of Ca soaps from palm oil fatty acids. Formation of hydrides, branched chains and transforms proceeds more effectively with free fatty acids than with their analogous forms of Ca-soaps. The well-known effect of depression of digestibility of nutrients due to fat supplementation was--under present conditions--quite low. This might be different in lactating dairy cows with higher levels of feed intake. With high feed intake, passage time is reduced. This will affect digestibility and interactions with fat supplementation.

Animals↗

PubMed1998

Determination of eight trichothecenes by gas chromatography-mass spectrometry after sample clean-up by a two-stage solid-phase extraction.

A method is described for the determination of eight trichothecenes of type A and B in a variety of complex matrices including heavily moulded and pigmented cereals, whole cereal ears, cereal-based foods, mixed feeds and faeces from swine. Trichothecenes were determined as their trifluoroacetyl derivatives by gas chromatography with ion-trap mass spectrometry detection operating in chemical ionization mode. Isobutane was chosen as reactant gas and optimum parameters of measurement were determined. For sample preparation a clean-up procedure was developed using a combination of Florisil and cation-exchange cartridges for solid-phase extraction. Limits of detection and quantification as well as recoveries are described.

Animals↗

PubMed1996

Prediction of the net energy content of raw materials and compound feeds for ruminants by different laboratory methods.

In this study three different laboratory procedures were compared as predictors of net energy content of raw materials and compound feeds for ruminants. Laboratory measurements included an enzymatic technique (pepsin-cellulase method) and a rumen fluid technique (Hohenheim gas test). An estimate based on crude nutrients only was also tested. A total of 98 feed samples with known in vivo digestibility were available. By multivariate regression analysis equations for the prediction of the net energy content were calculated. The results suggest that in case of compound feeds for dairy the cellulase technique and the gas test are suitable in vitro techniques. With both procedures the relationships between energy contents estimated in vitro and energy contents measured in vivo showed residual errors of less than 4 percent. However for the evaluation of raw materials the gas test was superior. Compared to the cellulase technique the risk of extreme under- or overestimations is apparently reduced and this was found to be the case for own prediction equations as well as equations from literature. Crude nutrients proved to be very poor predictors for all feed samples.

Animal Feed↗

PubMed1995

[Effect of ethoxyquin on the utilization of selenium in growing pigs].

In a 2 x 3 factorial arrangement with 30 male castrates (German Landrace; 13.7 +/- 1.7 kg b.w.), after a 2 week feeding period with a maize/torula yeast basal diet poor in selenium and without vitamin E supplementation, the effect of two ethoxiquin concentrations (0 and 150 mg/kg) und 3 selenium concentrations (0.075, 0.10 and 0.125 mg/kg) on growth, the activity of the Se dependent GSH-Px in the erythrocytes and the Se concentrations in liver, kidney, heart and diaphragm was measured after 4 weeks on the experimental diets. Under the experimental conditions chosen ethoxiquin had no effect of any of the parameters studied. Selenium supplementation significantly increased the enzyme activity and the Se concentrations in the organs and tissues analyzed.

Aging↗

PubMed1994

[The effect of a different protein and fiber intake on the ileal flow of endogenous protein in 15N-labeled swine].

The endogenous N in ileal digesta of pigs was estimated in two experimental variants. In variant 1 the crud protein content of a wheat-maize-fish meal diet was 18% and the crude fibre content was 1.9% (diet 1) and 2.7% resp. (diet 2). In variant 2 the crude protein content was 12.5% (wheat-maize-diet) and the crude fibre content was 4.1% (diet 3) and 5.5% resp. (diet 4). The higher crude fibre content of the diets 2-4 was provided by means of a supplementation with partially hydroyzed straw meal plus pectin (2:1 w/w). Four miniature pigs with an average initial body weight of 29 kg, were fitted with a ileocaecal re-entrant cannula and received each one of the four different diets. 15NH4Cl, added to the diets, was given for 5 days (150 mg 15N-excess/kg0.75 BW*d) to label the animals with 15N. Ileal digesta, urine and faeces were collected over 24 hours on 8th, 10th and 12th day after the first intake of 15N. The 15N-excess of urine N was used as the comparative measure of 15N-excess of endogenous protein. The amount of nitrogen collected in ileal digesta was in order of the diets 1-4 = 258, 299, 200 and 224 mg/kg0.75 BW*d and of these amounts were 50.1, 52.1, 56.1 and 50.4% of endogenous origin. This were corresponding, after conversion into crude protein to 9.1, 11.2, 10.8 and 11.0 g/100 g crude protein intake or 16.9, 19.7, 13.8 and 13.4 g/kg dry matter intake, respectively. The bacterial N-flow were in order the diets 1-4 = 94.0; 72.7; 55.8 and 52.6 mg/kg0.75 BW*d and 73, 46, 50 and 47% resp. of the endogenous N or 36, 24, 28 and 24% of the ileal total N. The results show, that the absolute amounts of endogenous and bacterial N at the terminal ileum were significantly increased by a higher crude protein content of the diet. The percentage of endogenous and bacterial N on the total N of the ileal digesta was not affected neither by the crude protein content of the diets nor by the fibre supplements.

Animal Feed↗

PubMed1994

[PCB concentration in hair, blood, tissues and secretions of chronically exposed dairy cows, fattening bulls and calves].

Fattening bulls (n = 8) and cows (n = 10) affected chronically with PCB were kept in barns on PCB-free feeding (silage, straw, concentrates). The cows were dried off. The kinetics of PCB-concentrations in hair, blood and feces were examined. Fattening bulls (mean 460 kg bw, german black and white and interbreeding german black and white and Simmental) with low (320 g) and medium (730 g) daily weight gain for a period of 5 months and 3 bulls with medium (640 g) weight gain within 18 months were examined. A drying off period of 3-5 months was recorded for the cows. The distribution of PCB in the carcass of some animals was registered in addition. The following results are to be emphasized: Reduction of PCB in the studied substrates in the fattening bulls depends on a high degree on daily weight gain. This is important in order to calculate biological half life times of PCB. By standardized weight gain of 10 kg in bulls, fed PCB-free diets for a 5 months period, a reduction of PCB-concentrations from 1 to 3% was found (hair and feces: 1%, blood 3%). Within a period of 18 months and with higher weights, in the examined substrates (blood, hair, feces) mean declines of the PCB-concentrations of 2% were found. On knowledge so far this value is an essential point to estimate biological half life times, because metabolic PCB-elimination is negligible.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Digestion of carbohydrates in the pig.

A review of carbohydrate digestion in the pig is given. The cascade of digestion in the mouth, stomach, small and large intestine is described. Principles of enzymatic and fermentative digestion according to new results with fistulated animals are discussed. The efficacy and quality of fermentation in the large intestine depending on level and quality of carbohydrates in the diet are demonstrated. Some aspects of energetical efficacy of hindgut digestion are discussed. Dietetic effects of carbohydrates are described.

Animals↗

PubMed1992

[PCB concentrations in hair, blood, tissues and secretions of chronically-exposed dairy cows, fattening bulls and calves. 1. Course and relation of some polychlorinated biphenyls in hair, milk and tissues in exposed nursing cows and conventionally raised dairy cows].

20 cows contaminated chronically with PCB were kept as nurse cows or in a tie-stall. The contamination in different substrates (hair, milk, blood, feces) was examined for a period up to 8 months. The distribution of PCB in the carcass of some animals was registered in addition. The system of keeping nurse cows turned out to be useful in order to overcome a contamination situation. Drying off gravid animals in the first step helps solving problems of handling contaminated milk. With low contaminated animals a short dry off period is sufficient, so that the milk--after calving--is marketable (report II, in preparation). In case of nurse cows with two calves post partum a continuous decline of PCB-concentrations in the milk can be observed. With biological half life periods of 2-4 months, milk with PCB 153-concentrations of 0.15-0.20 mg/kg fat will be marketable within this period. Cows milked by milking-machines show a decline of PCB in the milk similar to nurse cows. Two animals had a limited increase p.p., probably caused by mobilization of fat in the high lactation stage. Over longer periods, the biological half-life-periods were comparable to nursing cows. Hair is easy to sample and store; it is useful as a diagnostic substrate beside the milk in order to estimate the degree of contamination in individual animals. The ratio of PCB-concentrations between perirenal fat and hair is 1:0.95 (s = +/-0.192); the ratio of PCB-concentrations between perirenal fat and milk is 1:0.77 (s = +/- 0.122).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1991

[Ergot in feed--the clarification of possible ergot-related infirmity cases].

Practicing veterinarians should realize that the symptoms of ergot intoxication may differ markedly. Gangrenous alterations (ears, feet, tail) as well as convulsive signs (excitability) are described as typical symptoms of ergotism. It is noteworthy that inadequate development of the udder and lactation failure may also be related to ergot contaminated diets. Ergot contamination of diets is caused by grain infection with Claviceps purpurea and sometimes by infection of grass and weed (in grain). The frequency of ergot contamination is high in rye, triticale and wheat and varies in relation to region, climatic conditions and kind of wheat. For diagnosis of ergot contamination a thorough visual inspection of the used diet is to be recommended. Due to the variation of ergots (infected grain, infected weed) it is difficult to determine the contamination in prepared feed mixtures. The anamnestic procedure, method of visual feed inspection as well as a chromatographic method for detection of ergot alkaloids in feed samples are described to facilitate the detection of possible ergot related cases.

Animal Feed↗

PubMed1990

[Intestinal syndrome of absent fermentation in swine after liquid feeding of easily-fermentable components].

Intestinal dysfermentation with diarrhea, tympania and accidental cases of sudden death in the pig after liquid feeding of components highly fermentable. 6 cases of the veterinary feeding advisement of the Institute of animal nutrition are presented, which can be described with the complex of symptoms: diarrhea, bloat, sudden death. These are related to feeding technique, feed composition and hygienic quality of the feed. All techniques of feeding, causing abundant feed intake and thus an exceeding of the digestive capacity of the gut are a predisposition for fermentative disturbances. A high level of feed hygiene can only be maintained in liquid feeding systems by high efforts concerning cleaning. A reduced hygienic feed quality in all present cases was apparent. All rations had a high content of easily fermentable components (sugar, partially enzymatically predigested starch). The clinical symptoms correspond to the well known "whey-syndrome". They are however not strictly correlated to rations with high whey contents. The prophylactic procedure especially concerns the improvement of the hygienic feed quality, the feeding technique and the addition of acids.

Animal Feed↗

PubMed1990

[Clinical effects of an extreme Ca overdose in feed for growing piglets].

In a piggery (approx. 60 sows) nearly all the weaned piglets (about 150) showed signs of poor development, reduced feed intake, increased water consumption, markedly dry and hard faeces, urine drinking, navel suckling and drowsiness over 6-8 weeks. In blood samples of 4 affected piglets a significant hypercalcaemia (values greater than 20 mg/dl)--combined with an at times marked hypophosphataemia--was measured. In the diet offered, a Ca content of 56.2 g/kg was estimated. An intoxication due to ochratoxin or due to excessive levels of quinoxaline or vitamin D was excluded by toxicological investigations of the diet. Contamination by Datura stramonium was also ruled out.

Animal Feed↗