The energetic utilization of rations with dried concentrates, potatoes, sugar beets, apple pectin and cane sugar by growing, intact and ileorectostomized swine. 2. Comparison of results

Results of the measuring of the total metabolism of growing intact pigs (INT) and pigs with ileorectal anastomoses (IRA) are compared. The 16 comparisons are based on studies with rations of dried feedstuffs and rations containing between 30 and 50% of the DM raw or steamed potatoes and sugar beets, sucrose and apple pectin. On an average of all comparisons the relative values for the digestibility of energy, DM and the organic matter as well as for the metabolizability of the energy were between 81 and 82% (values measured at INT animals = 100). The comparison also refers to the crude nutrients, the water-soluble carbohydrates, the starch and the pectin. As a tendency, the IRA utilized the metabolizable energy better than the INT animals. The energy maintenance requirement of the IRA animals was--by 15%--significantly higher than that of the INT animals. There is not yet an answer to the question in how far comparative studies of INT and IRA animals make verified statements with regard to the differences in the energetic utilization of the precaecally and postileally digested nutrients possible. For this, further experiments will be necessary.     

The energetic utilization of sugar beets, dried chips, cane sugar and apple pectin by growing swine. 2. Nitrogen and energy metabolism

The energetic utilization of rations with raw and steamed sugar beets, dried sugar beet pulp (16 measured values each), sucrose and apple pectin (8 measured values each) as supplement feed to a basic ration was measured at 4 growing pigs each in the live weight range of between 40 and 130 kg. The utilization of the energy in the rations amounted to 69.1 +/- 5.5, 68.3 +/- 7.1, 60.9 +/- 5.8, 70.5 +/- 4.1 and 69.9 +/- 6.9% (same sequence as above). The utilization values for the supplemented feedstuffs were 69.2 +/- 7.4, 68.0 +/- 10.0, 55.9 +/- 9.7, 72.2 +/- 7.6 and 71.7 +/- 17.3%. The average retention value of the digestible pectin was derived from the test results with dried sugar beet pulp and apple pectin as 5.8 kJ/g. An influence of the ontogenetic development on energy utilization cannot be derived from the comparison of the retention effect of digestible nutrients measured at growing pigs and that derived from adult pigs.     

The energetic utilization of rations with steamed potatoes in growing swine]

The energetic utilization of rations with steamed potatoes (40 and 50% of DM of ration) was measured in 8 growing pigs, live weight 30-70 kg by means of respiration experimental techniques. The experiments were carried out using the difference method (3 periods feeding basal diet and 3 periods feeding basal diet plus potatoes). The digestibility of energy of the steamed potatoes amounted to 94%, that of organic substances 96% and that of crude protein 77%. The metabolizable energy amounted to 16.1 and the energy deposition to 12.0 MJ/kg DM of steamed potatoes, 74.5% utilization respectively. The results in growing pigs are very similar to the results in adult pigs.     

Energetic utilization of sugar beets, dried shreds, sucrose and apple pectin by growing swine. 1. Study overview and composition and digestibility of feed and rations

Total metabolism experiments with a basic ration were carried out over two measuring periods and with a basic ration plus supplements of raw sugar beets, steamed sugar beets, dried sugar beet pulp, sucrose and apple pectin resp. with 4 pigs per test group and 4 test groups (LW 40-135 kg). Live weight gain was approximately equal after the feeding of raw and steamed sugar beets. It amounted to 650 g/animal and day in the first experimental period and to 715 g in the second. After feeding dried sugar beet pulp as supplement the corresponding weight gain was 525 and 565 g/animal and day. In the course of the ontogenetic development up to a live weight of about 70 kg an increase of digestibility could be observed. Adaptation cannot be excluded. This question will be pursued in the following experiments, so that consequences for energetic feed evaluation have to be postponed. For both raw and steamed sugar beets the digestibility of the organic matter was 88%, of NFE 95% and of water soluble carbohydrates 95%.     

The energy utilization of root vegetables and their processed products by adult swine

The energetic utilization of raw and steamed sugar beets, raw carrots and fresh conserved or dried sugar beet pulp was measured at 8 adult pigs each with the application of the respiration experiment method. The experiment was laid out according to the difference method with 4 periods of basic rations per animal. The digestibility of the energy of the 5 feedstuffs (sequence as above) was measured as 85, 87, 83, 67 and 69% and energy retention as 10.1, 9.8, 9.1, 8.2 and 8.1 MJ/kg DM. In comparison to earlier measurings (Schiemann et al., 1966) digestibility was by 4%, relatively, lower. Under consideration of the difference in the digestibility of energy, there is very good agreement in energy retention.     

Measuring energy turnover in the adult swine during feeding of rations with potato starch, potatoes, beets, pressed shreds and coarse fodder as supplements to a basic ration. 1. Energy turnover and energy utilization

25 rations with a wide variation of the content of various carbohydrates (crude fibre 36-185; water-soluble carbohydrates 25-306, starch 272-683 g/kg DM) were fed to male castrates (n = 8) of a live weight between 90 and 180 kg, and energy metabolism was measured. The rations were composed of a cereal basic ration and various feed-stuffs (potato starch-raw and soaked) potatoes (raw and steamed), sugar beet and products from it, maize pellets, dried roughage lucerne, clover, lupin, grass, rye straw meal) as supplements. The digestibility and metabolisability of the energy of the rations ranged between 88 and 62 or 86 and 60% resp. Between 2 and 4% of the consumed energy were lost in urine. The partial utilization of the metabolizable energy of the rations varied between 80% (processed supplement of potato starch) and 52% (supplement of rye straw). The rations with supplements of dried roughage were relatively well energetically utilized-between 63 and 70%. A regressively calculated difference of 17%-units was regressively calculated between the utilization of metabolizable energy of either precaecal or postileal origin.     

The energetic utilization of rations with molasses, dried sugar beets, apple pectin and lucerne leaves by adult swine]

The energetic utilization of 6 rations with molasses, dried sugar beets, apple pectin and lucerne leaves was measured in 8 adult pigs by means of the respiration test technique. The energy digestibility of the rations ranged from 74 to 88%, the partial utilization of the metabolizable energy from 66 to 78%. From the results with apple pectin a mean energy deposition value of 7.2 +/- 12.5 kJ/g digestible pectin was derived. Taking into consideration results from previous recorded experiments and the high standard deviation for estimation of the energetic feed value as deposition effect of digestible pectin, 5 kJ/g are proposed.     

Effect of thermal treatment of potato products on nutrient decomposition in the digestive tract of swine. 1. Passage and digestibility of nutrients in the various portions of the intestine

In addition to a basic ration (barley, dried green fodder, fishmeal) pigs (castrated males, 100 ... 130 kg live weight) received a supplement of raw potato starch, raw ensiled potatoes, cooked potato starch or steamed ensiled potatoes; nutrient and amino acid passage and digestibility (absorption) were measured in the small intestine, the upper large intestine and the total digestive tract with the help of simple cannulae at the distal ileum and the middle of the hind gut and the estimation of the HCl insoluble ash as an indicator. In addition, the amounts of bacteria in faeces were determined and the influence of raw and cooked potato starch on N retention was ascertained. When raw potato products were fed, distinctly higher amounts of dry matter, organic matter and starch pass the ileum, which get into the colon undigested, i.e. the digestibility of these substances is low at the end of the ileum (raw potato starch 24%, starch of raw ensiled potatoes 36%). Up to the middle of the colon there is intensive bacterial starch degradation so that in this place the difference between raw and thermically treated potatoes is only small. No matter what the previous treatment of the potatoes was, there is hardly any starch in faeces, i.e. it was nearly 100% digested up to the end of the digestive tract. The passage and digestibility resp. of ash and crude cellulose from the basic ration is not influenced by the supplement of raw or thermically treated potato products in the individual sections of the digestive tract. At the end of the ileum there are no differences between the apparent digestibility of the crude protein and absorption of amino acids of supplemented raw or cooked potato starch or steamed ensiled potatoes; after the use of raw ensiled potatoes they are, however, significantly more reduced than the comparison of analyses of faeces shows. In the large intestine the high amount of potato starch stimulates the metabolism and the reproduction of faecal bacteria as is shown by an increase by 20-30% in bacteria N excretion in faeces. Apparent crude protein digestibility and amino acid absorption are diminished by that. The increased N excretion in faeces after the supplement of raw potato starch to the basic ration is-in comparison with the supplement of heated starch-compensated by a commensurately lower N excretion in urine so that N retention practically remains uninfluenced by the supplement of variously treated potato starch.(ABSTRACT TRUNCATED AT 400 WORDS)     

Effect of the starch sources barley, corn, potatoes and their ration fractions on the nutrient digestibility and energy utilization in ruminants. 1. Comparative studies of nutrient digestibility in cattle and sheep]

Rations with energy parts of 50, 25 and 10% from barley, maize and potatoes were investigated comparatively by means of total metabolism experiments with oxen with a view to arriving at a more precise estimation equation of net energy fat for cattle. Parallel to the investigations with oxen the energy and nutrients digestibility of the rations in wethers was measured. The crude fibre content of the rations ranged from 166 to 271 g and the starch content from 69 to 330 g/kg DM. The daily starch intake of the oxen ranged from 575 to 2739 g on nutrition level (NL) 1.7 and from 365 to 1804 g on NL 1.1. The energy digestibility of the rations in oxen with energy parts of 50% barley, maize and potatoes was on average 73.5, 73.9 and 75.3%, of the rations with energy parts of 25% on average 72.2, 71.6 and 72.4% and of the rations with energy parts of 10% on average 68.8, 69.5 and 69.8%. The digestibility of energy and nutrients in cattle and sheep was in good agreement excepted crude protein and crude fat; these were digested 4-5%-units lower from cattle than from sheep. The increase of the nutrition level by one unit lowered the digestibility of rations with energy parts of 50 and 25% from concentrates in cattle about 3-6 units and of rations with energy parts of 10% from concentrates about one %-unit. Information about rumen physiological data is given comparatively between cattle and sheep.     

The energy maintenance requirement of growing pigs of different sexes given normal and high protein diets. 3. Experiments in boars

Six fattening boars each, hybrids of line 150(150 X (L X E] received rations with 17 and 45% crude protein. In the live weight range of 36 to 167 kg, 5 periods of growth feeding alternated with 4 periods of maintenance feeding. Compared with maintenance level the nutrition level of 2.7 did not have an influence on digestibility. Nitrogen retention was only insignificantly influenced by the level of protein supply. The maintenance requirement of the animals used was by 50% higher than in previous experiments made by our work team. On average it amounted to 1,017 KJ metabolizable energy per kg LW0.62, i.e. to 1,063 for those animals fed with rations containing 17% crude protein and to 986 for those animals receiving 45% crude protein in their rations. The utilization of metabolizable energy for energy retention amounted to 75% for rations with 17% crude protein and to 70% for rations with 45% crude protein. The partial utilization of metabolizable energy for fat retention was ascertained as 90% and for protein retention as 53% by means of multiply regressive assessment.     

The energy metabolism of growing swine in the liveweight range of 10-50 kg. I. Study design, feed intake and digestibility

Studies of the energy metabolism at maintenance and growth levels after the feeding of rations with a crude protein content of 17-24% and 44-47% resp. were carried out with hybrid pigs of line 150 in the live weight range between 10 and approximately 50 kg. This paper gives information on the methods and the outlay of the experiment and presents results concerning feed intake, live weight development and digestibility. Feed intake increased on average with growing live weight by 30-35 g DM/kg live weight. Feed conversion ranged from 1.2 to 1.8 kg DM/kg live weight gain in the first period and from 2.3 to 3.2 kg DM/kg live weight gain in the last period. The digestibility of the energy in the rations with a crude protein content of between 17 and 24% averaged 80% and that of the rations with a crude protein content of 44-47% averaged 86%. In the course of ontogenetic development the digestibility increased up to about 30 kg LW. The influence of the nutritional level on the level of digestibility was unequal in the experiments. In one experiment a decrease (1% unit) and in two experiments an increase (1-3% units) of the digestibility after the feeding of growth level in contrast to maintenance level could be observed. The change of rations with a varying protein content did not result in an influence on the digestibility level in comparison with the constant feeding of one ration.     

Measuring of the energy turnover in adult swine during feeding of rations with potato starch, potatoes, beets, pressed shreds and coarse fodder as supplements to a basic ration. 2. Evaluation and discussion of the results for further development of energetic feed rating for swine

Energy metabolism measurings of male castrates of a live weight between 90 and 180 kg after feeding rations with a wide variety in the content of various carbohydrates (crude fibre 36-185, water soluble carbohydrates 25-306, starch 272-683 g/kg DM) formed the experimental basis of the considerations. Energy retention depended significantly on the digestibility and metabolizability of the energy, on energy concentration and the crude fibre content of the rations. By means of multiple regression analyses the energetic effect of 1 g digested matter of the carbohydrate fraction was assessed as follows: 12.9 kJ for starch, 12.1 kJ for disaccharides, 11.5 kJ for the remaining water soluble carbohydrates and 10.4 kJ for bacterially fermentable carbohydrates (BFC). There was a difference between the energetic effective value of starch and BFC. This corresponds completely to the difference in the utilization of metabolizable energy between exclusively precaecal and postileal digestion. The following conclusions are drawn for the further development of the energetic feed evaluation for pigs in the framework of the GDR feed evaluation system: --There are to be differentiated fixed values for the retention of digestible carbohydrates for the fractions starch, water soluble carbohydrates (pectin) and bacterially fermentable carbohydrates. --The influence of the digestibility of the energy in the ration on the energetic retention effect of BFC is small. The integration of these variables into an estimation equation for the energetic feed value is therefore not necessary.     

The use of the sugar beet in swine nutrition. 2. The effect of different preparation processes on the apparent prececal and fecal digestibility

With ileum cannulated sows were tested the apparent precaecal and faecal digestibility of crude nutrients from raw and thermically treated fodder sugar beets of size "Rosamona". Two samples from two different harvest years, differing extremely in the content of disaccharides were tested. The crude nutrient digestibility affected stronger by content of sucrose then by treatment. Fodder sugar beets with contents of disaccharide lower then 400 g/kg DM showed low precaecal and faecal digestibilities. A longer cooling phase decreased the feed value of steamed beets through the microbial attack in the formation of precaecal indigestible sugar alcohols (mannitol).     

Studies on growing pigs to determine the true digestibility of variously prepared potatoes. 2. Technically dried potatoes]

There are two kinds of damage to potato proteins that may arise in the process of beat drying. Decreases in the gross lysine content are accompanied by a still much more pronounced depression of digestibility. If, for example, the gross lysine content of dried potatoes was only 50% of that of steamed potatoes then the average value for the true lysine digestibility was 15%; in some cases the content of truly digestible lysine was 0% when compared to that of steamed potatoes. Similarly, it was found that some types of dried potatoes with a dry matter content of about 88% had already lost about 43% of the truly digestible lysine contained in steamed potatoes.     

Determination of the true digestibility of amino acids in variously prepared potatoes in growing pigs. 1. Freshly steamed potatoes and silage made from steamed potatoes]

Freshly Steamed Potatoes of 6 varieties were investigated. With 3 varieties the true N and amino acid digestibilities were found to be in good agreement, while great variations were found in potatoes of the other 3 varities so that it appears to be a matter of some doubt whether the true amino acid digestibility could, in the case of potatoes, be reliably derived from data on the true N digestibility. Differences in the true amino acid digestibility data were found between the varities of potatoes grown in different years. A positive trend was found to exist in the relationship between the absolute amino acid content and true digestibility. The true lysine digestibility of freshly steamed potatoes varies between 76-90%, the average percentage being about 80%. The true methionine digestibility was found to vary within still wider limits, although the average percentages was also about 80%. Values established for the true cystine digestibility ranged from 80% to 90%. The true amino acid digestibility data did not provide a sufficiently reliable basis for making conclusions as to the existence of a limiting amino acid. Both the lowest value for true digestibility and the greatest variations were found in the case of the amino acids alanine, tyrosine, and methionine. It was observed that silage made from steamed potatoes had a lower true digestibility of N than steamed fresh potatoes although the value for true amino acid digestibility were the same, with the exception of methionine and cystine.     

The energy maintenance requirement of growing pigs of different sexes given normal and high protein diets. 1. Experiments in castrates

Energy retention was measured alternately at 12 barrows, fattening hybrids of line 150 (150 X (L X E], at maintenance level (4 periods) and growth feeding (5 periods) in the live weight range between 32 and 134 kg, 6 animals each received rations with 17 and 45% crude protein resp. during the complete experimental period. The nutrition level did not have a significant influence on the digestibility level of the feed. The experiments carried out at maintenance level showed that the maintenance requirement of metabolizable energy in the experiments with 17% crude protein in the ration was 941, in the experiments with 45% crude protein in the ration 913kJ ME/kg LW0.62 and on average 927 kJ ME/kg LW0.62. Including the experiments with growth feeding one can conclude from a regression analysis, largely in agreement with the measured values, that 955 kJ ME/kg LW0.62 is the energy maintenance requirement. These values of maintenance requirement are by 50% higher than those derived from previous measurings. In contrast to expectations, the increase of protein concentration in the ration did not result in a higher energy maintenance requirement. The utilization of metabolizable energy for retention amounted to 74% for rations with a normal protein content and to 65% for those with a high protein content. The multiply regressive evaluation showed a utilization of metabolizable energy for fat retention of 79% and for protein retention of 53%.     

The energy metabolism of growing swine in the body weight range of 10-50 kg. 2. Nitrogen and energy metabolism

Investigations were carried out about nitrogen and energy metabolism feeding rations with 17-24 and 44-47% crude protein content on maintenance and growing level to castrated male hybrid pigs of line 150. In growing periods the N deposition amounted to 10 g/animal.d (15 kg live weight), 18 g/animal.d (30 kg LW) and 21 g/animal.d (greater than 40 kg LW) on lower protein feeding level. In experiments with higher protein feeding level the corresponding results were 17, 22 and 22 g N deposition/animal.d. The partial utilization of metabolizable energy for deposition amounted to 70% for the rations with 17-24% protein content and to 59% for the rations with 44-47% protein content, without correlation to the animals development and the alternation in the protein feeding level. The results of regression analysis about maintenance requirement were 814, 775 and 806 kJ metabolizable energy/kg LW0.62.d in trials feeding rations with 17-24% crude protein content as well as 764, 846 and 818 kJ metabolizable energy/kg LW0,62.d in trials feeding rations with 44-47% crude protein content. 1,5-1,8 MJ metabolizable energy were used per MJ protein energy deposition and 1,3-1,4 MJ per MJ fat energy deposition respectively. The energy deposition per kg live weight gain amounted to values between 9 (10 kg LW) and 18 MJ (60 kg LW).     

The energy utilization of alfalfa leaf by adult swine]

By means of the respiration test technique the energy metabolism of adult pigs fed with a basic ration plus alfalfa leaves with 110-200 g crude fibre/kg DM was measured in 3 test periods. The digestibility of the energy of the alfalfa leave ranks amounted to--decreasing with increasing crude fibre content--66, 60 and 59%; the respective energy retention values were 7.5, 6.9 and 6.9 MJ NEFs or 510, 470 and 470 EFs/kg DM. According to the measured values there were no significant differences in the digestibility of the energy and in the energy concentration of NEFs between fresh and dried alfalfa leaves of largely equal chemical composition.     

Vitamin A requirement of growing swine. 1. Effect of vitamin A supply on growth of piglets and fattening swine

For the purpose of ascertaining the vitamin A requirement seven experiments with 303 pigs in the live weight range between 6.5 and 114 kg were made. In three experiments under in practice conditions we checked the standard vitamin A supplement to the mixed feed with 1,732 pigs (live weight range between 8.5 and 110 kg). The supplement to vitamin-A-free rations and to those poor in or free of carotene amounted to between 0 and 8,000 IU/kg feed. Above that, between 0 and 16 mg beta-carotene and 1,000 mg nitrite/kg feed were supplemented. As long as the vitamin A store in the liver during weaning amounted to greater than 50 IU and greater than 100 IU/g at the beginning of fattening, feed intake, live weight growth and feed expenditure were not influenced by the supplement of vitamin and provitamin resp. The supplement of 250 IU resulted in the same weight growth from weaning to the end of fattening as that of 4,000 IU. Nitrite supplement had a negative effect at 250 IU, at 500 IU vitamin A consumption and weight growth tended to be only insignificantly lower. The methaemoglobin content decreasing in the course of the experiment reflects the adaptation of the pigs to the nitrite load. The consumption and growth depression caused by vitamin A deficiency could be observed from the 7th week of the experiment when casein-swelling starch rations were fed, but from the 13th week of the experiment only when cereal-soybean oilmeal rations were fed. The weight of liver, spleen, kidneys, heart and brain was not influenced by vitamin A supply. The same applies to the body composition and retention with the exception of two deficiency piglets, which contained less fat in the empty body than the control animals.     

Energy metabolism of cocks and broiler chickens fed on diets with different carbohydrate sources.

Energy balances of cocks and chickens were measured using the nitrogen-carbon-balance method. In Experiment 1 twelve adult White Leghorn cocks were fed alternately on a basal ration or on a supplemental ration composed of 75% basal diet and 25% carbohydrate source as a supplement. In Experiment 2 six groups of 12 male broiler chickens were fed successively on two diets each with different carbohydrate sources (40% of DM) and on two energy levels. The investigated carbohydrate sources were glucose, fructose, sucrose, maize starch, raw and steamed potato starch, dried sugar beet pulp, tapioca, wheat, maize, rye and barley. In both experiments the energy digestibility of the diets with raw potato starch, beet pulp and barley was significantly lower compared to the other diets. Digestibility of those ranged from 88 to 81%. By simple linear regression no significant differences in efficiency of utilisation of ME of the diets between the carbohydrate sources sugars, starches and cereal grains could be proved. The corresponding MEm values agreed very close among the diets (411 to 429 kJ.kg BW-0.75.d-1).