[Nutritional physiology effect of dietary fats in the diet of growing pigs. 1. Effect of an isocaloric exchange of carbohydrate energy compared with fat energy on protein retention, in vitro synthesis of fat from glucose and on several blood parameters in piglets]

Comparison of methods for the effective evaluation of the energy content of poultry byproduct meal for beagles

The objectives of this study were to compare the energy values of poultry byproduct meal (PBM) as feed for adult beagle dogs using the direct, difference, and regression methods to examine dogs' nitrogen metabolism, energy utilization, gaseous metabolism, and body health. Five groups of six 12 mo old female beagles with an average body weight of 9.67 ± 0.52 kg were tested in a 5 × 6 incomplete Latin square design, with six repetitions in each group. Five experimental diets were tested consisting of 100% PBM; three substitution diets containing either 15%, 30%, or 45% PBM (termed 15PBM, 30PBM, and 45PBM, respectively); and a basal diet (included 6.90% PBM). Each experimental period lasted for 10 d, comprising 4 d of dietary acclimation followed by 6 d of testing (including 3 d feeding period and 3 d fasting period), during which the heat production (HP) was determined and feces and urine were collected. Results showed that, in the feeding state, the nitrogen intake, urinary nitrogen, apparent nitrogen digestibility, retained nitrogen, andHP increased significantly (P < 0.05) as the PBM level increased. The net protein utilization, biological value of protein, and total apparent digestibility of amino acids did not differ between the 30PBM and 45PBM diets (P > 0.05). The O2 consumption and CO2 production of beagles during the fasting period were not influenced by the PBM level (P > 0.05). The digestible energy and metabolizable energy values of the PBM estimated by the regression method were 20.16 and 18.18 MJ/kg dry matter (DM), respectively, and did not differ from those determined by the direct method (P > 0.05). The fecal DM percentages and fecal PBM scores were significantly higher in the PBM diet than in the difference method groups (P < 0.05). The direct method group had a significantly higher fecal score (4.63) than the other groups (P < 0.05), The fecal score of the 45PBM diet (3.50) was significantly higher than the 30PBM diet (2.90; P < 0.05). In summary, the direct and difference methods of determining the effective energy value of PBM for beagles, produce significantly different results. Under the conditions of this test, the best proportion of PBM in beagle feed for optimum energy provision is 30%.

Oxidation of dietary stearic, oleic, and linoleic acids in growing pigs follows a biphasic pattern

We used the pig as a model to assess the effects of dietary fat content and composition on nutrient oxidation and energy partitioning in positive energy balance. Pigs weighing 25 kg were assigned to either: 1) a low fat-high starch diet, or 2) a high saturated-fat diet, or 3) a high unsaturated-fat diet. In the high-fat treatments, 20% starch was iso-energetically replaced by 10.8% lard or 10.2% soybean oil, respectively. For 7 d, pigs were fed twice daily at a rate of 1200 kJ digestible energy · kg(-0.75) · d(-1). Oral bolus doses of [U-(13)C] glucose, [U-(13)C] α-linoleate, [U-(13)C] stearate, and [U-(13)C] oleate were administered on d 1, 2, 4, and 6, respectively, and (13)CO(2) production was measured. Protein and fat deposition were measured for 7 d. Fractional oxidation of fatty acids from the low-fat diet was lower than from the high-fat diets. Within diets, the saturated [U-(13)C] stearate was oxidized less than the unsaturated [U-(13)C] oleate and [U-(13)C] linoleate. For the high unsaturated-fat diet, oxidation of [U-(13)C] oleate was higher than that of [U-(13)C] linoleate. In general, recovery of (13)CO(2) from labeled fatty acids rose within 2 h after ingestion but peaked around the next meal. This peak was induced by an increased energy expenditure that was likely related to increased eating activity. In conclusion, oxidation of dietary fatty acids in growing pigs depends on the inclusion level and composition of dietary fat. Moreover, our data suggest that the most recently ingested fatty acids are preferred substrates for oxidation when the direct supply of dietary nutrients has decreased and ATP requirements increase.

The influence of ergot-contaminated feed on growth and slaughtering performance, nutrient digestibility and carry over of ergot alkaloids in growing-finishing pigs

Diets containing 0, 1 and 10 g ergot (Claviceps purpurea) per kg, corresponding to mean total alkaloid contents of 0.05, 0.60 and 4.66 mg/kg (sums of ergometrine, ergotamine, ergocornine, alpha-ergocryptine, ergocristine, ergosine and their -inine isomers analysed by a HPLC-method), were each fed ad libitum to 12 pigs in the BW range of 30-115 kg to study the effect of ergot-contaminated feed on growth and slaughtering performance and the carry over of ergot alkaloids. Additionally, balance trials were conducted to investigate the digestibility of nutrients. Tendencies towards reduced feed intake and BWG were observed at a feeding level of 4.66 mg total alkaloids per kg diet. Typical symptoms of ergot poisoning were not observed. Heart and spleen weights showed significant linear increases. Differences in carcass quality due to dietary treatment were not detected. No genuine ergot alkaloids were found in physiological samples. The balance trials demonstrated a significantly decreased protein digestibility for the most highly supplemented diet.

[The performance of weaned piglets after a five week weaning period in relation to the weaning weight, the feed composition and the use of an effective ergotropic]

In a three-factorial experiment with 216 piglets of the same age (33 +/- 4 days) but a different weight (weaning weight from 5.5 to 9 kg) a conventional piglet rearing feed containing 20% crude protein (standard), a high-energy diet and a low-protein diet (16% crude protein) were tested. In three weaning weight classes the three diets were fed without or with Bisergon [2-N-(2-hydroxyethyl)-carbamoyl-3-methylquinoxaline-1.4-dioxide] over a period of 21 days. From the 22nd to the 71st day after weaning all the piglets received the standard diet without ergotropic. Among the factors studied the Bisergon supplement had the biggest effect. The additional weight gain varied from 9% in case of heavy piglets fed the high energy diet to 150% in case of light piglets fed the low protein diet. The ergotropic improved feed conversion by 22% and lowered the frequency of gastrointestinal diseases requiring treatment by 28%. At the end of the rearing period the weight of the piglets initially fed with Bisergon (means = 34.6 kg) was significantly higher than that of the control animals (means = 31.6 kg). The weaning weight and the diets influenced the final weight especially in the groups without ergotropic. In this case the piglets fed with the high-energy diet gained 30% more and those fed with the low-protein diet 40% less compared with the standard group. The average live weight gain of the light piglets (weaning weight 6.1 kg) was 30% lower than that of the heavier piglets (weaning weight 8.5 kg). The frequency of treatment against diarrhoea of the heavy piglets was by one third lower than that of the light animals. The piglets fed with the low-protein diet appeared to show a limitation of gastrointestinal diseases, but these animals also had the lowest feed intake. Independent of the Bisergon supplementation the weaning weight clearly influenced the live weight after the 10-week experiment. The initially better development of the animals started with the high-energy diet was compensated. In contrast to this, the piglets weighing 6.1 and 7.2 kg fed with the low-protein diet could not compensate the retarded development in comparison with the piglets fed with the standard or the high-energy diet. This experiment confirms the enormous improvement of the performance and of the health status of weaned piglets caused by the ergotropic Bisergon.(ABSTRACT TRUNCATED AT 400 WORDS)

Interactive effects of live weight, basal diet and fat supply on essential fatty acid status and blood concentrations of glucose, insulin and thyroxine measured postprandially in pigs

1. The composition of the basal diet (purified vs complete feed ingredients provided as a cassava and a barley based diet, respectively), type of dietary fat [saturated fatty acids (18:0) supplied as fully hydrogenated soya bean oil vs unsaturated fatty acids (18:2) supplied in the form of soya bean oil] and the live wt of the animals (40 vs 80 kg) highly influenced the EFA status of the body and postprandial blood concentrations of glucose, insulin and thyroxine. 2. Interactive effects of live wt, type of basal diet and fat supply on EFA status and postprandial blood levels are discussed.

[Use of partly hydrolyzed and untreated straw meal in the feeding of breeding sows. 4. Influence on embryonic mortality and fertility]

The influence of a supplement of variously treated straw materials to a ration to dry concentrate (= 1), (untreated = 2, steamed = 3, HCl-treated = 4 and partly hydrolysed = 5) during gestation on fertility and rearing performance, the embryonic survival quota of fertilized ova as well as on some selected metabolites in the blood serum was studied in 3 experiments. The integration of untreated straw meal resulted in significantly diminished performances in comparison to test groups 1 and 5 in all tested parameters of fertility and rearing performance (weight of litter). The best results were achieved in all experiments with rations of concentrate and partly hydrolysed straw meal. The individual test groups the following performance values (number of piglets born alive, weight of litter in kg) were achieved: 1 = 9.3, 12.3; 2 = 6.5, 8.2; 3 = 7.5, 9.6; 4 = 8.6, 12,4; 5 = 10.6, 14.4). Ration specific reactions could only be proved for the parameters glucose and urea out of the metabolites (insulin, glucose, cholesterol, urea tri-iodine thyronine and thyroxine).

[Nutritive physiological effects of dietary fats in rations of growing swine. 6. Effect of soya oil and lard on growth performance and carcass characteristics and various blood parameters in fattening swine]

Groups of each 10 boars, weight range 20-60 kg, were fed ad libitum the following 4 rations of similar protein: energy ratio: Ration I (control), Ration II (+ 2% soyaoil ), Ration III (+ 2% soyaoil + 5% lard), Ration IV (+ 7% lard). When the animals reached 60 kg body weight each group was halved. One half had free access to the above rations, while the other half were fed ad libitum on the control ration. At body weights of 50 and 100 kg the concentrations of urea, insulin, glucose and cholesterol were measured, in addition the fatty acid composition of the backfat. At the end of the experiment (100 kg) the content of fat in the carcass was calculated by determining the specific gravidity of the carcass. There was little difference in the intake of metabolizable energy (ME) of the different groups of animals at both body weight ranges as a result of the reduction in feed intake of the fat supplemented diets on account of the higher ME-content. There were little differences in the glucose and urea concentrations in the blood of the animals fed the different rations. The highest cholesterol and the lowest insulin levels were measured in groups III and IV, when 5 and 7% lard was added, respectively. The animals, continuously fed Rations III and IV over the whole period of experiment, had a significantly higher fat content (p less than 0,05) than the control animals. There was a very marked influence of the fatty acid intake on the fatty acid pattern of the backfat. Following the change of feed to the control ration at 60 kg body weight, the linoleic acid content of the animals in Groups III and IV was significantly reduced (p less than 0,001) from 15.7 to 11.2%. However this was higher than the 7.3% linoleic acid measured on the animals continuously fed the control ration.

[Nutrition physiology effects of dietary fats in rations for growing pigs. 5. Effects of soy bean oil and lard on protein retention in piglets]

In two experiments with 30 and 26 castrated male pigs of the German Landrace breed, weight range 15-30 kg, the influence of isoenergetic changes in the carbohydrate and fat fractions of the diet were examined. The effect of the addition of soya oil (SO) and lard (LA) to the diet on the utilization of protein and on the blood urea concentration was also examined. The apparent digestibilities of the crude nutrients and energy were determined using different methods. The following were examined: experiment I: ration I (control), ration II (+7% SO), ration III (+7% LA) experiment II: ration I (control), ration II (+2% SO), ration III (+2% SO + 5% LA), ration IV (+7% LA) In all experiments the animals were fed a similar amount of digestible crude protein of constant quality at constant ME-intake. In both experiments the apparent digestibility of crude protein in the groups with 7% added fat was 4% higher (p less than 0,05) than in the corresponding control groups. The apparent digestibility of crude fat in experiment I and II (in groups II and III and in groups III and IV, respectively) was approximately 87%, when calculated on the basis of faecal fat which was determined by a simple ether extract procedure. When the faeces was treated with HCl before determination, these values for experiment I and II were approximately 6% (p less than 0,001) and 1% (NS) lower, respectively. In both experiments the utilization of protein and the blood urea concentration were not significantly influenced by the amount or form of fat included in the rations.

[Nutritional-physiological effects of dietary fats in rations for growing pigs. 4. Effects of sunflower oil and coconut oil on protein and fat retention, fatty acid pattern of back fat and blood parameters in piglets]

Rations containing 12% sunflower oil (Ration II) and 12% coconut fat (Ration III) were compared with a control ration (Ration I) in a 34 day experiment with growing boars of the German Landrace breed (12-30 kg body weight). The relationships between DP and ME were held constant for all 3 rations, and because of the higher ME contents of the two fat rations, this was achieved by reducing the feed intake, relative to that of the control ration. Parameters measured were growth, composition at slaughter, the apparent digestibility of the crude nutrients and energy, the N-balance and the concentrations of urea, insulin, glucose, triglyceride and cholesterol in the blood. In comparison to Ration I, the apparent digestibilities of crude protein in Rations II and III were 5 and 4% (p less than 0,05) higher, respectively. There was little difference in the apparent digestibility of crude fat between the Rations II and III. However, large differences in the values were determined depending upon method of extraction. There were little differences in the productive performance of the animals fed the fat diets. The control animals had, however, a 13% lower growth rate (p less than 0,05) when compared at similar ME-intakes. As the energy concentration and the growth rate were higher in groups II and III, the feed conversion efficiency and the ME required per kg growth were approximately 30 and 13% lower than that of the control animals. The efficiency of protein utilization of the animals in group III was 4% higher (p greater than 0.05) and the blood urea concentration 20% lower (p less than 0.05) than that in group II. The values for the control animals were intermediate. A similar result was obtained concerning the fat content of the animals. The fat content of the animals in group III was 15.9% and this was significantly lower (p less than 0.001) than that of 21.1% measured in group II. That of the control animals, 18.6%, was not significantly different from the above values. The differences in feeding over the relatively short period of 34 days lead to marked differences in the fatty acid pattern of the backfat. The contents of myristic acid and linoleic acid were significantly different between group II and III; for the former values of 0.8% and 16.9% were determined, respectively, with corresponding values of 48.7 and 11.3% for the latter.(ABSTRACT TRUNCATED AT 400 WORDS)

[Nutritive physiological effect of dietary fats in growing swine rations. 3. Effect of sunflower and coconut kernels on protein and fat retention, backfat fatty acid pattern and various blood parameters in piglets]

Two groups, each of 9 castrated male piglets of the German Landrace breed, body weight 13-29 kg, were fed ad libitum for a 5 week period in order to determine the influence of the fatty acid composition of the dietary fat on protein and fat retention. The concentrations of urea, insulin, glucose, free glycerol and triglycerides were also determined. That fat in ration I (derived from 27% sunflower seed) contained 50% linoleic acid while that of ration II (derived from 12,5% coconut kernels) had a maximum lauric acid content of 41,8%. The relationship between digestible crude protein and ME-content was calculated to be similar in both rations. In addition protein quality was calculated to be similar in both rations. Protein deposition was determined from both nitrogen and comparative slaughter procedures. The results can be summarized as follows: The animals fed ration I had a higher daily ME-intake and growth rate than those fed ration II, although no great difference was observed in ME required per kg body weight gain. The efficiency of protein utilization was significantly better in group I and this was associated with a lower blood urea concentration. The concentrations of insulin and glucose in the blood, measured before as well as 20, 45, 60 and 120 minutes following feeding, showed little differences between the groups. The triglyceride concentration measured before and 1 and 5 hours following feeding was significantly higher (p less than 0,01) in group II. There was no significant difference in the protein and fat content of the body as well as in the daily protein and fat deposition. The fatty acid composition of the back fat was significantly influenced by the fatty acid pattern of the dietary fat. In group I the linoleic acid content was 3,6 times higher and the lauric- and myristic acid content 11,7 times lower compared to that of group II.

[Nutritive physiological effect of dietary fats in rations for growing swine. 2. Effect of an isocaloric exchange of carbohydrate energy versus fat energy in piglets on growth and various metabolic parameters in the subsequent fattening period]

The influence of different feeding regimes of piglets on fattening performance and blood composition of the subsequent fattening period (30-100 kg) was examined. Three groups of pigs fed on an isocaloric and isonitrogenous basis with rations containing either 5% fat (groups I), 18% fat (group II) or 35% fat (group III) until body weight of 30 kg, were fed ad libitum one diet from 30 kg onwards. At a body weight of 45 and 93 kg the blood concentrations of insulin, glucose, urea, free fatty acids, neutral lipids and cholesterol in response to feeding and of insulin and glucose in response to an oral glucose load was determined in pigs provided with a permanent jugular vein catheter. Moreover, the in-vitro fat synthesis from glucose was measured. At the end of the experiment the body composition was determined by chemical analysis of the carcass. Neither feed intake, daily body weight gain nor feed conversion differed significantly among the groups. Blood urea levels of the three groups did not suggest a different protein utilization. Neither feed consumption nor oral intake of glucose affected the insulin and glucose response of the three groups differently. The concentrations of free fatty acids, neutral lipids and cholesterol did not differ clearly among the groups although occasionally significance of difference was observed. In group I the in-vitro synthesis of fat was increased (p less than 0.05) at a body weight of 45 kg and appeared to be higher at a body weight of 93 kg as compared to the high fat group (group III). No clear differences between the groups were observed in the chemical composition of the carcasses. It is concluded, that isocaloric replacement of carbohydrates by fat in the diet of piglets does not affect protein and fat retention in the subsequent fattening period.