Evaluation of site and age of weaning on pig growth performance

Site-segregated early weaning (SSEW) refers to the practice of weaning pigs from the sow at an early age and placing them in a nursery that is physically isolated from the breeding herd. An experiment involving 369 pigs was conducted at the Prairie Swine Center to investigate the impact of SSEW on pig performance when the herd of origin has a high health status and when housing and management conditions are kept as similar as possible across weaning regime. Three treatments were compared: weaning at 21+/-3 d and keeping the pigs on-site in an all-in-all-out nursery room (Control), weaning at 12+/-2 d of age and keeping the pigs on-site in a separate but identical all-in-all-out nursery room (OSEW), or weaning at 12+/-2 d of age and moving the pigs off-site to an all-in-all-out nursery room located 16 km from the Center (SSEW). Ventilation, feed, penning, feeders, and drinkers were kept as similar as possible for all treatments. Off-site weaning improved 56-d body weight (P < .05) by 12.5 and 8.3% compared with OSEW and Control, respectively. The improvement appeared to be the result of improvements primarily in feed intake but also due to enhanced efficiency of nutrient utilization. This experiment confirms that SSEW results in significant improvements in 56-d weights, even when the herd of origin has a relatively high health status.     

Relationship between weaning age and antibiotic usage on pig growth performance and mortality

A total of 2,184 pigs (DNA 600 × PIC L42) were used to evaluate the effects of weaning age and antibiotic (AB) use on pig performance from weaning to marketing in a commercial production system. Experimental treatments were arranged in a 3 × 2 factorial with main effects of weaning age (18.5, 21.5, or 24.5 d of age) and with the use of ABs or an antibiotic-free (NAE) program. At birth, pigs were ear tagged, and the date of birth and sex recorded. Pigs were weaned from a 4,000-sow farm over four consecutive weeks. Four weaning batches (one per week) of 546 pigs were used. Each weaning batch had one-third of pigs of each weaning age. Pigs were placed in pens by weaning age and then randomly assigned to an AB or NAE program. There were 14 replicate pens per treatment and 26 pigs per pen (13 barrows and 13 gilts). Pigs allocated to the AB program were fed a diet containing 441 mg/kg chlortetracycline (CTC) from day 8 to 21 postweaning. They were also administered 22 mg/kg of body weight (BW) of CTC via drinking water for five consecutive days after a porcine respiratory and reproductive syndrome outbreak during week 7 after weaning. In the first 42 d postweaning, increasing weaning age improved (linear, P < 0.001) BW at day 42, average daily gain (ADG), and average daily feed intake (ADFI). From weaning to 197 d of age, increasing weaning age increased (linear, P < 0.001) ADG and ADFI. Pigs on the AB program had greater (P = 0.031) ADG and ADFI compared with NAE pigs. An interaction (linear, P = 0.005) was observed for feed efficiency (G:F). When ABs were provided, increasing weaning age did not result in any change in G:F; however, in the NAE program, increasing weaning age increased G:F. Pigs on the AB program had lower (P < 0.001) total losses (mortality and removals) than those on the NAE program. Increasing weaning age marginally (linear, P = 0.097) decreased total losses. Increasing weaning age decreased (quadratic, P < 0.001) the number of pigs treated with an injectable AB but the AB program did not (P = 0.238). The weight sold (at 197 d of age) per pig weaned was increased (linear, P = 0.050) by increasing weaning age and by using AB in feed and water (P = 0.019). In summary, increasing weaning age linearly improved most of the pig performance criteria and relatively the short-term use of ABs reduced mortality and removals with both factors contributing to increased weight sold per pig weaned.     

Effect of group size on pig performance in a wean-to-finish production system

Crossbred pigs (n = 1,400) were used to evaluate the effect of group size (25 vs 50 vs 100 pigs/pen) in a wean-to-finish production system on growth performance and carcass measures. Pigs were weaned at 17 d (range = 15 to 19) of age with a mean initial BW of 5.9 +/- 0.02 kg and taken to a final mean pen weight of 116 +/- 0.9 kg. A 10-phase dietary regimen was used, and pigs had free access to feed and water. Feeder-trough space (4.3 cm/pig) and floor-area allowance (0.68 m2/pig) were the same for all group sizes. Compared to groups of 25, pigs in groups of 50 and 100 animals were lighter (P < 0.001) at the end of wk 8 after weaning and had lower (3%, P < 0.01) ADG and gain:feed (G/F) but similar (P > 0.05) ADFI during the first 8 wk of the study. At the end of the study, pig weight and the coefficient of variation in pig weight within a pen were similar (P > 0.05) across group sizes. During the period from 8 wk after weaning to the end of the study, pigs in groups of 100 compared to 50 animals had greater (3%, P < 0.01) ADG, and pigs in groups of 25 were intermediate for ADG. Average daily feed intake during this period was similar (P > 0.05) for all group sizes; however, G/F was greater (3%, P < 0.01) for groups of 100 compared to 25 or 50 animals. For the overall study period, ADG, ADFI, and G/F from weaning to slaughter weight were similar across group sizes (P > 0.05; 655, 648, and 658 g; 1,759, 1,755, and 1,759 g; and 0.37, 0.37, and 0.37; for ADG, ADFI, and G/F, respectively, for groups of 25, 50, and 100 pigs, respectively). Mortality was similar (P > 0.05) across group sizes; however, morbidity (pigs removed due to poor health or injury) was higher in groups of 25 pigs compared to the other two group sizes (7.0, 3.5, and 3.9% for groups of 25, 50, and 100, respectively; P < 0.05). Group-size treatment did not affect (P > 0.05) carcass dressing percentage, backfat thickness, or loin-eye depth. In summary, growth performance from weaning to market weight was not affected by group size.     

断奶后日粮中超剂量地添加植酸酶可提高仔猪的生产性能

提高断奶仔猪的生产性能一直是养猪生产系统关注的重点,因为仔猪有一个最佳的生长开端很重要.最大化地促进仔猪21 d断奶时达到最大的生产性能被认为是与其终生生产性能以及生产者最终盈利密切相关.这常常导致给断奶仔猪使用专门的开食料,这种饲料通常比之后使用的保育期饲料更为复杂,含有高比例的动物蛋白和乳清产品.传统上,这些专用的断奶日粮在断奶早期一般添加较低水平的植物源性蛋白.     

犊牛生产体系和断奶后的管理对其生长性能的影响

文章旨在评估犊牛生产系统和断奶后管理对其生长性能和胴体特征的影响。试验采用2×2因子设计,两个生产系统(在玉米秸秆上饲养和在干燥环境饲养),两个断奶后的管理(直接育肥和采用生长-育肥两阶段饲养)。结果显示:与冬季在干燥环境饲养的牛相比,冬季在玉米秸秆上过冬的犊牛初始体重较轻(P <0.05)。同时,冬季在干燥环境下饲养的犊牛较在玉米秸秆上过冬的犊牛日增重显著提高(P <0.05)。前期在玉米秸秆上过冬的犊牛在生长-育肥期的初始体重显著低于在干燥环境饲养犊牛(P <0.05)。但在玉米秸秆上过冬的犊牛较干燥环境饲养的犊牛存在代偿性反应特征,表现为日增重和饲料报酬显著提高(P <0.05)。在评价断奶后管理对生长性能的影响时,生长-育肥期犊牛较育肥期犊牛初始体重、末重和干物质摄入量显著提高(P <0.05)。但与生长-育肥期犊牛相比,育肥期犊牛日增重和饲料报酬显著提高(P <0.05)。断奶后的管理和生产体系对大理石纹的影响具有显著交互效应(P <0.05)。在玉米秸秆上过冬的生长-育肥组较其他组显著提高了大理石纹评分(P <0.05)。结论:与断奶后直接饲喂育肥期饲料的犊牛相比,采用生长-育肥两阶段饲喂方式的犊牛胴体重量显著提高。然而,直接饲喂育肥料的犊牛饲料报酬和日增重均提高,两阶段饲喂方式的犊牛在经济收益上无显著差异。     

Prevalence and antimicrobial resistance of MRSA across different pig age groups in an intensive pig production system in Australia

This observational study aimed to determine MRSA prevalence using strain‐specific real‐time PCR at the pig level, stratified by age groupings, within a pig enterprise. A total of 658 samples were collected from individual pigs (n = 618) and the piggery environment (n = 40), distributed amongst five different pig age groups. Presumptive MRSA isolates were confirmed by the presence of mecA, and MALDI‐TOF was performed for species verification. All isolates were tested against 18 different antimicrobials. MRSA was isolated from 75.2% (95% CI 71.8–78.6) of samples collected from pigs, and 71% of the MRSA isolates from this source were identified as community‐associated (CA)‐MRSA ST93, while the remainder were livestock‐associated (LA)‐MRSA ST398. Amongst environmental isolates, 80% (CI 64.3–95.7) were ST93 and the remainder ST398. All MRSA isolates from pigs and the environment were susceptible to ciprofloxacin, gentamicin, linezolid, mupirocin, rifampicin, sulfamethoxazole–trimethoprim, teicoplanin and vancomycin. Phenotypic rates of resistance were penicillin (100%), clindamycin (97.6%), erythromycin (96.3%), ceftiofur (93.7%), chloramphenicol (81.2%), tetracycline (63.1%) and amoxicillin–clavulanate (63.9%). A low prevalence of resistance (9.2%) was observed against neomycin and quinupristin–dalfopristin. The probability of MRSA carriage in dry sows (42.2%) was found to be significantly lower (p < .001) when compared to other age groups: farrowing sows (76.8%, RR1.82), weaners (97.8%, RR 2.32), growers (94.2%, RR 2.23) and finishers (98.3%, RR 2.33). Amongst different production age groups, a significant difference was also found in antimicrobial resistance for amoxicillin–clavulanate, neomycin, chloramphenicol and tetracycline. Using the RT‐PCR assay adopted in this study, filtering of highly prevalent ST93 and non‐ST93 isolates was performed at high throughput and low cost. In conclusion, this study found that weaner pigs presented a higher risk for CA‐MRSA and antimicrobial resistance compared to other age groups. These findings have major implications for how investigations of MRSA outbreaks should be approached under the One‐Health context.     

Integrated resource-driven pig production systems in a mountainous area of Northeast India: production practices and pig performance

Data on pig production system was derived through structured household interviews from a total number of 320 rural households and performance of pigs was assessed. Results revealed that the pig production system represented mixed farming based mainly on the common property resources. Majority of the pigs were reared in intensive system and fed with home made cooked feed (kitchen waste and locally available plants). The body weight of crossbred, Burmese and local pigs were 67, 65.4 and 45.6 kg, respectively at 12 months of age with average daily body weight of 184, 179 and 125 g, respectively. The overall mortality among the pigs was 17.96%. The major causes of mortality in pigs were Swine fever, Swine erysipelas, digestive disorders, nephritis and respiratory disorders. The body weight gain in pigs subjected to deworming and mineral mixture supplementation (218 g/day) was significantly (p < 0.05) higher than the control group (178 g/day). The input output ratio was 1:1.7 for both crossbred and Burmese pigs, while the corresponding ratio for local pigs was 1:1.2. It is inferred that the smallholder resource driven pig production system is economically viable and sustainable at household level and there is enough scope to improve the smallholder resource driven pig production system.     

Calving system and weaning age effects on cow and preweaning calf performance in the Northern Great Plains

A 3-yr study evaluated late winter (Feb), early spring (Apr), and late spring (Jun) calving systems in conjunction with varied weaning strategies on beef cow and calf performance from Northern Great Plains rangelands. Crossbred cows were randomly assigned to one of three calving systems (on average n= 168.calving system(-1).yr(-1)) and one of two weaning times (Wean 1, 2) within each calving system. The Feb and Apr calves were weaned at 190 and 240 d of age, whereas Jun calves were weaned at 140 and 190 d of age. Breeding by natural service occurred in a 32-d period that included estrous synchronization. Cows were managed throughout the year as appropriate for their calving season. Quantity and quality of hay and supplements were provided based on forage and weather conditions, physiological state of the cows, and available harvested feed resources within a year. After weaning, two-thirds of the early weaned steers were fed in confinement in Montana, and one-third were shipped to Oklahoma and were grazed or fed forage. One-half of the early weaned heifers grazed seeded pastures, and the other half was fed in confinement. Early weaned calves were weighed on approximately the same day as late-weaned calves. Birth weight and overall rate of gain from birth to weaning did not differ for calves from the three calving systems. Calf weaning weight differed by weaning age within calving system (P = 0.001), and calves from the Jun calving system that were weaned at 190 d of age tended (P = 0.06) to be lighter than calves of the same age from the Feb or Apr calving systems. Cow BW change and BCS dynamics were affected by calving system, but the proportion of cows pregnant in the fall was not. Cows suckled until later dates gained less or lost more BW during the 50 d between the first and second weaning than dry cows during this period. The previous year's weaning assignment did not affect production in the following year. Estimated harvested feed inputs were less for the Jun cows than for the Feb and Apr cows. We conclude that season of calving and weaning age affect outputs from rangeland-based beef cattle operations.     

母猪批次化生产提高猪场综合效益

批次化管理应用最早源自工业批次化管理,应用在畜牧业逐渐转化成母猪等畜禽批次化生产管理.母猪生产批次化管理是利用生物技术,根据母猪群大小进行批次生产,达到同期发情、同时排卵、同时配种和同时分娩的目的,是一种提高猪场母猪群繁殖性能的高效管理体系.近两年来非洲猪瘟给中国生猪养殖行业造成巨大损失.由于母猪批次化生产对猪场生物安...     

谷氨酰胺对断奶仔猪生产性能和血液生化指标的影响

试验选取21日龄的杜×长×大三元断奶仔猪66头,随机分为2组,每组3个重复,每个重复9～13只,研究日粮中添加1%的谷氨酰胺对断奶仔猪生长性能和血液生化指标的影响.结果表明,添加1 %的谷氨酰胺可使断奶仔猪21～35日龄阶段平均日增重比对照组提高19.2 %(P<0.05),平均日采食量提高16.3 %(P<0.05),血清碱性磷酸酶含量提高74.3 %(P<0.05),血清尿素氮含量降低35.4 %(P<0.05),腹泻率明显降低.添加1 %的谷氨酰胺还可使断奶仔猪21～49日龄阶段平均日增重提高11.5 %(P<0.05),35～49日龄阶段血清尿素氮含量降低43.7 %(P<0.05).     

The effects of dietary energy concentration and weaning site on weanling pig performance

This study was conducted to evaluate the effects of dietary energy density and weaning environment on pig performance. Treatment diets were formulated to vary in DE concentration by changing the relative proportions of low (barley) and high (wheat, oat groats, and canola oil) energy ingredients. In Exp. 1, 84 pigs in each of 3 replications, providing a total of 252 pigs, were weaned at 17 x 2 d of age and randomly assigned to either an on-site or an off-site nursery and to 1 of 3 dietary DE concentrations (3.35, 3.50, or 3.65 Mcal/kg). Each site consisted of a nursery containing 6 pens; 3 pens housed 7 barrows and 3 housed 7 gilts. All pigs received nontreatment diets in phase I (17 to 19 d of age) and phase II (20 to 25 d of age), respectively. Dietary treatments were fed from 25 to 56 d of age. Off-site pigs were heavier at 56 d of age (23.4 vs. 21.3 kg; P < 0.05) and had greater ADFI (0.77 vs. 0.69 kg/d; P < 0.01) than on-site pigs. There was a linear decrease in ADG (P < 0.01) and ADFI (P < 0.001) with increasing DE concentration. Efficiency of gain improved (P < 0.01) with increasing DE concentration. There was no interaction between weaning site and diet DE concentration, indicating that on-site and off-site pigs responded similarly to changes in diet DE concentration. In Exp. 2, nutrient digestibility of the treatment diets used in Exp. 1 was determined using 36 pigs with either ad libitum or feed intake restricted to 5.5% of BW. Energy and N digestibility increased (P < 0.001) with increasing DE concentration. Nitrogen retention and daily DE intake increased with DE concentration in pigs fed the restricted amount of feed (P < 0.05). These results indicate that weaning off-site improves pig weight gain. The weanling pig was able to compensate for reduced dietary DE concentration through increased feed intake. Growth limitation in the weanling pig may not be overcome simply by increasing dietary DE concentration.     

Dietary rice improves growth performance,mucosal enzyme activities and plasma urea nitrogen in weaning piglets

In this study, we evaluated the nutritional functions of rice for weaning piglets. Sixteen weaning piglets with an average initial weight of 7.2 kg were divided into two groups. One group was fed a corn‐soybean meal based diet, and the other was fed a rice‐soybean meal based diet, containing 50% corn and rice, respectively. A 2 weeks growth trial was conducted and growth performance, intestinal mucosal enzyme activities and plasma urea nitrogen were measured. The average daily gain in rice‐fed piglets was significantly higher than that in corn‐fed piglets and the average daily feed intake tended to be higher in rice‐fed piglets than in corn‐fed piglets. Maltase and aminopeptidase activities (mol/g tissue) in the jejunum in rice‐fed piglets were significantly higher than those in corn‐fed piglets, although these enzyme activities were not different in the duodenum. Sucrase and dipeptidyl peptidase IV activities in the two groups were not different in either the duodenum or jejunum. Although the feed (nitrogen) intake was higher in rice‐fed piglets, the plasma urea nitrogen in rice‐fed piglets was significantly lower (P = 0.006) than that in corn‐fed piglets. These results indicate that rice is a good alternative feedstuff for the diet of weaning piglets.     

音乐刺激对断奶仔猪行为和生长的影响

本试验采用随机分组设计，选用４５日龄断奶的长白仔猪３２头。随机分成对照组和试验组，试验组每天接受３小时的音乐刺激，进行对比试验。经２５天试验表明，试验组在４天后就能适应音乐刺激，平均卧息时间较对照提高７．７４％，活动时间下降５．２６％，断奶应激行为明显省于对照组；同时，平均日增重提高１０．０７％（Ｐ〉０．０５），饲料利用率提高５．７６％。     

音乐刺激对断奶仔猪行为和生长的影响

本试验采用随机分组设计,选用45日龄断奶的长白仔猪32头,随机分成对照组和试验组,试验组每天接受3小时的音乐刺激,进行对比试验.经25天试验表明,试验组在4天后就能适应音乐刺激,平均卧息时间较对照组提高7.74%,活动时间下降5.26%,断奶应激行为也明显少于对照组;同时,平均日增重提高10.07%(P>0.05),饲料利用率提高5.76%.     

Intermittent suckling with or without comingling of non-littermate piglets before weaning improves piglet performance in the immediate post-weaning period when compared with conventional weaning

Background: In this experiment, intermittent suckling(IS) with or without the co-mingling(Co M) of piglets was studied as a method to stimulate solid feed intake and reduce post-weaning stress.Methods: Three weaning regimes using 30 multiparous sows were compared:(1) conventional weaning(CW)(n = 10 litters), where piglets had continuous access to the sow until weaning(d 0, farrowing = d-25 relative to weaning);(2) intermittent suckling(IS)(n = 10 litters), where piglets were separated from the sow for 8 h/d starting at d-7(relative to weaning); and(3) intermittent suckling with co-mingling(ISCo)(n = 10 litters) where IS started at d-7 and two litters were housed together during separation and then returned to their original sow. Ad libitum creep feed was available from d-17. At weaning pigs were housed in pens of 11 pigs, 27 pens in total. The ISCo treatment was divided in half to examine effects of different mixing strategies after weaning. Half of the ISCo litters were kept in familiar groups(ISCo F, familiar, n = 4) and the other half were mixed within treatment resulting in groups of unfamiliar pigs(ISCo NF, not familiar, n = 5), the same as IS(n = 9) and CW(n = 9) treatments.Results: The ISCo piglets ate more creep feed in the week before weaning(P 0.01), but also showed more aggressive and manipulative behaviour on first day of Co M compared with CW piglets(P 0.05). IS with or without Co M increased exploratory and play behaviour on the first day of treatment intervention(P 0.001) and increased sleeping behaviour on the last day of treatment intervention compared with CW(P 0.001). Mixing strategy at weaning had an effect on performance data with the highest growth and feed intake seen in ISCo F pigs 2 to 8 d after weaning(P 0.001). IS and ISCo NF pigs also grew faster and ate more than CW pigs 2 to 8 d after weaning(P 0.001). Post-weaning injury scores suggested reduced aggression in ISCo as evidenced by reduced redness(skin irritation)(P 0.05), and a tendency for ISCo to have less scratches than CW(P 0.1). The IS pigs slept the most and displayed less manipulative behaviours on the day of weaning and plasma haptoglobin levels remained low in IS pigs after weaning(P ≤ 0.01).Conclusions: Both intermittent suckling techniques improved production indices in the immediate post-weaning period. However, the addition of co-mingling before weaning in combination with grouping familiar pigs together after weaning improved performance in an additive manner.     

Effects of weaning weight, co-mingling, group size and room temperature on pig performance

Four experiments involving 3- to 4-wk-old, ad libitum-fed weanling pigs (n = 809) were conducted to determine the effects of initial pig weight, co-mingling of litters, numbers of pigs/pen and room temperature on pig performance in a conventionally equipped nursery. Pigs that were largest at birth were largest (P less than .01) at weaning (r = .66) and also at 28 d postweaning (r = .62). Light-weight pigs (3.8 kg) at weaning gained more slowly (P less than .05) for 4 wk postweaning than heavy weight pigs (6.5 kg). Growth curves for the light and heavy groups of pigs remained parallel throughout the 4-wk nursery period, indicating that small pigs were not making compensatory gains. Growth rates of average-weight pigs (5.2 kg) were intermediate to and not different (P greater than .05) from light- and heavy-weight pigs. Penning 8, 16 or 24 pigs together while maintaining constant flooring area and feeder and waterer space/pig did not reduce (P greater than .05) intakes, gains or feed:gain ratios. Co-mingled litters grew comparably (P greater than .05) to pigs reared as littermates. In temperature studies, pigs were reared either in a room maintained at 29 +/- 2.8 C throughout the 28-d trials or at 29 +/- 2.8 C the first week postweaning and 24 +/- 2.8 C thereafter. Reducing the nursery temperature to 24 +/- 2.8 C after 1 wk depressed (P less than .05) intakes, gains and feed efficiencies as compared with the warmer temperature regimen.     

Influence of two supplemental vitamin E levels and weaning age on performance, humoral antibody production and serum cortisol levels of pigs

Three trials using 156 Yorkshire x Hampshire x Duroc crossbred pigs (avg initial wt, 7.9 kg) were conducted to evaluate the effects of two supplemental dietary vitamin E (11 vs 220 IU/kg of diet) and weaning age (21, 28 or 35 d) on performance and immunocompetence of pigs. Supplemental vitamin E (220 IU/kg of diet) increased (P less than .01) serum concentrations of vitamin E for all weaning ages compared with pigs fed 11 IU of vitamin E/kg of diet. However, supplemental vitamin E did not affect performance, serum cortisol concentration or the primary and secondary antibody response to sheep red blood cells. As weaning age increased, weekly ADG and avg daily feed intake increased linearly (P less than .01). Cortisol levels decreased during the 1st wk following weaning and then increased linearly (P less than .01) over time; pigs weaned at 35 d of age had higher (P less than .01) cortisol values initially and over time than pigs weaned at 21 and 28 d. Pigs weaned at 35 d had a higher (P less than .01) primary response to sheep red blood cells than pigs weaned at 21 and 28 d of age, but this effect was not observed for the secondary response. There were no interactive effects (P greater than .10) of dietary vitamin E level and weaning age. In summary, the highest level of supplemental vitamin E increased serum vitamin E concentration but did not affect performance, cortisol levels or one test of the immune response, antibody titers to red blood cells.(ABSTRACT TRUNCATED AT 250 WORDS)     

酪蛋白酶解物对断奶仔猪免疫功能及生长性能的影响

试验选取21日龄杜×大×长断奶仔猪30头,分为对照组和试验组,对照组饲喂基础日粮,试验组仔猪每头每天在基础日粮的基础上添加2g酪蛋白酶解物,研究酪蛋白酶解物对断奶仔猪免疫功能和生长性能的影响。试验结果表明,试验组仔猪血清中IgA、IgG和IgM的水平分别比对照组提高15.85%(P<0.01)、2.04%(P>0.05)、7.89%(P<0.05);试验组与对照组仔猪相比,血清补体C3、C4水平差异不显著;对照组和试验组仔猪外周血淋巴细胞增殖率分别为14.19%、22.52%,差异极显著(P<0.01);试验组仔猪的日增重较对照组有明显的提高。     

断奶日龄和断奶后饲喂策略对10周龄仔猪生产性能的影响

1 研究背景断奶这一过程,对于仔猪来说是一个非常大的应激.仔猪断奶后,面临着生理的、环境的、心理和营养性的应激,进而对仔猪肠道结构造成损伤,目前欧盟已经禁止仔猪在21日龄前断奶.断奶后一段时间,常常伴随着低采食量,较差的生产速度,甚至严重的腹泻情况.断奶后前几天低的采食量完全不能满足仔猪营养的需求,一般需到断奶后的2～3周,仔猪采食量才能满足其营养需要,达到断奶前的生长速度.仔猪断奶后的生长速度已被证实具有巨大的提升空间,如何缩短断奶后的生长缺陷已经成为当今仔猪营养领域一个非常重要的研究课题.