Protein and amino acid metabolism in the digestive tract of growing bull calves. 5. The amino acid flow into the duodenum

The flow of the individual amino acids (AA) into the duodenum was determined after the feeding of 28 different rations to young bulls supplied with duodenal re-entrant cannulae in the live weight range between 140 and 460 kg. The distribution of AA into AA of bacterial origin and AA from the feed was made by difference calculation between the AA at the duodenum (corrected by the endogenous AA quota) and the AA from the bacteria crude protein, with our own results based on a constant AA composition of the bacteria crude protein; by the regression analysis from relative values according to AAD/app. dig. org. m. = a + b AAF/app. dig. org. m. and by the regression analysis of the absolute values according to AAD = b1 app. dig. org. m. + b2 AAF showed the same results from the regression methods but deviating ones from the difference method. The calculation of the flow of the individual AA into the duodenum from the AA content of the ration and the content of app. dig. org. m. of the ration is possible. The equations derived for this purpose of the individual AA are given.     

Protein and amino acid metabolism in the gastrointestinal tract of young bulls. 3. Flow of NH3-free raw protein into the duodenum

The amount of NH3-free crude protein getting into the duodenum corrected by the endogenous crude protein quota was determined on the basis of 28 differently composed rations for growing bulls in the live weight range of 140-460 kg provided with duodenal re-entrant cannulae. The experimental results were generalized by means of regression analysis and can be summarized as follows: The amount of NH3-free crude protein getting into the duodenum can partially be calculated with the regression equation (Formula: see text) resp. NH3-free crude protein D = 155 app. dig. org. matter + 0.262 pure protein +/- 42. The remaining dispersion amounts to +/- 6% of the mean value. The coincidence between the values calculated with these equations and those measured experimentally is very good. There is an interaction between the pure protein of feed getting into the duodenum in % of pure protein intake (y) and the bacteria crude protein D/kg app. dig. org. matter (x) characterized by the equation y = 116.8-0.52 x +/- 12.9. The amount of NH3-free crude protein duod. is not influenced by the flow rate (kg digesta/kg intake of org. matter) and not by the "dilution rate' (g bacteria free org. matter duod./kg live weight 0.75/h) either at a DM intake adequate to the production level. Apart from the partial estimation of the NH3-free crude protein duod. a evaluation based on the crude protein and pure protein concentration in app. dig. org. matter of the ration is possible.     

Performance of lactating sows in response to the dietary valine supply

In order to determine the requirement of lactating sows for valine (Val) the effects of graded Val supplementations on feed intake, milk yield and changes of body weight of sows and piglets were examined using 54 multiparous sows over a total of 72 lactations (35 days). The sows were randomly assigned to six treatments (1-6). Each group received the same basic diet, covering the requirements of energy and nutrients except Val (4.5 g native Val, i.e. 3.5 g apparent ileal digestible Val). Adding crystalline l-Val dietary Val concentrations of 5.5, 6.5, 8.5, 10.5 and 14.5 g/kg, respectively, were realized. Feed intake of the sows was determined daily, body weight was determined on day 110 of gestation and day 1, 22 and 35 of lactation. The piglets were weighed on day 1, 21 and 35. The intake of piglet feed, which was offered from day 21, was determined at day 35 for each litter. Milk yield was determined using the weigh-suckle-weigh-method at day 13, 14, 20 and 21, fat and protein contents were analysed in hand-milked samples with infrared spectroscopy. Feed intake (kg/day) of the sows during lactation averaged 2.9, 4.3, 4.6, 4.6, 4.9 and 5.1 for treatments 1-6, respectively. For treatments 1 and 2 body weight losses of the sows during lactation were higher (1207 and 805 g/day, respectively) and milk production was lower (7076 and 8686 g/day, respectively), compared with the average of treatments 3-6 (625 g/day body weight loss; 9263 g milk/day). Daily weight gain of the piglets was also lower (146 and 171 g/day vs. 200 g/day) leading to lower weaning weights of 6.6 and 7.5 vs. 8.5 kg. As a consistent growth depression of the piglets in Val deficiency must be assumed, at least 6.5 g Val corresponding to 5.5 g apparent ileal digestible Val per kg lactation feed must be recommended.     

Effect of enrofloxacin-Na against pathogens related to the respiratory and alimentary diseases in suckling and weanling piglets

A field trial was conducted to evaluate effect of enrofloxacin-Na against pathogens related to the respiratory and alimentary diseases in eighty suckling piglets (6-7 days old) and eighty weanling piglets (5-6 weeks old). Respective twenty of the suckling and weanling piglets were assigned to each of 4 experimental groups; control (non-treated), clinical injection dose (CID), 2x clinical injection dose (2CID). and premix. A 0.05 ml (2.5 mg) of enrofloxacin-Na injection (5% solution, 1 ml) per kg body weight of piglets as CID was injected intramuscularly for 3 days and the clinical signs were observed for 9 days. The premix (150 ppm) of enrofloxacin-Na was administered with feed for 7 days ad libitum and the clinical signs were observed for 13 days. The enrofloxacin-Na-treated piglets showed a higher increase in body weight and a lower feed per gain than the control piglets. In addition, the treatment of enrofloxacin-Na, regardless of the route of administration, decreased the incidence rate of diarrhea in suckling piglets and respiratory symptoms in weanling piglets. The isolation index of E. coli and Cl. perfringens during the treatment periods was also lowered by the enrofloxacin-Na treatment in both suckling and weanling piglets. The antibiotics was also evaluated as safe locally and whole bodily as treated by injection or feeding. These results indicate that the newly developed antibiotics, enrofloxacin-Na, is very useful for the prevention and therapy of swine diseases in the pig industry.     

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)     

Isoleucine and valine supplementation of a low-protein corn-wheat-soybean meal-based diet for piglets: growth performance and nitrogen balance

The effects of Ile and Val supplementation of a low-CP, corn-wheat-soybean meal-based piglet diet on growth performance, incidence of diarrhea, and N balance were studied using 60 Landrace x Duroc male piglets in a 4-wk experiment. The 60 individually caged piglets were divided into 5 dietary treatments, each consisting of 12 piglets. Diet 1 was a positive control diet (20% CP); diet 2 was a low-CP negative control diet (17% CP); diets 3, 4, and 5 were low-CP diets to which Ile, Val, or the combination of Ile and Val were added, respectively. All diets were supplemented with Lys, Met, Thr, and Trp to provide the required concentrations of these AA according to the 1998 NRC. Average daily gain and ADFI were similar among pigs fed the positive control, Val-added, and the Val plus Ile-added diets. On wk-2 and wk-4, fecal score was greater (softer feces) in piglets fed the 20% CP level compared with the remaining treatments (P < 0.01). Nitrogen intake was decreased (P < 0.0001) in pigs fed diets containing low levels of CP compared with pigs fed the 20% CP diet. Fecal N excretion (g/d) was decreased (P < 0.05) in piglets fed low-CP diets at wk 1 and wk 4 of feeding, and in urine at wk 4 of feeding. Crude protein levels or AA supplementation had no effect on N retention efficiencies. These results indicate that the supplementation of Val alone, or in combination with Ile, to a low-CP piglet diet with adequate levels of Lys, Met, Thr, and Trp is necessary to achieve maximum performance in pigs consuming corn-wheat-soybean meal-based diets.     

Effect of citric acid and calcium on the bioavailability of orally-administered oxytetracycline in piglets

The bioavailability of orally given oxytetracycline in dependence on calcium (0.7% and 1.4% calcium, respectively) and citric acid content in feed was examined in piglets (9.9 +/- 0.9 kg body weight). In the first trial no citric acid was added to the two feeds, in the second trial 1.5% citric acid was added. In both trials each piglet received an i/v-injection of oxytetracycline (dosage 10 mg/kg body weight) and an oral dose of oxytetracycline (40 mg/kg body weight). The blood samples, taken in definite time intervals, were analysed by a microbiological assay. With these results the kinetic parameters and the bioavailability were calculated. The results of the i/v-trials were identical. The kinetic parameters C1 = 14.91 micrograms/ml, lambda 1 = 3.46 h-1, Cz = 7.49 micrograms/ml and lambda z = 0.19 h-1 describe the graph after i/v-application. The calcium content of the feed had no significant influence on the kinetic parameters after p/o-application, but the piglets receiving citric acid showed a significant higher maximum concentration (Cmax). The bioavailability of orally given oxytetracycline was significantly (26%) increased by the citric acid content. In spite of the citric acid the bioavailability only came to 4.9%.     

The optimal vitamin B 6 requirement of early weaned piglets

In a two-period rearing trial (1st to 24th and 24th to 45th experimental day) using 72 early-weaned piglets, the optimal vitamin-B6 requirement was determined on the basis of different performance criteria and biochemical parameters. In the corresponding live weight ranges of 3.5 to 10 kg and 10 to 21 kg, the animals allotted in 6 groups were ad lib. fed a prestarter and starter feed, respectively containing 0.5, 1.2, 2.0, 2.8, 3.5 and 6.6 mg vitamin B6 per kg dry matter. For adequate feed intake and weight development, a dietary vitamin B6 content of 2.0 mg/kg and 1.2 mg/kg proved necessary for the 1st and 2nd part of the experiment, respectively. An optimal intermediary metabolic situation and thus an optimum vitamin B6 requirement covering, which was derived from the renal xanthurenic acid excretion and the SGOT activity, was attained only at a vitamin B6 supply level of 3.5 and 2.8 mg/kg for the 1st and 2nd experimental periods, respectively. This corresponds to an average vitamin B6 requirement per animal and day of 0.8 mg for the weight range 3.5 to 10 kg, and of 1.9 mg for the weight range 10 to 21 kg.     

发酵豆粕在断奶仔猪浓缩料中的应用研究

试验选择（35±2）日龄断奶仔猪120头,随机分为3个处理,每个处理5个重复,每个重复8头猪,进行为期21 d的饲养试验,研究两种发酵豆粕在断奶仔猪浓缩料中应用效果。结果表明,在断奶仔猪浓缩料中添加发酵豆粕能改善仔猪的生长性能,且不同的发酵豆粕应用效果不同。从试验全期来看,发酵豆粕试验组的日增重、日采食量、料重比均好于43豆粕对照组,但均差异不显著（P〉0.05）。试验Ⅱ组仔猪的生长性能表现最好。从试验结果来看,试验Ⅱ组效果最好,试验Ⅰ组次之,试验Ⅱ组仔猪日增重较试验Ⅰ组、对照组分别高8.26%、8.92%;试验Ⅱ组日采食量较试验Ⅰ组、对照组分别高4.32%、5.16%;试验Ⅱ组料重比较试验Ⅰ组、对照组低3.92%、4.32%。     

Endogenous N-losses in piglets estimated by a [15N]-isotope dilution technique: effect of xylanase addition to a wheat and rye based diet.

The nitrogen pool of piglets weighing 19.4 +/- 1.4 kg at the beginning of the experiment was labeled with an oral application of ([15N]H4)2SO4 (1.26 [15N]-atom percent excess of dietary N) over a period of 7 d. The labeling period was followed by an equilibration period of 7 d without feeding the labeling compound. The two experimental diets were based on wheat (53%) and rye (25%) and were fed either with or without a xylanase containing enzyme preparation over both experimental periods. Additionally, diets were supplemented with an indigestible marker during the 2nd period of the experiment to allow the calculation of endogenous N-losses in subsequent segments of the digestive tract of the pigs. These endogenous N-losses were estimated at the end of the experiment by analyzing feces, ingesta and urine for [15N]-enrichment assuming that [15N]-enrichment of urine represents the [15N]-enrichment of the precursor pool. Endogenous N-losses were not significantly affected by xylanase addition at any measurement site (stomach, 3 sections of the small intestine, total digestive tract). Endogenous N-proportions of total nitrogen amounted on average for the six pigs to 42 +/- 11% and 56 +/- 5% at the last section of the small intestine and over the whole digestive tract, respectively, which corresponded to endogenous N-losses of 2.8 +/- 1.3 g N/kg DM and 2.0 +/- 0.3 g N/kg DM, respectively.     

Excessive dietary selenium to primiparous sows and their offspring. I. Influence on reproduction and growth

The effect of high dietary selenium (Se) on the reproductive performance, growth and health in pigs was examined. Addition of 0 to 16 mg Se per kg feed to sows and their piglets up to nine weeks of age did not cause any manifest toxic effect. None of the sows died due to the Se treatment. The piglets were all fullborn and showed no macroscopic abnormalities. The treatment did not influence neither the number of liveborn and stillborn piglets in the litter, nor the survival of the piglets until 9 weeks of age. The weight of the whole litter at birth was unaffected by the Se supplementation, while there was a significant difference in body weight of the piglets at 9 weeks of age. The weaned pigs receiving 8 or 16 mg Se per kg feed had a reduced feed intake. As the feed utilization was unaffected by treatment, these pigs had a significantly lower weight at 9 weeks of age.     

肉鸡能量需要动态模型的建立和参数估计

本研究通过两个试验评价肉仔鸡的能量需要。试验1选用36只AA肉仔鸡新生雏笼养6周,分别于3周龄和6周龄评定2种饲粮的表观代谢能(AME)和表观氮校正代谢能(AMEn)。结果表明:氮校正使AME降低5%左右,AMEn和AME的相关性较强。试验2选用AA肉鸡新生雏240只,公母分饲笼养6周,每周测定空腹体重及采食量。用Compertz方程拟合公母鸡的生长曲线,微分建立日增重与日龄的函数关系,再与利用一元线性回归法建立的能量需要模型组合,形成动态的能量需要预测机制。     

Efficiency of Echinacea purpurea on performance and immune status in pigs

The aim of the present investigation was to examine the inclusion of the dried herb Echinacea purpurea (L.) MOENCH as feed additive in diets of sows, piglets, and grower/finisher pigs on growth performance, blood picture, plasma enzymes including proliferation of lymphocytes, antibody status, and protein and immune globulin content of colostrum. The control groups were supplemented with alfalfa meal. The sows (total 36) received 0%, 1.2%, or 3.6% Echinacea cobs in the diet from day 85 to day 110 of gestation and 0%, 0.5%, or 1.5% Echinacea cobs up to day 28 of lactation. No significant differences were found for growth performance, weight loss, blood picture, plasma enzymes, and colostrum composition. Performance of the sucking piglets was not impaired either during lactation or during a 4 week observation period after weaning. The health status was similar in all treatment groups. In a second experiment, lasting 6 weeks, with 36 piglets (5.8-22.1 kg body weight), 1.8% Echinacea cobs, or 20 mg/kg feed Flavomycin were supplemented. No significant differences were found for the recorded parameters. Feed conversion ratio (kg feed/kg gain) of the Echinacea group was slightly (4%) increased (1.54 vs. 1.60). In a third trial, 48 grower/finisher pigs were used during a 9-week experimental period with two supplementation phases (weeks 1-3 and weeks 7-9). The experimental groups received 0%, 1.5% cobs or 4-6 ml pressed juice (commercial standard) per day respectively. Vaccination with Swine erysipelas was implemented in weeks 1 and 5 to determine the specific immune response. Growth performance and blood picture for all groups were similar, however, feed conversion of both Echinacea supplemented groups was significantly (p < 0.03) better than of the unsupplemented control group (2.44 vs. 2.51). In addition, the Swine erysipelas antibodies showed a marked significance (p < 0.05) in regard of altitude in both supplemented groups. It is concluded, that E. purpurea might be used as a feed additive to achieve immune stimulating efficiency in pig production and increase feed-to-gain-conversion. The efficiency of cobs is comparable to a commercial juice product.     

Effects of essential oils from fennel (Foeniculi aetheroleum) and caraway (Carvi aetheroleum) in pigs

The ban of antibiotics as a feed additive requires alternatives to stabilize the health and performance particularly of the young animals. Essential oils obtained from fennel seed (Foeniculi aetheroleum) and caraway seed (Carvi aetheroleum) were tested in diets for weaned piglets in comparison with either a diet without feed additive or with a combination of formic acid and copper (positive control). Four groups of sixteen piglets (live weight 7 kg, age 26 days) received diets without (1) or with supplements of 7.5 g formic acid + 160 mg Cu/kg (2), 100 mg fennel oil/kg (3) or 100 mg caraway oil/kg (4) during 3 weeks after weaning. In the subsequent 4 weeks, all piglets were fed a diet without these additions. Fennel oil contained almost 2/3 anethol, approximately 1/5 fenchon and the remaining part consisting of alpha + beta-pinen, limonen (p-mentha-1,8-dien) and estragol. In the caraway oil, half of the contents was represented by limonen and the other half by carvon. There were no piglet losses and only few cases of diarrhoea. The combination of formic acid and copper increased feed consumption by 27% and daily weight gain by 25%. There were no differences in the performance between the group fed fennel oil and the control without additives. Piglets fed caraway oil tended to consume less feed and to gain approximately 10% less. In feed choice experiments, pigs consumed the same two diets from two troughs with 50% of total feed amount, as expected. The diets containing fennel or caraway oils were consumed at less than 50%. If the diet contained 100 mg fennel oil/kg, the decrease of percentual feed intake was significant. The results of the feeding experiment and of the feed choice experiment question the classification of fennel and caraway oils as flavour additives or as 'appetite promoters' in diets for weaned piglets.     

Effect of dietary L-carnitine supplementation on growth performance of piglets from control sows or sows treated with L-carnitine during pregnancy and lactation

Previous studies showed that supplementation of sows' diets with L-carnitine increases body weights of their piglets at birth. This study was performed to investigate whether piglets of sows treated with L-carnitine differ in their growth potential from that of piglets of untreated control sows after weaning. It was also investigated whether supplementation of piglets' diets with L-carnitine improves their growth after weaning. In two trials, piglets of the first litters of primiparous sows (trial 1) and the second litters of the same sows (trial 2) were divided into four groups: group 1, piglets of control sows, fed a control diet; group 2, piglets of control sows fed a diet supplemented with 30 mg L-carnitine/kg; group 3, piglets of L-carnitine-treated sows, fed a control diet; group 4, piglets of L-carnitine-treated sows fed a diet supplemented with 30 mg L-carnitine/kg. Mean initial body weights of the piglets of the four groups were identical. They were 8.5 kg in trial 1 and 12.5 kg in trial 2. Diets were fed ad libitum over a period of 35 days. Piglets from sows treated with L-carnitine did not differ in body weight gains, feed intake and gain : feed ratio from those of control sows. In trial 1, piglets supplemented with L-carnitine had higher body weight gains (p < 0.005) and showed a tendency towards a higher gain : feed ratio (p = 0.09) than piglets fed the control diets. In trial 2, no significant difference in these parameters emerged between piglets fed the diet supplemented with L-carnitine and those fed the control diet. In conclusion, this study shows that dietary L-carnitine treatment of sows does not improve the growth potential of their piglets after weaning under the conditions of equal initial body weights. The study also shows that L-carnitine supplementation of their diets improves the growth performance in light piglets of primiparous sows.     

日粮粗蛋白质水平对哺乳母猪及仔猪生产性能的影响

选用分娩日期相近的天津白猪 1 8头 ,按胎次、体重随机分成 3个处理组 ,每个处理 6个重复 ,每个重复 1头母猪。哺乳母猪自由采食 ,自由饮水。 3个处理日粮的蛋白质水平分别为 1 4.0 %、1 6.5%、1 9.0 %。试验期为 7周。分别于母猪分娩后 0天、3 5天测定背膘厚度、体重、采食量 ;对仔猪隔周称重 ;母猪分娩后 2 1天于前腔静脉采血 ,分离血清后分析血清尿素氮、血清总蛋白、肌酸酐。 2 8天在第一、最后两对有效乳头取奶样 ,分析总固形物、乳蛋白、灰分。试验结果表明 ,母猪体重损失、背膘厚度、采食量、乳成分、以及哺乳期仔猪增重在 3个蛋白水平上差异不显著。高蛋白日粮有提高母猪产奶量的趋势(P <0 .0 7)。母猪的血清尿素氮浓度处理间差异极显著 (P <0 .0 1 )。     

免疫应激对肉仔鸡苏氨酸、赖氨酸需求比例的影响

选用300只16日龄的AA肉公鸡,研究了免疫应激对内源氨基酸损失和日粮氨基酸消化率的影响.选用750只1日龄AA肉公鸡,采用2×5因子设计,研究了免疫应激和日粮苏氨酸/赖氨酸比例对1～21日龄期间生长性能、内分泌激素水平和血清尿酸浓度的影响.结果表明,免疫应激直接增加肉仔鸡内源氨基酸损失,同时又通过降低干物质采食量显著减少内源损失,但没有影响日粮氨基酸消化率.免疫应激也降低了肉仔鸡生长性能,日粮苏氨酸/赖氨酸比例对肉仔鸡增重的影响与免疫状态有关.对照组获得最大增重和最低耗料/增重比需要的日粮苏氨酸/赖氨酸比例均为64/100,应激组相应的需求比例分别为70/100和71/100.     

Effects of different management factors on broiler performance and incidence of tibial dyschondroplasia

(1) This study was to determine the effects of two lighting programmes (continuous--24L:0D or intermittent--12L:3(1L:3D)), two feeding programmes (continuous--ad libitum or meal Jeeding--3 h feed:3 h deprivation x 4 times per d) and two ascorbic acid (AA) supplementations (0 or 150 mg/l in water) on broiler performance and incidence of tibial dyschondroplasia (TD). (2) One-day-old male commercial (Ross PM3) broiler chicks (1600) were used. The chicks were randomly divided into 8 treatment groups (2 x 2 x 2) and their replicates (2) replicates per treatment). (3) Intermittent lighting increased body weight and improved feed conversion. Body weight of broilers was decreased by meal feeding. AA supplementation had no significant effect on the body weight and feed conversion ratio. There was no lighting x feeding x supplemental AA interaction for body weight, feed conversion ratio, mortality rate and carcase weight. (4) Supplemental AA improved the cortical thickness of tibiotarsus and decreased the incidence of TD. (5) It was concluded that the application of intermittent lighting in combination with supplementation of 150 mg/l AA is a useful method to reduce TD in broilers without loss of performance.     

Dietary probiotic supplementation and resulting effects on performance, health status, and microbial characteristics of primiparous sows

In an experiment with 33 first-litter sows from day 90 of pregnancy to day 28 of lactation, the influence of a probiotic supplementation on weight performance, feed intake, litter sizes, litter weights, health status and microbiological profile was tested. Enterococcus faecium DSM 7134 was supplemented in a concentration of 5 x 10(8) CFU/kg feed to the gestation and lactation diets of gilts. The supplemented sows showed a significant higher improvement of feed intake (4.16 vs. 3.71 kg/day), litter size (9.2 vs. 7.7 piglets) and weight performance. The average live weight of the probiotic sows at day 28 of lactation was 11 kg higher than of the controls. The bacterial counts/g faeces (lactobacilli, Gram-positive anaerobes, Gram-negative anaerobes, Escherichia coli and enterococci) and the incidence of adhesive and haemolytic E. coli organisms revealed no significant differences between the sows of the two groups or their piglets. While the litter size cannot necessarily be assumed as a primary effect of the probiotic supplementation, the significantly better feed intake and weight performance might be partly due to the probiotic use and can prevent "starvation sterility" of young sows after their first litter caused by reduced feed intake during lactation with high mobilization of body tissue accompanied with lack of energy.     

苦玄参提取物对仔猪生长性能的影响研究

[目的]试验旨在探讨苦玄参提取物对仔猪生长性能的影响,为其在动物生产中更好地应用提供参考依据。[方法]选取体重相近的28~35日龄杜×长×大三元杂交的健康断奶仔猪250头,随机分为5组(A、B、C、D、E组),每组设5个重复,每个重复10头。其中,A、B、C组依次为苦玄参提取物高、中、低3个剂量试验组,分别在基础日粮中添加3.500、1.750和0.875g/kg苦玄参提取物;D组在基础日粮中添加对照药物七补散4.0g/kg;E组为空白对照组,饲喂基础日粮,预饲期7d,正试期30d。于试验正式开始的第0天、第15天和第30天7:00分别对各组的每一头试验猪进行空腹称重,并每天记录每个组试验猪的采食量,计算平均日采食量(ADFI)、平均日增重(ADG)和料重比(F/G)。[结果]添加苦玄参提取物后,A、B、C组仔猪的体重、ADG及ADFI,与E组相比显著或极显著(P<0.05或P<0.01)增加,而料重比降低;其中苦玄参提取物中剂量组仔猪的体重、平均日增重及平均日采食量提升最明显,料重比也极显著低于D组与E组(P<0.01)。[结论]苦玄参提取物对仔猪生长具有一定的促进作用,以1.750g/kg的添加剂量添加在饲料中效果最佳。