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.     

Effects of feeding aspirin and soybean oil to weanling pigs

Three trials were conducted with 216 Yorkshire x Duroc x Hampshire crossbred pigs (equal males and females) weaned at 3 to 4 wk of age (avg 7.4 kg initially) to determine the effectiveness of aspirin in an 18% CP corn-soybean meal starter diet (with and without soybean oil in Trial III) for improving postweaning performance and reducing scours. When aspirin levels common to all trials (0, 250 ppm) or common to Trials II and III (0, 125 and 250 ppm) were compared, improvements in ADG (P less than .10) and daily feed intake (P less than .05) were observed with no effect on efficiency of feed utilization. There was a quadratic effect of aspirin (P less than .10) in Trials II and III, the trend suggesting that the response to 125 ppm was as effective as the response to 250 ppm aspirin. The addition of soybean oil in Trial III did not enhance the response. In all trials, scouring was reduced (P less than .05) when pigs were fed 125 or 250 ppm aspirin; the improvement was greatest for 125 ppm aspirin after 5 d on test. Pooled data suggested no effect (P greater than .10) of aspirin on hemoglobin concentrations and blood clotting times; slightly higher (P less than .10) hematocrit values and DM content of colon digesta occurred in pigs fed 125 ppm aspirin vs controls.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ultrastructural alterations of the myocardium of rats fed rapeseed oils.

Ultrastructural studies were conducted on the myocardium of rats fed corn oil, Tower RSO (0 . 88 per cent EA), 1788 RSO (3 . 6 per cent EA) and Target RSO (38 . 9 per cent EA) supplemented diets for 18 weeks. Cardiac myocytes of Tower RSO-fed rats showed some loosening of myofibrils and a slight increase in the number of mitochondria, few of which had lost their cristae. Large intravascular lipid droplets were observed in the myocardium of rats fed the 1788 RSO diet, as well as some small lipid droplets which were seen in close association with mitochondria. There was an apparent increase in the number of mitochondria of both normal and giant size. Many of the mitochondria exhibited distortion of shape and degeneration of cristae. The matrix of megamitochondria contained vesicles and electron-dense floccular inclusions and at times electron-lucent lipid-like material. The degenerative changes of mitochondria were most pronounced in the Target RSO group, where some megamitochondria showed a complete loss of cristae and a replacement of matrix with lipid-like material. These observations suggest that both intravascular lipid globules and the mitochondrial alterations are possible contributory factors involved in the development of cardiac lesions in RSO-fed rats.     

Pathological changes in chickens, ducks and turkeys fed high levels of rapeseed oil.

Rations containing 25% of either regular rapeseed oil (36% erucic acid), Oro rapeseed oil (1.9% erucic acid), soybean oil or a mixture of lard and corn oil were fed to chickens, ducks and turkeys. The regular rapeseed oil ration caused growth depression, increased feed conversion and anemia in all species. All the ducks and some of the chickens fed the regular rapeseed oil ration died. These dead birds were affected with hydropericardium and ascites. No deaths in the turkeys could be attributed to the regular rapeseed oil ration but some turkeys fed this ration had degenerative foci characterized by infiltrations of histiocytic and giant cells in the myocardium. Severe fatty change in the heart, skeletal muscles, spleen and kidney was found at an early age in all birds fed the regular rapeseed oil ration. Less severe fatty change but no other lesions were found in birds fed the Oro rapeseed oil and soybean oil rations.     

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.     

Effects of feeding sunflower oil or seal blubber oil to horses with recurrent airway obstruction

A crossover feeding trial was performed with 9 horses suffering from recurrent airway obstruction (RAO). The study aimed to determine whether ingestion of sunflower oil (SFO), rich in linoleic acid, or seal blubber oil (SBO), a source of long-chain omega-3 polyunsaturated fatty acids (LC n-3 PUFAs), changes the fatty acid (FA) ratios in plasma and leukocyte membrane phospholipids (PLs) or the leukocyte numbers or proportions of cell types in the airways. We also investigated diet-related changes in respiratory rate, maximum change in pleural pressure (deltaPpl(max)), dynamic compliance (C(dyn)), and pulmonary resistance (RL). Each animal was fed hay and oats supplemented with 320 mg/kg body weight (BW) of either SFO or SBO for 10 wk. Before and after the feeding periods, we performed FA analyses, cytologic testing of the pulmonary epithelial lining fluid (PELF), clinical scoring, and pulmonary function testing. The results demonstrated that supplementary FAs were readily ingested and incorporated into leukocyte cell membranes. The n-6:n-3 FA ratios in plasma and leukocyte PLs were reduced after SBO supplementation, as were the PELF leukocyte counts (P < 0.05). On the other hand, pulmonary function and clinical signs were not markedly changed by the different dietary FAs. These results indicate a possible influence of dietary n-3 PUFAs on the pulmonary inflammation of horses with RAO. Further studies are warranted to address effects on inflammatory mediators and clinical outcome.     

Some effects of feeding lathyrogens to laying fowls

The lathyrogen semicarbazide inhibited egg‐laying in fowls. The primary target of the drug appeared to be the pituitary gland. Ovulation and normal egg production were resumed soon after withdrawal. The eggs laid during administration appeared to be normal except that their shell membranes were heavier and less pigmented. Amino acid composition of the membranes from treated birds was normal, but they yielded more soluble hydroxyproline‐containing material when autoclaved for 5 h. Prolonged (20 h) autoclaving of membranes from both treated and control birds produced a soluble material very rich in hydroxyproline. Deprivation of dietary calcium did not influence the observed effects of semicarbazide. Plasma‐free hydroxyproline assays indicated that in laying birds semicarbazide produced labilisation of body collagen, but in pre‐laying birds it caused lack of appetite to the point of inanition.     

The effects of feeding milk to diarrheic calves supplemented with oral electrolytes.

The effects of feeding different levels of milk to diarrheic calves (n = 19) supplemented with oral electrolytes were investigated. In the early stages of the disease the calves were fed either enough milk to maintain normal growth in a healthy calf, one half that volume or no milk. The three groups were further subdivided according to whether or not the electrolyte solution contained bicarbonate. A full milk ration allowed uninterrupted weight gains of 1% body weight/day (p = 0.003), but caused greater inappetence (p = 0.003 to 0.037) at the beginning of the trial than lower levels of milk intake. Electrolyte solutions with bicarbonate reduced growth rates in milk fed calves (p = 0.014). The density of fat stores increased with the level of milk feeding (p = 0.04 to 0.053). The mitotic index of the duodenal mucosa increased with milk feeding (p = 0.08), indicating a superior mucosal regeneration potential. Thymic atrophy was pronounced in those calves fed no milk (p = 0.001). It was concluded that the continued feeding of milk to diarrheic calves was beneficial. Electrolyte solutions containing bicarbonate should be avoided when milk is fed to diarrheic calves.     

氧化油脂造成畜禽氧化应激的途径及缓解措施

油脂是畜禽饲料中的高能组分,但在储存、加工和饲喂过程中易发生氧化酸败。氧化油脂直接或间接地导致动物体内自由基积累和维生素E含量下降,从而使畜禽发生氧化应激。文中论述了氧化油脂造成畜禽氧化应激的主要途径,以及如何采取相应的措施缓解氧化油脂对畜禽造成的不利影响。     

日粮不同动植物油配比对黄羽肉鸡血清学指标和抗氧化特性的影响

试验选用25日龄黄羽肉公鸡1 600羽,随机分成5组,每组4个重复,日粮中添加由猪脂和大豆油组成的混合油脂,各处理组猪脂占混合油脂的比例分别为0(I组)、25%(II组)、50%(III组)、75%(IV组)和100%(V组),试验分前期(25～45日龄)和后期(46～65日龄)两个阶段,各阶段结束时屠宰取样,测定相关血清生理生化和抗氧化指标。结果发现:(1)45日龄黄公鸡血清尿素氮含量I组比V组显著提高79.97%(P0.05);碱性磷酸酶活性II组显著升高(P0.05)。65日龄时黄公鸡尿素氮含量各组差异不显著(P0.05);碱性磷酸酶活性III组、IV组显著降低(P0.05)。(2)45日龄黄公鸡血清中SOD活性IV组比I组高32.70%(P0.05),65日龄时各抗氧化指标各组差异不显著(P0.05)。总之,日粮中猪脂与大豆油的比例为1～3∶1时,对黄鸡肝胆系统功能、蛋白质代谢和抗氧化特性有一定的改善作用,且3∶1比1∶1更适宜,此时日粮中不饱和脂肪酸与饱和脂肪酸之比为1.60(25～45日龄)和1.58(46～65日龄)。     

Physiological effects of feeding high levels of magnesium to sheep

The effects of feeding high levels of Mg to sheep on animal health, nutrient digestibility, metabolism of macro-minerals, blood and tissue mineral concentrations and hematological and histological tissue changes were evaluated. Six lambs were allotted to each of four diets supplemented with MgO to attain .2, .6, 1.2 or 2.4% Mg. Total fecal and urinary collections were made for the initial 20 d and last 10 d of a 50 d study. Diarrhea was noted in lambs fed the two highest Mg levels. Apparent digestibility of DM, ADF and CP decreased linearly (P less than .01) with increasing Mg levels. Dietary Mg levels did not affect (P greater than .05) rectal temperature, respiration rate or pulse rate. Apparent absorption and retention of Mg (g/d) were lowest in lambs fed 2.4% Mg until 15 d on trial, after which values increased linearly (P less than .01) with dietary Mg. Phosphorus absorption and retention decreased linearly (P less than .01) with increasing Mg levels. Increasing dietary Mg resulted in a linear increase (P less than .01) in serum Mg and variable increases (P less than .05) in erythrocyte Mg. Serum Ca was decreased linearly (P less than .05) and quadratically (P less than .05) by added Mg during the d 1 to 30 and 40 to 50 periods, respectively. Serum inorganic P was elevated consistently in lambs fed 2.4% Mg. A linear response to increasing dietary Mg (P less than .05) occurred in the Mg content of liver, kidney, rib bone and femur bone. Dietary Mg did not alter (P greater than .05) other criteria.(ABSTRACT TRUNCATED AT 250 WORDS)     

Physiological and pathological effects of feeding high levels of magnesium to steers

The effects of feeding high levels of Mg were evaluated in a 130-d study with 24 steers. Six steers were allotted to each of four diets supplemented with MgO to attain .3, 1.4, 2.5 or 4.7% Mg, DM basis. Chromic oxide was used as digesta marker; fecal grab samples were collected once daily during nine consecutive 10-d periods. Steers fed 2.5 and 4.7% Mg refused some feed during the study, so their respective dietary Mg intakes were 2.4 and 3.7% (DM basis). Severe diarrhea and a lethargic appearance were observed in steers fed the two higher Mg levels. Fecal DM and apparent DM digestibility decreased linearly (P less than .01) with increased dietary Mg. Apparent Mg absorption (g/d) increased linearly (P les than .01) and apparent Ca and P absorption (g/d) decreased linearly (P less than .01) with addition of Mg to the diet. Increasing dietary Mg linearly elevated blood serum and erythrocyte Mg (P less than .01; P less than .05, respectively) and serum inorganic P (P less than .05) and linearly decreased serum Ca (P less than .01). Magnesium concentration in liver, kidney, skeletal muscle and rib-bone and P in skeletal muscle all increased linearly (P less than .05) with dietary Mg. Increasing dietary Mg in the steers caused a progressive degeneration of the stratified squamous epithelium of rumen papillae. A progressively more serious Mg toxicosis condition developed over time in steers fed diets containing 2.4 and 4.7% Mg.     

Effects of feeding Ascochyta-infected and normal lentils to rats (short-term study).

Weanling, female, Sprague-Dawley rats were fed diets containing either rat chow with no lentils, 80% normal lentils or 80% diseased lentils heavily infected with the fungus Ascochyta lentis. Body weight, feed consumption and clinical appearance were monitored over 90 days and blood samples were collected at the termination of the experiment. Weight gain and feed consumption were similar in the control group and the group fed diseased lentils. Weight gain was slightly depressed in the group fed normal lentils. These effects were attributed to the lentils being a poorer source of protein than the wheat, barley and soybean meal used in the control diet, but the protein content of the diseased lentils was higher than the normal lentils. Total white blood cell counts and lymphocyte counts were significantly depressed (P = 0.05) in the group fed the diseased lentil diet. Significant differences (P = 0.05) were found among groups in the ratios of liver, kidney and spleen weights to body weight.