Effect of vitamin E and fat source in sows' diets on immune response of suckling and weaned piglets

Thirty-six 7-mo-old gilts were used to study the effects of dietary vitamin E and fat source (5% sunflower oil or animal fat) in pregnant and lactating sow diets on serum vitamin E concentration and on cell-mediated and humoral immune response in suckling and weaned piglets. Six gilts each received one of six diets throughout pregnancy and lactation. The basal diets (13 mg alpha-tocopherol/kg diet) were supplemented with dl-alpha-tocopheryl acetate to 48 and 136 mg alpha-tocopherol/kg of feed (average analyzed values). After weaning (at 4 wk of age) all pigs received identical diets (20 mg of alpha-tocopherol/kg feed). One week after weaning, pigs were immunized (i.m. with ovalbumin and tetanus toxoid) and antibody production was measured. Blood samples were taken immediately after birth, at 1 wk after birth, at weaning, and at four weekly intervals after weaning. Samples were analyzed for alpha-tocopherol concentration, total number of leukocytes, T- and B-lymphocytes, lymphocyte stimulation with concanavalin A, lysozyme activity, and immunoglobulin concentrations. It was concluded that a high vitamin E level in the sow's diet increased serum vitamin E concentration of 1-wk-old pigs (P less than .05). Immune response against ovalbumin was increased (P less than .05) at 1 wk of age after immunization for weaned pigs from sows fed the high level of vitamin E. Also, the phagocytic measures of pigs at 1 wk of age were increased by the medium vitamin E level (P less than .05). Fat sources in the sow's diet had no consistent effect on the immunological measures of pigs.     

Effect of dietary calcium level and source on mineral utilisation by piglets fed diets containing exogenous phytase

Calcium and phosphorus are essential minerals, closely linked in digestive processes and metabolism. With widespread use of low P diets containing exogenous phytase, the optimal dietary Ca level was verified. The 40‐day study evaluated the effects of Ca level (4, 7 and 10 g/kg diet) and Ca source (Ca from CaCO₃ and from Lithothamnium calcareum) on mineral utilisation in 72 piglets (7.9 ± 1.0 kg BW) fed an exogenous phytase containing diet with 2.9 g digestible P/kg. Measured parameters were growth performance, stomach mineral solubility, bone breaking strength and urinary, serum and bone mineral concentration. The apparent total tract digestibility of minerals was also assessed in the two diets with 7 g Ca/kg, using 12 additional pigs. Regardless of Ca source, increasing dietary Ca impaired feed conversion ratio, increased urinary pH, increased serum and urinary Ca, decreased serum and urinary P, decreased serum Mg and increased urinary Mg, increased serum AP activity, decreased bone Mg increased bone Zn. Bone breaking strength was improved with 7 compared to 4 g Ca/kg. Compared to CaCO₃, Ca from Lithothamnium calcareum increased serum Mg and with, 10 g Ca/kg, it limited body weight gain. The dose response of Ca in a diet with 2.9 g digestible P/kg and including exogenous phytase indicated that: (i) a low dietary Ca was beneficial for piglet growth, but was limiting the metabolic use of P; (ii) a high dietary Ca level impaired P utilisation; (iii) the optimal P utilisation and bone breaking strength was obtained with a dietary Ca‐to‐digestible P ratio of 2.1 to 2.4:1; (iv). Increasing dietary Ca reduced Mg utilisation, but not Zn status, when fed at adequate level. Finally, Ca from Lithothamnium calcareum had similar effects on Ca and P metabolism as CaCO₃, but impaired growth when fed at the highest inclusion level.     

不同纤维来源与添加水平对断奶仔猪生长性能的影响

试验研究不同纤维来源与不同添加水平对断奶仔猪生长性能的影响。选用21日龄断奶三元杂交(杜长大)仔猪245头,初始平均体重为(6.44±0.09) kg,采用完全随机区组分为5个处理:①对照组;②0.5%小麦麸组;③1%小麦麸组;④1%燕麦糠壳组;⑤2%燕麦糠壳组。每个处理7个重复,每个重复7头猪,试验期21 d,对照组为玉米-豆粕型日粮,中性洗涤纤维(neutral detergent fiber,NDF)水平为5.92%,纤维组直接用纤维原料替代玉米,日粮NDF水平增至7.3%,所有处理组日粮粗蛋白质(crude protein,CP)含量近乎一致。结果表明,纤维组没有降低仔猪生长性能,且断奶后第一周1%麦麸组和1%燕麦糠壳组平均日增重显著高于对照组(P0.05),且2%燕麦糠壳组仔猪平均日增重极显著高于对照组(P0.01)。断奶后第2周1%和2%燕麦糠壳组仔猪平均日增重仍显著高于对照组(P0.05),但第2周平均日采食量并无显著提高(P0.05),直接原因是断奶第2周料重比显著低于其他组(P0.05)。断奶后第3周各处理组间平均日采食量、平均日增重和料重比差异不显著(P0.05),但数据上看纤维组好于对照组。不同处理组粪便评分差异不明显,但2%燕麦壳组腹泻率显著降低(P0.05)。综上所述,以不同纤维源及纤维组分配制的日粮对断奶仔猪生产性能和肠道健康有不同影响。其中日粮中加入2%的燕麦糠壳效果优于其他处理组。     

Effects of growth hormone administration on vitamin D metabolism and vitamin D receptors in the pig

Twelve 36-kg pigs were given either 100 micrograms/kg porcine pituitary growth hormone (pGH) or placebo injections daily for 33 days. Serum was obtained weekly for analysis of minerals and vitamin D metabolites. On day 34, the pigs were sacrificed and renal and duodenal tissue were obtained for analysis of vitamin D receptor content (VDR). Animals treated with pGH grew faster and had a higher rate of bone accretion than did control animals. Serum concentrations of 1,25-dihydroxyvitamin D (1,25-(OH)2D) were significantly higher in pGH-treated pigs than in control pigs at all time points following initiation of treatment, with the greatest difference observed at day 28 (42.4 +/- 4.9 pg/ml in controls vs. 65.4 +/- 4.7 pg/ml in pGH-treated pigs). Serum 24,25-dihydroxy-vitamin D tended to be lower in pGH-treated pigs than in control pigs, being significantly lower on day 21 of the experiment (3.22 +/- .52 vs. 6.73 +/- 1.22 ng/ml, respectively). Serum concentrations of 25-hydroxyvitamin D and calcium were unaffected by pGH treatment. Kidneys of control pigs contained significantly more unoccupied vitamin D receptors than did kidneys from pGH-treated pigs (73.3 +/- 4.3 vs. 58.3 +/- 4.1 fmoles/mg protein). Duodenal tissue unoccupied vitamin D receptor content was similar in both pGH-treated (245 +/- 17.9 fmoles/mg protein) and control (263 +/- 21.8 fmoles/mg protein) pigs. Duodenal occupied vitamin D receptor concentration was similar in both pGH-treated (6.8 +/- .75 fmoles/mg protein) and control pigs (5.32 +/- .77 fmoles/mg protein).(ABSTRACT TRUNCATED AT 250 WORDS)     

日粮由添加甘露寡糖和香精油对仔猪生长性能的影响

本试验目的是研究日粮中添加甘露寡糖和香精油替代抗生素对仔猪生产指标的影响.25窝个体均匀的仔猪被随机分配到5个试验组中,每组50～60只.仔猪在30日龄断奶,在仔猪断奶前2d开始给仔猪饲喂教槽料,并持续饲喂39d.试验组(Ⅰ组)仔猪采食的日粮不含抗生素,试验组(Ⅱ组)仔猪采食含抗生素多黏菌素E(120mg/kg)的日粮,试验组(Ⅲ、Ⅳ、Ⅴ组)仔猪采食含添加剂(甘露寡糖和香精油)的日粮,其中,断奶前每吨日粮中分别添加4、5和6kg的添加剂(甘露寡糖和香精油),断奶后每吨日粮中分别添加2、3和4kg的添加剂(甘露寡糖和香精油).在整个试验阶段对试验仔猪的体重、日增重、采食量和饲料转化率等指标进行了测定,并着重观测了仔猪的健康状况和死亡率等指标.本试验结果表明,当日粮中不添加抗生素时,哺乳仔猪的生产指标显著下降.日粮中添加4kg/t的甘露寡糖和香精油来替代抗生素时能相对保持仔猪的体重和日增重,并能降低哺乳仔猪的死亡率.     

Effects of dietary calcium content and vitamin D source on skeletal properties in growing turkeys

1. The aim of the study was to investigate the effects of feeding fast growing turkeys with differentiated dietary calcium (Ca) content, and the partial replacement of vitamin D₃ in the feed with 25-hydroxycholecalciferol (25(OH)D₃), on skeletal properties.

2. One-day-old Big-6 male turkeys (n?=?1008) were randomly divided into 4 groups, and two subgroups were created within each group. The groups were differentiated with 4 levels of Ca provision in the feed, namely 85% of the National Research Council (NRC) recommendation (Group Ca₁); 95% as above (Group Ca₂); 105% as above (Group Ca₃); and 115% as above (Group Ca₄). The first subgroup received the recommended dosage of cholecalciferol (vitamin D₃ subgroup) in the feed, while in the second subgroup (Hy-D subgroup), half of the dosage of cholecalciferol was replaced with 25(OH)D₃. At the ages of 4, 8, 12 and 20 weeks, 7 turkeys from each subgroup were randomly selected and killed to obtain the right tibia for densitometric, geometric and mechanical analyses.

3. This study showed advantageous effects of increased calcium supply in the diet on skeletal system properties, that were increased and produced the most desirable traits in turkeys receiving 95%, 105% and 115% of the NRC calcium recommendation. Benefits resulting from administration of 25(OH)D₃ in the diet were also obtained in the skeletal formation of turkeys, and the most advantageous effects were present in the group receiving 105% of recommended dietary Ca.

4. Effects on the metabolic response of the skeleton of turkeys to manipulation of dietary calcium content and vitamin D₃ source were the most evident in the groups between 4 and 12 weeks of life, and demonstrated a limited ability to induce a positive influence on bone properties at advanced stages of the production cycle by alteration of these dietary factors.     

日粮添加牛油对断奶仔猪生产性能和血清皮质醇的影响

为了探讨日粮添加牛油对断奶仔猪物生产性能及内分泌功能的影响,试验选取平均体重(5.02±0.45)kg、(21±3)日龄的三元仔猪36头,随机分为3组,基础日粮对照组(含1.5%牛油)和3%、6%牛油日粮,每组2个重复,每个重复6头,试验期21 d。结果表明:添加3%牛油组显著提高了仔猪的平均日增重(ADG)、降低了料重比(P0.05),而添加6%牛油组与对照组比较差异未达显著水平(P0.05);皮质醇的浓度随着添加牛油的浓度提高和时间的延长有上升的趋势,6%牛油组显著升高(P0.05);仔猪血液中的总胆固醇(TC)、甘油三脂(TG)浓度随牛油浓度增加而升高;添加牛油显著提高了十二指肠内容物中脂肪酶的活性(P0.05),但对蛋白酶活性无显著影响(P0.05)。     

The effect of maternal vitamin D source on broiler hatching egg quality,hatchability, and progeny bone mineral density and performance

Vitamin D is involved in calcium metabolism as well as bone and shell quality, and is therefore important to broiler breeders. In this research we investigated the effects of maternal dietary 25-OH vitamin D₃ on broiler breeder egg quality and hatchability, as well as on progeny bone mineral density and performance. In a field study, all hens were fed 3,000 IU of vitamin D₃ (D) per kilogram of complete feed; in addition half of the hens also received 34.5 µg of 25-OH vitamin D₃ per liter in the drinking water (25OHD). Eggs from each treatment group were incubated and hatched; chicks were fed a common diet and grown to 41 d of age. Eggs from hens in the 25OHD treatment had a nearly 30% reduction in early embryo mortality. However, a larger egg size resulted in greater chick BW for the D chicks, although this did not affect broiler production performance. Broilers from the maternal 25OHD treatment had a lower FCR during the grower phase. Unexpectedly, chick plasma 25-OH vitamin D₃ was only greater for the maternal 25OHD treatment at 4 d of age, but not at hatch, 2, 6, 8, 10, 12, or 14 d of age. Maternal vitamin D₃ source did not affect progeny 41-d bone mineral density. Maternal 25-OH vitamin D₃ had a protective effect on the growing embryo, reducing early embryonic mortality, with minimal effects on progeny performance and bone mineral density to processing at 41 d of age. The previously reported effects of 25-OH vitamin D₃ on increasing broiler performance and breast yield seem to be dependent on supplementation of the broiler diet; a carry-over effect of maternal supplementation is insufficient to achieve these effects.     

Effects of 25‐hydroxycholecalciferol supplementation in maternal diets on milk quality and serum bone status markers of sows and bone quality of piglets

Twenty primiparous sows were allocated to two treatments to evaluate the effects of maternal 25‐hydroxycholecalciferol (25OHD₃) supplementation during gestation and lactation on milk quality and serum bone status markers of sows and bone quality of piglets. Immediately after mating, sows were randomly allotted to one of two diets supplemented with 50 µg/kg 25OHD₃ or basal diets without 25OHD₃. Blood and milk samples were obtained. At birth and weaning, 10 piglets from each treatment were killed for bone quality analysis. 25OHD₃‐fed sows provided one more piglet at farrowing and 1.17 more piglets at weaning than sows fed basal diets. The contents of solids not‐fat, protein, fat or lactose were increased in milk from days 7 and 14 of lactation in 25OHD₃‐supplemented sows and 25OHD₃ concentrations in milk were increased by dietary 25OHD₃ supplementation. Dietary 25OHD₃ supplementation increased serum alkaline phosphatase activity but had no effect on serum tartrate‐resistant acid phosphatase activity of sows. Maternal 25OHD₃ supplementation improved bone strength, density and ash content of newborn piglets rather than those of weaning piglets. In conclusion, 25OHD₃ supplementation in maternal diets improved reproductive performance, milk quality and bone status of sows as well as bone quality of newborn piglets.     

寡果糖对断奶仔猪生长、代谢和免疫的影响

在基础日粮中添加寡果糖 ,研究其对断奶仔猪生长、代谢和免疫的影响。试验将 32头杜大二断奶仔猪分为 2组 ,基础日粮为对照组 ,基础日粮添加 0 1 7%寡果糖为试验组 ,预试期 4d ,正式试验期 2 8d。结果表明 :试验组较对照组仔猪日增重提高 3 88% (P >0 0 5) ,料重比下降4 67% ;仔猪血液尿素氮含量显著升高 (P<0 0 1 ) ,甲状腺素 (T4)和白细胞介素 2 (IL 2 )含量也显著升高 (P<0 0 5) ,血糖和T3含量有升高趋势 ,但不显著     

Dietary phosphorus restriction affects bone metabolism,vitamin D metabolism and rumen fermentation traits in sheep

Homeostasis of calcium (Ca) and phosphate (P_i) is maintained by a concerted interplay of absorption and reabsorption via the gastrointestinal tract and the kidney and by storage and mobilization from the bone regulated mainly by parathyroid hormone (PTH), 1,25-dihydroxycholecalciferol and calcitonin. The present study aimed at characterizing the effects of dietary P restriction on bone, vitamin D metabolism and rumen fermentation traits reflecting the endogenous P cycle maintaining the ruminal P supply for microbial metabolism. The experiments were done in eleven female, non-pregnant, non-lactating four- to nine-year-old Black Headed Mutton sheep allotted to two feeding groups: "P-restricted" (0.11% P/kg DM and 0.88% Ca/kg DM) and "Control" (0.38% P/kg DM and 0.88% Ca/kg DM). Dietary P restriction did not lead to hypophosphataemia, probably due to a compensation by bone mobilization, demonstrated by increased serum concentrations of a resorption marker and altered gene expression in bone tissue. In addition, the RNA expression of fibroblast growth factor 23, a bone-derived factor involved in the regulation of vitamin D metabolism, was significantly reduced with dietary P restriction. Furthermore, several genes related to vitamin D metabolism and plasma concentrations of 1,25-(OH)₂D were associated with serum concentrations of phosphate (P_i). In the parotid gland, the expression of the P_i transporter NaPi2b was negatively associated with serum P_i and positively with parathyroid PTH expression. Although P_i concentrations in saliva and the gastrointestinal tract were significantly reduced, we found no adverse effects of the P-restricted ration on the production of short chain fatty acids, but slight differences in the production of butyrate as well as its relationship to rumen P_i and ammonia concentrations that might indicate an impact on ruminal fermentation.     

Effect of creep partitions on teat-seeking behavior of newborn piglets

In the first of two studies on teat-seeking behavior of newborn pigs, latencies from birth to first mammary contact (LMC) and to first suckle (LS) were recorded by live observation (n = 66). LMC accounted for 66% of LS and variances were similar between these two measures, suggesting that LMC is a good predictor of time to first suckle. In a second experiment, 32 litters of pigs were farrowed in crates equipped with either solid, vertically slatted, horizontally slatted or diamond mesh creep partitions. Piglet behavior following parturition was recorded via time-lapse videotape. LMC was determined for each piglet and movements were plotted for four focal pigs/litter. Partition type did not affect LMC (mean = 34 min). LMC was significantly affected by number of littermates present during teat-seeking (P less than .001), birth order (P less than .001) and frequency of position changes by the sow (r = .26, P less than .01). Neither sex nor birth weight affected LMC on a within-litter basis, but across litters smaller pigs had greater contact latencies (r = -.38, P less than .001). Partition type did not affect distance traveled or time spent in contact with the sow, in contact with the creep partitions,, free standing or the total of these. LMC was positively correlated (P less than .05) with contact time with the sow (r = .34) and time behind the sow's back (r = .38) and negatively correlated with time spent free standing (r = -.35, P less than .05) and in contact with the sow's rear legs (r = -.29; P less than .10).     

大豆黄酮对产蛋鸡蛋壳品质和骨骼代谢的影响

大豆黄酮(Daidzein)属于异黄酮类植物雌激素(Isoflavonic phytoestrogen),主要存在于豆科的蝶形花亚科植物中。20世纪90年代以来,国外流行病因学研究证明,膳食中的异黄酮具有防癌和抗癌的作用,使人类乳腺癌、结肠癌发病率降低,近年来动物营养研究表明大豆黄酮具有促进动物生长,增加产     

Effects of dietary dihydroartemisinin supplementation on growth performance,hepatic inflammation,and lipid metabolism in weaned piglets with intrauterine growth retardation

The aims of this study were to investigate the effects of dietary supplementation with dihydroartemisinin (DHA) on growth performance, hepatic inflammation, and lipid metabolism in intrauterine growth retardation (IUGR)‐affected weaned piglets. Eight piglets with normal birth weight (NBW) and 16 IUGR‐affected piglets were selected and fed either a basal diet (NBW and IUGR groups) or the basal diet supplemented with 80 mg/kg DHA (IUGR‐DHA group) from 21 to 49 day of age. Blood and liver samples were collected on day 49. DHA supplementation significantly alleviated the compromised growth performance and liver damage in IUGR‐affected piglets. Additionally, DHA supplementation decreased the activities of alanine aminotransferase and aspartate aminotransferase, as well as the serum levels of non‐esterified fatty acids (NEFA), very‐low‐density lipoprotein, and total cholesterol. In the liver, the concentrations of interleukin 1 beta, interleukin 6, tumor necrosis factor alpha, triglycerides, and NEFA were decreased. Fatty acid synthesis was decreased by DHA supplementation, whereas the activities of lipoprotein lipase, hepatic lipase, and total lipase were increased. Dietary DHA supplementation led to upregulation of the expression of AMPK/SIRT1 signaling pathway‐related genes, whereas that of inflammatory factor‐related genes were downregulated. In conclusion, dietary inclusion of 80 mg/kg DHA can alleviate IUGR‐induced impairments in piglets.     

Effect of dietary boron on growth performance, calcium and phosphorus metabolism, and bone mechanical properties in growing barrows.

An experiment was conducted to evaluate the effects of dietary boron (B) on growth performance, bone mechanical properties, and calcium (Ca) and phosphorus (P) metabolism in pigs. Thirty-six barrows were weaned at approximately 21 d of age and randomly assigned to receive one of three dietary treatments. Treatments consisted of 1) low-B basal diet (control), 2) basal + 5 mg B/kg diet, and 3) basal + 15 mg B/kg diet. Boron was supplemented as sodium borate. Barrows remained on their respective experimental diets throughout the nursery (35 d) and growing (30 d) phases of production. Blood samples were obtained from each barrow at the end of each phase. Following the 30-d growing period, eight barrows per treatment were transferred to stainless steel metabolism crates. Barrows had an adjustment period of 7 d, followed by a 7-d total collection of urine and feces. All barrows were fed at 90% of the previous ad libitum grower intake of the control animals during the adjustment and collection periods. At the end of the 7-d collection period, barrows were killed and femurs and fibulas were harvested for the assessment of bone mechanical properties. During the nursery phase, ADG and ADFI were increased (P < 0.05) by B supplementation. Boron did not affect (P = 0.34) feed efficiency during the nursery phase. During the growing phase, ADG and ADFI were increased (P < 0.05) by B supplementation. Boron did not affect (P = 0.97) feed efficiency during the growing phase. Boron did not affect (P = 0.44) bone ash percentage, but B supplementation increased (P < 0.05) bone ash P. Ultimate shear force of the fibula was increased (P < 0.05) in barrows supplemented with 15 mg B/kg diet compared to barrows fed diets supplemented with 5 mg B/kg diet. Apparent absorption and retention of Ca and P were not affected (P > 0.05) by dietary B. These data indicate that B supplementation to pigs can increase growth and bone strength without greatly affecting Ca and P metabolism.     

Influence of level and source of dietary fat on its comparative feeding value in finishing diets for feedlot steers: metabolism

Six crossbred steers (315 kg) with cannulas in the rumen, proximal duodenum and distal ileum were used to study the influence of level and source of dietary fat on characteristics of digestion. Dietary treatments consisted of a steam-rolled barley-based finishing diet containing 1) no supplemental fat; 2) 4% yellow grease (YG); 3) 4% blended animal-vegetable fat (BVF); 4)8% YG; 5) 8% BVF or 6) 6% BVF and 2% crude lecithin. Increasing level of fat supplementation resulted in linear decreases (P less than .01) in ruminal and total tract digestion of OM and ADF and intestinal digestion of fat (P less than .05). At the 4 and 8% levels of supplementation, intestinal true digestibility of fat averaged 80.1 and 69.3%, respectively. Ruminal molar proportions of acetate decreased, and propionate molar proportion, as well as DE and ME values of the diet, increased linearly (P less than .01) with level of fat supplementation. The DE and ME values for fat were 8.17 and 9.76 at the 4% level and 7.35 and 8.72 Mcal/kg at the 8% level of supplementation, respectively. Yellow grease supplementation resulted in greater (P less than .05) ruminal fiber digestion and greater ruminal molar proportions of propionate than BVF. Intestinal fat digestion was similar (P greater than .10) for YG and BVF. Adding 25% lecithin to BVF resulted in greater ruminal fiber digestion and greater ruminal molar proportions of acetate; however, lecithin tended (P less than .10) to have a lower ME value than BVF.     

高纤维日粮对仔猪营养性腹泻及生产性能的影响

选取57头“长白×施格”杂交仔猪作为试验动物,研究提高日粮纤维含量对于仔猪营养性腹泻和生产性能的影响。结果表明,使用苜蓿草粉作为主要纤维源,将仔猪日粮中粗纤维含量由2.8%提高到5.3%,对于仔猪的日增重、日采食量和饲料转化率没有产生不利的影响,能有效地防止仔猪腹泻,在断奶后1周内极显著地提高了仔猪增重(P<0.01)。     

不同能量饲粮添加植酸酶对杂交仔猪生长性能影响的研究

选用48头长白×荣昌杂交仔猪进行2个2×2因子的生长试验,试验期2周,每个试验均设2个有效磷水平(0.36%、0.26%)、2个植酸酶添加水平(0、750FTU/kg),共4个处理组,每个处理组设6个重复,每个重复1头仔猪。试验1为高能水平(DE:14.27MJ/kg),试验2为低能水平(DE:12.8MJ/kg)。结果表明:在试验1饲粮中添加植酸酶,仔猪平均日增重(ADG)、增重/代谢体重(GPW)、G/F分别提高8.1%、6.4%、3.6%;每千克增重的饲粮成本(CPG)降低3.1%;降低饲粮有效磷水平后,ADG、GPW、G/F分别降低1.5%、6.1%、3.5%;CPG增加0.4%(P>0.05)。在试验2饲粮中添加植酸酶,仔猪ADG、GPW、G/F、分别提高10.6%、7.2%、7.9%;每千克增重的饲粮成本(CPG)降低6.6%;降低饲粮有效磷水平后,ADG、GPW、G/F分别降低3.8%、3.3%、3.2%;CPG增加3.0%(P>0.05)。由此表明,在本试验条件下,饲粮中添加植酸酶能够提高仔猪的生长性能,降低仔猪生长的饲粮成本。     

Spray-dried plasma in diets for weaned piglets: influence on growth and underlying mechanisms

Spray-dried animal plasma (SDAP) is a by-product of slaughter plants. The plasma obtained from slaughtered pigs or ruminants is spray-dried and used for the production of human foodstuffs and animal feeds. SDAP added to the diet of weaned piglets has considerable positive effects on the growth performance of piglets. In a meta-analysis, it was calculated from 68 comparisons between SDAP-containing diets and control diets that the SDAP-induced change in average daily gain (ADG) and average daily feed intake (ADFI) in the first 2 weeks after weaning was +26.8% and +24.5%, respectively. Two experiments demonstrated that dietary SDAP can reduce post-weaning diarrhoea. The aim of the research described in this thesis was to learn more about the mechanisms underlying the growth- and health-promoting properties of SDAP in the diet of weaned piglets. Results showed that dietary SDPP has positive effects on the post-weaning growth performance and health of piglets. These effects are more pronounced in piglets kept under suboptimal conditions and/or high infection pressure, and in piglets fed on diets lacking anti-microbial growth promoters. SDAP acts by influencing the gastrointestinal microflora: it appears to affect pathogenic bacteria rather than exert a general anti-bacterial effect leading to nutrient sparing, as has been described for anti-microbial growth promoters. SDAP has great potential as treatment for immuno-compromised mammals, such as neonates, and for animals in which antibiotic treatment is not possible, for instance when there is a ban against antibiotics or when multi-resistant bacteria are involved.