Joint research on the precise determination of the energy and protein requirements of fattening pigs. 5. The effect of the crude protein concentration in the isocaloric diet on the fattening performance of swine of the Bulgarian Landrace

Live weight development and feed expenditure on 3 levels of crude protein supply and with isocaloric rations were investigated in scientific feeding experiments with 7 castrated male pigs each of the Bulgarian land race in the live weight range between 30 and 100 kg with a subdivision at 60 kg. The crude protein concentrations in the rations for the 3 groups were 17%, 15% and 13% in the first fattening period and 15% 13% and 11% in the second fattening period. In the two fattening periods the digestibility of the feed mixtures used was ascertained in experiments. The daily live weight gain in the three groups over the whole fattening period reached a high level of performance (836 g, 778 g and 757 g). The feed expenditure values were 3.3, 3.7 and 3.7 kg mixed feed (88% dry matter) per kg live weight gain. The highest protein supply resulted in the best weight gain performance and the lowest feed expenditure.     

Joint research on the precise determination of the energy and protein requirements of fattening pigs. 7. The effect of various energy levels on the performance and feed expenditure of fattening pigs

Scientific feeding experiments were carried out with 7 male castrated pigs of the genetic origin land race pig X large white with the test animals fed individually and the rations containing approximately the same amounts of protein, amino acids, minerals and vitamins but varied amounts of energy. Energy intake was adjusted to three levels: 100%, 85% and 70% of semi-ad-libitum intake (group 1 = 100%). With regard to protein supply there was a subdivision into 30-60 and 60-100 kg live weight. In addition to this, the digestibility of the feed mixture used and the N-balance were determined in both fattening periods. Having reached 100 kg live weight, the animals were slaughtered and a number of slaughtering parameters was determined. The average daily live weight gain in the three test groups was 749, 664 and 540 g over the whole fattening period. The feed expenditure was 3.7, 3.9 and 4.3 kg mixed feed per kg live weight gain so that, with regard to live weight performance and feed expenditure the group with the highest energy supply showed the best results. The level of energy supply had a remarkable influence on the composition of weight gain; thus the amount of fat in the carcass of the animals of groups 3 was by 1.8 kg and 2.5 kg resp. lower than of the animals in groups 2 and 1.     

Joint research on the precise determination of the energy and protein requirements of fattening pigs. 4. The effect of the energy level on the fattening of Camborough-type hybrid swine

Scientific feeding experiments were carried out with 5 castrated male pigs and 4 female animals of the genetic origin "Camborough" in the live weight range between 30 and 100 kg with a subdivision at 60 kg. In each test group the animals were fed individually and received rations with approximately equal contents of protein, amino acids, minerals and vitamins but different energy contents. Energy intake was adjusted to 3 levels of 100%, 85% and 70% of semi-ad-libitum intake. Apart from that, the digestibility of the feed mixtures used in the 2 fattening periods was determined. Having reached a live weight of 100 kg, 7 representative animals per group were slaughtered and a number of slaughtering parameters were registered. In all three test groups the daily live weight gain over the complete fattening period was very high (846, 819 and 778 g). Though the weight gain in group 3 with 70% of the energy supply of group 1 is significantly lower than in the other two groups, it is, however, only 70 g lower than in group 1. Consequently, the feed expenditure (2.6 kg mixed feed per kg live weight gain) in group 3 is by 20% lower than in group 1, in which the feed expenditure is 3.2 kg mixed feed per kg live weight gain. There were no significant differences on the weight gain performances and the registered carcass parameters between sows and castrated male pigs. Observed deviating tendencies are discussed.(ABSTRACT TRUNCATED AT 250 WORDS)     

Lysine requirement of fattening boars in respect to their performance. 1. Influence of the consumption of energy and amino acids on the fattening performance

With a total number of 157 boars 9 feeding variants with different levels of energy and amino acids were checked. The weight increase per fattening day and the energy and lysine expenditure per kg live weight increase were determined. The insufficient supply with lysine had negative effects on the live weight increase and the energy expenditure during the whole fattening period. Between the variantes with a high supply with amino acids (120%) and the supply according to standard (100%) no significant differences concerning the live weight increase could be ascertained up to 90 kg live weight. Between 90 and 120 kg live weight the animals in the variant with medium energy level and 120% lysine supply achieved significantly higher increases than those in the standard variant. Up to 90 kg live weight the energy expenditure for all groups amounted to 2,08 kEFs (energetic feed units for pigs) per kg live weight increase. The most suitable results were achieved by the animals which received the variants rich in energy (1,760 resp. 1,770 kEFs per kg live weight increase). Above the 90 kg live weight limit the energy expenditure rose considerably, remained however under 2,000 kEFs per kg live weight increase for the boars of the variant with medium energy level and 120% lysine supply as well as for the variant rich in energy and 100% lysine supply. The lysine expenditure in the first variant amounted to 25.1 g per kg live weight increase and for the variant rich in energy to 20.6 g lysine per kEFs.     

Studies on the performance-related lysine requirement in fattening pigs. 1. Influence of energy and aminoacid intake on fattening

A total of 110 barrows fed varying levels of energy and amino acids in 8 treatments, were tested. The weight gains per fattening day and energy expenditure were found to be mainly determined by energy intake. Up to a liveweight of 100 kg both low and high levels of amino acid supply produced the same fattening performance results as amino acid supply to standard. In the 100-120 kg liveweight range, the animals fed higher levels of protein proved slightly superior. As to energy expenditure, animals subjected to restricted feeding up to 70 kg liveweight and fed full rations later, consumed 2.22 kEFs (2.22 kilo energetic feed equivalents/swine) per kg gain and proved significantly superior to those animals that were very intensively fed at the beginning and put to restricted feeding beyond 70 kg liveweight (2.53 kEFs per kg gain) as well as to those receiving high levels of energy all the time (2.39 kEFs/kg gain). In the latter case, 23 g of lysine were required per kg gain.     

Effect of the polyether antibiotic "monensin" on fattening and slaughtering performance as well as protein and energy retention in bulls

In an individual feeding experiment (150-500 kg live weight) the influence of the polyether antibiotic Monensin on the fattening, slaughtering and retention performances of crossbreeding dairy bulls (genotype 31) and fattening hybrids (genotype 61) was ascertained. The supplementation of the polyether antibiotic on average resulted in a decrease by approximately equal to 11% of the dry matter and energy expenditure per kg weight gain due to a lower feed intake and a higher live weight gain. The slaughtering parameter investigated and the chemical composition of the empty body remained uninfluenced. The daily nutrient retention values were positively influenced by the Monensin supplementation since the fattening bulls of the test group required 30 days less to achieve the attempted fattening weight. The additional retention of protein, fat and energy per animal and day in the dairy bulls approximately equal to 10.9; 13.5 and 16.4% and in the fattening hybrids 1.9; 3.2 and 2.6%. Due to a higher energy retention at a lower level of feed and energy intake after Monensin supplementation an average of approximately equal to 11.3 and 15.4% resp. more of the consumed digestible protein and the digestible energy resp. were retained in the empty bodies. One can conclude that Monensin improved the utilisation of feed energy; obviously the effect of the polyether antibiotic is due to its influence on processes in the rumen or directly or indirectly on metabolism.     

The rearing of female twin cattle using only feed pellets in comparison with straw pellets plus a concentrate mixture. 2. Weight gain and feed consumption as well as rumen fermentation in the 1st half of the 2d year of life

In investigations with 30 young cows (twin cattle) the applicability of straw materials as sole roughage was tested during the first half of their second year of life (183 feeding days). In the course of the experiment sole feed pellets (I) and partly pelleted rations of dried feed (straw pellets plus loose wheat and loose wheat straw resp.; II) were used. Approximately 72% of the dry matter intake was provided from straw materials in both groups and on an average of the test period. Weight gain and feed expenditure were ascertained and at the end of the test period also the parameters of rumen fermentation and of the concentration of some metabolism parameters in the blood serum. With feed supply being restrictive (2.2 kg dry matter/100 kg live weight), a high dry matter intake from straw (1.6 kg/100 kg live weight or 4.8 kg/animal and day resp.) and average weight gains of between 574 (I) and 582 g (II) were achieved. The standard expenditure of energy (kEFUcattle) and protein stated in the GDR feed evaluation system for this period of development was undercut by 27 (II) and 29 (I)% and 12 (II) and 18 (I)% resp. On average the expenditure of kEFUcattle/kg weight gain was 4.75 (I) and 4.98 (II) and that of digestible crude protein/kg weight gain 679 (I) and 733 g (II). Compared to standard values the expenditure of energy and feed expenditure from concentrates was 80%. Rumen fermentation conditions corresponded to those of a high cellulolytic activity (C2: C3 ratio of greater than 4: 1). The only significant differences between the groups at the time of sampling were to be observed in the total concentration of volatile fatty acids and in the pH-value in the rumen. The absolute (1/animal) and relative (1/kg dry matter intake) volume of rumen fluid varied between 65 and 70 and between 10.5 and 12.5 1. The ascertained concentration of selected metabolism parameters were within the physiologic standard range.     

Requirements of Muscovy ducks (Cairina moschata domestica) for crude protein and energy levels of fattening diets

Groups of male and female Cairina ducks subjected to equal starter feeding (1st to 3rd weeks) were used from the 4th week of live (fattening period) to test feed mixes of varying energy and crude protein levels (480 energetic feed equivalents/heu[EFH] - 140 g crude protein[CP]; 480 EFh - 180/g CP; 555 EFh - 140 g CP; 555 EFh - 180 g CP; 625 EEh - 140 g CP; 625 EFh - 180 g CP - all figures referred to 1 kg of feed). The different energy levels remained without influence of the live weight development. High-energy feed caused, however, higher expenditures of energetic feed equivalents per kg of gain and resulted in carcases with higher fat proportion. At all the 3 energy levels under study, high-protein feeding proved superior to low-protein rations with regard to live weight gains and meat yield. For the time being, 500 EFh and 180 g CP per kg of organic matter are recommended as indicators for Cairina duck fattening rations.     

Urea utilization of growing lambs. 2. Growth experiments

In two growth experiments with 30 lambs per group the influence of urea (1-2% of the ration) and straw (20-30% of the ration) on the performance was studied under conditions of intensive fattening. The content of native crude protein in the rations varied between 10.1 and 18.4% of the DM. In experiment 1 the lambs of the two groups which received mixed feed for fattening lambs without urea on average consumed with 1.02 and 1.11 kg DM resp., 696 and 757 EFUcattle resp. and 173 and 189 g crude protein resp. per animal and day. The groups with wheat or barley and urea consumed 1.06 and 0.96 kg DM resp., 714 and 627 EFUcattle resp. and 209 and 155 g crude protein resp. Their weight gain of 247 g/animal and day was 24% and that of 230 g resp. 26% higher than that in the control groups without urea. The lowest dry matter intake (0.91 and 0.82 kg resp.) was shown by the animals of the groups which received wheat or barley without urea. In the second experiment the control group achieved an average daily weight gain of 327 g at an expenditure of 2.24 kEFUcattle/kg weight gain. Despite a partly higher dry matter intake, the daily EFUcattle intake was between 12.2 and 24.5% lower in the straw groups and energy expenditure increased between 12.0 and 27.8%. Urea supplements of between 1 and 2% improved dry matter, EFUcattle and crude protein intake and thus weight gain.     

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.     

Rearing of female cattle twins using complete feed pellets in comparison to straw pellets plus concentrate mixture. 1. Weight gain performance and feed expenditure as well as rumen fermentation conditions during the 4th-12th months of life

The investigations with young female cattle (twin cattle, n = 30) the applicability of straw as sole roughage after the end of the suckling period was tested. Completely (I) and partly (II) pelleted rations of dried feed with a straw component of 65% each in the total rations were used. Feed intake, development of body weight, feed expenditure as well as indexes of rumen fermentation and of the concentration of some metabolism parameters in the blood serum were measured. In the complete test period (between 5th and 12th months of life, 243 days) there were not any significant differences between the groups in all registrations. Average daily weight gains of 570 g were achieved with an overall high dry matter (2.6 kg/100 kg live weight) and roughage (straw) intake (1.6 kg dry matter/100 kg live weight). The standard expenditure of energy and protein given for the stage of development was differentiatedly undercut. The energy expenditure being below the standard (ca. 10%), the total energy expenditure (kEFUcattle) was by 20 (II) and 25% (I) below standard expenditure. Energy expenditure aimed at weight gain reached very satisfactory values with 3.68 (I) and 3.79 kEFUcattle/kg weight gain (II). Protein expenditure fell short of the standard for the development stage by 14 (II) and 20% (I) resp. All parameters ascertained of the rumen and intermediate metabolism were in the physiologic standard range, as is characteristic of feeding regimes with a relatively high quota of roughage.     

Joint research on the precise determination of the energy and protein requirements of fattening pigs. 2. Energy and nitrogen metabolism of fattening hybrids in the fattening range of 30 to 120 kg

In 3 experiments a total of 242 total metabolism experiments with ad libitum feeding (experiment 1), 75% (experiment 2) and 62% (experiment 3) of the energy level of the 1st experiment and approximately equal protein and amino acid doses in experiments 1-3 were carried out with 8 castrated male fattening hybrids each (large white X land race pig) X line 150) in the live weight range between 30 and 120 kg. On average, feed intake over the whole live weight range was 2.24; 1.79 and 1.50 kg/animal and day, the corresponding daily live weight gain was 729, 533 and 396 g. With regard to the digestibility of the energy and the nutrients and the metabolisable energy in % of the gross energy there was no relation to the development of the animals. The intake of metabolisable energy per kg live weight decreased with ad libitum feeding and with the advancing development at the end of the experiment in contrast to the beginning of the experiment to 53%, energy retention to 56%. The utilisation of metabolisable energy for body energy retention, taking account of a maintenance requirement of 450 kJ/kg live weight 0,62 on the average of the 3 experiments was 68.4 +/- 1.9, 70.3 +/- 2.0 and 64.3 +/- 2.6%. Energy retention in experiments 1 to 3 amounted to 8.6, 6.8 and 5.3 MJ at the beginning and to 18.1, 12.2 and 8.0 MJ per animal and day at the end of the experiment. Protein energy retention of the pigs (live weight 40 kg) was 26% of the total energy retention in experiments 1 and 2 and 49% in experiment 3. In experiments 1 and 3 protein retention decreased to 15% of the total energy retention, in experiment 2 protein retention remained constantly at 22% between 60 and 110 kg live weight and then decreased to 18%. Consequently, the N-balances were 23-16 g, 16-20 g and 16-9 g/animal and day. The chemical composition of the carcasses was strongly influenced by the level of nutrition. At the beginning of the experiment the protein content averaged between 49 and 57% and the total fat content between 31 and 38% of the dry matter. At the end of the experiment the carcasses of the animals from experiments 1-3 had crude protein contents of 28, 33 and 42% and total fat contents of 66, 61 and 50% of the dry matter.     

Performance dependent lysine requirement of fattening pigs. 3. Effect of amino acid and energy intake on fat, protein and lysine deposition of swine

The gain in structural matter had a linear course with a corresponding feeding intensity and depending on the period of fattening. However, the animals given high-energy diets deposited 130 g protein per day during the first fattening period, this deposition being compensated in the course of further growth by a considerably lower deposition in the sense of aequifinality. Up to a live weight of 70 kg, animals subjected first to restricted feeding and then to fully balanced feeding revealed the highest protein deposition during the last period of fattening, this fact emphasizing the leanmeat character of the animal material used. The daily fat deposition was found clearly determined by energy intake and independent of amino acid supply. Lysine conversion was influenced by the intake of lysine and energy. Under feeding to norm it reached some 40 and 30% during the first and second periods of fattening, respectively.     

Investigations concerning the use of the rumen fermentation regulator monensin in feeding fattening bulls

In two digestion experiments with wethers and seven feeding experiments with 198 fattening bulls with rations rich in (greater than 55% of the dry matter intake from roughage), the influence of the antibiotic monensin on the digestibility of the ration, on rumen-physiologic characteristic values and on fattening and slaughtering results was investigated. The digestibility of the organic matter and the crude nutrients was not significantly influenced by the use of monensin (20 mg/kg dry matter). The administration of 200 mg monensin per fattening bull and day resulted in an increase of the molar concentration of propionate in the rumen fluid by 9.7 mol%, the concentration of acetate and butyrate decreased by 7.3 resp. 2.8 mol %. On an average of the seven experiments the intake of dry matter was diminished by 5.1% through the use of monensin, the live weight increase remained almost unaffected (3.0% additional increase), feed and energy requirement per kg live weight were improved by 7.9%. The fattening results do not always correspond in the various experiments. The results of the dressing of the carcass, the composition of the carcass and the quality of the meat remained unaffected by the administration of monensin.     

Joint research on the precise determination of the energy and protein requirements of fattening pigs. 3. The energy requirement of hybrid swine

The energy requirement for hybrid pigs ((large white X land race pig) X line 150) in the live weight range between 35 and 120 kg is derived from 242 measurings of the total metabolism as the sum of energy requirement for maintenance and energy requirement for live weight gain. Energy requirement is estimated by means of the following equation: (Formula: see text). Energy maintenance requirement, energy content per 1 kg live weightgain in dependence of the daily gain and the derived energy requirement for growth and fattening are compared with corresponding results from investigations with pigs of the species large white and land race pig. Essential differences concerning parameters of energy metabolism determining the requirement could not be detected.     

Lysine requirement of fattening sows depending on their performance. 2. Relations between energy consumption and live weight increase

105 growing sows in the live weight range were fed with 7 test rations with graduated energy and amino acid levels. The growth intensity was very much influenced by the daily energy consumption. On the basis of regression analysis the following linear relation between daily weight increase (y in g per kg live weight0,75) and the daily energy consumption (x in energetic feed units for pigs per kg live weight0,75) was calculated: y = -13,79 + 0,7037 x (r = 0,84, sb -0,0295). The interpolation with regard to live weight balance resulted in a maintenance requirement of 19,8 energetic feed units for pigs resp. 70 kcal net energy fat for pigs per kg live weight0,75. The methods of assessment chosen showed an increase of the energy requirement per 100 g additional live weight increase per day of a constant amount, independent of the live weight, of 142 energetic feed units for pigs resp. 497 kcal net energy fat for pigs.     

Effect of iodine, copper and zinc additions to the diet with a high proportion of coarse rape meal extract on the growth and thyroid function of fattening pigs. 1. The effect on fattening performance

In three experiments with fattening pigs the supplementation of a ration with 8% rapeseed oilmeal (RSO) with 1 mg J/kg resulted in an increased weight gain per day of 31, 94 and 87%. On the other hand, only 83, 76 and 84% of the weight gain of the soybean oilmeal control groups were achieved. The additional supply with 250 mg Cu (experiments II and III) increased the weight gain to 84 and 96% in comparison to the unsupplemented control groups. The combination of J + Cu + Zn lead to the same performance as that of J + Cu (experiment III). In the RSO groups without J-supplement changes in body proportions and parakeratosis could be observed after approximately equal to 7 weeks. After the sole supplementation of Cu these symptoms occurred approximately equal to 4 weeks later. In vitro, the supplementation of RSO with a CuSO4 solution resulted in a decrease of vinylthiooxazolidon and isothiocyanate in line with the CuSO4-concentration. 0.2 mg J/kg feed (experiment III) resulted in the same fattening performance as the supplementation of the ration with 1 mg J and outwardly visible deficiency symptoms. The results show that Cu, depending on its quota, results in a decrease of goitrogenics in the feed and that J and Cu supplementation to rations with rapeseed oilmeal have an additive effect and that parakeratosis can be prevented by J-supplementation.     

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%.     

Performance dependence of the lysine requirement of fattening sows. 1. Effect of energy and amino acid consumption on fattening performance

Seven variants with graduated energy and amino acid levels were tested at 105 growing sows in a live weight range between 30 and 120 kg. The weight increase and the energy expenditure showed a distinct dependence on the energy level of the ration and are mainly determined by the energy intake. Up to a live weight of 90 kg a 20% lysine over- or undersupply in comparison with the norm had no influence on the growth intensity of the animals. On the low and medium energy levels there was a tendency of superiority of the animals which received feeds rich in protein in the section between 90 and 120 kg. In the variant with a high energy level, however, a diminishing increase was detected in the last third of the fattening period in connection with the growing lysine level. The overall most suitable result was achieved in variant M 120 with a daily increase of 675 g and an energy expenditure of 2.04 kilo energetic feed units for pigs per kg increase.     

The energy preservation requirements of growing pigs of different sexes fed normal and high protein diets. 5. Comparison with the results obtained from castrated pigs, sows and boars

In one experiment each with castrated pigs, sows and boars (hybrid pigs of line 150), two groups of six animals received rations containing 17 and 45% crude protein resp. over the complete test period from 35 to 130 kg (castrated pigs), 150 kg (sows), 170 kg live weight (boars) and passed alternatively through a total of 60 metabolism periods on growth and 48 on maintenance level. There were significant differences between the 3 categories of animals with regard to energy maintenance requirement in the relation of 100:105:110 for castrated pigs less than sows less than boars. In contrast to the estimated values derived from previous studies for energetic maintenance requirement of 650 kJ/kg LW0.62.d the measured values for all 3 animal categories are by approximately 50% higher. The protein content did not have an influence on the maintenance requirement of metabolizable energy of the animals. The utilization of metabolizable energy of the two rations for body energy retention corresponds to the expectations with regard to its dependence on nutrients. The requirement of metabolizable energy for protein and fat retention is 1.7:1.0. The energy content of the weight gain of boars was, on average, 85% of that of castrated pigs and sows. The studies of blood parameters did not show any deviations in the parameters tested.