Static spatial requirements of growing-finishing and heavy pigs

The objective of this study was to estimate the space occupied by a pig, calculated from direct measurements on the animal or from digital images. A total of 100 pigs with body weight (BW) ranging from 47 to 198 kg were individually weighed and measured for body length, back and shoulder height. The area of the rectangle into which each pig can be fitted was calculated, following the same method as Petherick and Baxter [Petherick, J.C., Baxter, S.H., 1981. Modelling the static spatial requirements of livestock. In: MacCormack, J.A.D. (Ed.), Proceedings of the CIGR Section II Seminar on Modelling, Design and Evaluation of Agricultural Buildings, Aberdeen, August 1981, Scottish Farm Buildings Investigation Unit, Bucksburn, Aberdeen, UK. pp 75–82]. In addition, pictures of the pigs were taken with a digital camera at the same distance and resolution to estimate the area of the geometrical shape of each animal by counting the number of pixels. Values of Petherick and Baxter's data space (A = 0.047 × BW^0.67) are significantly higher (p < 0.0001) than those found with our linear measurements (A = 0.041 × BW^0.67). The areas calculated from linear measurements support the EU Council Directive 2001/88/EC for pigs in the weight class of 115–150 kg, but not for growing pigs. This is because the area recommended for pigs of 110 kg corresponds only to our minimum space allowance, as estimated from digital image analysis (A = 0.028 × BW^0.67).     

Dietary sodium and chloride levels for growing-finishing pigs

The performance and the physiological and metabolic consequences of three dietary levels of Na (.03, .09 and .18%) and of Cl (.08, .17 and .32%) arranged factorially were determined in growing-finishing pigs (36 to 89 kg). Average daily gain and feed efficiency of pigs fed .03% Na were lower than pigs fed .09 or .18% Na. Gain:feed ratio of pigs fed .32 or .17% Cl was greater than that of pigs fed .08% Cl during the finishing phase (58 to 89 kg) but not during the growing phase. Increasing dietary Cl levels increased average daily feed intake and gain:feed ratio of pigs fed .03% Na, but had no effect at the higher levels of Na. Plasma Na and Cl were lower (P less than .05) while plasma K (P less than .01), total protein, (P less than .04), albumin (P less than .07) and urea N (P less than .03) were higher in pigs fed .03% Na compared with those fed .09 or .18% Na. Increasing the dietary levels of Cl decreased urea N (P less than .05). Plasma lysine:arginine ratio increased as dietary Cl increased in pigs fed .18% Na diets, but not in pigs fed .03 or .09% Na. The urea cycle intermediate ornithine was highest in the plasma of pigs fed .18% Na. Dietary Na and Cl seem to interact to affect both plasma electrolytes and basic amino acid metabolism.     

微颗粒饲料的研究与应用

微颗粒配合饲料又名人工浮游生物，美国科学家自 20世纪 60年代率先进行这方面的研制和生产，一些水产研究发达国家如日本、美国、英国等已开始生产和销售微颗粒饲料。随着研究的深入，微颗粒配合饲料在营养和性状上越来越完善，其适口性、水中悬浮性和稳定性越来越好，特别是针对鱼、虾、蟹及贝类幼体的生长特性、营养需求，配制生产专用的微颗粒饲料，经过与轮虫、卤虫并用到完全替代轮虫和卤虫，微颗粒配合饲料的研究和应用取得了突破性进展。目前，微颗粒配合饲料可以单独使用，也可与浮游生物混合使用进行育苗生产，因此具有广阔的应用…     

饲料桑粉对生长育肥猪的营养价值评定

选取健康、胎次一致的杜长大三元杂交去势公猪6头,采用全收粪法进行消化试验,测定生长育肥猪对饲料桑粉的各常规营养成分的表观消化率和消化能,确定饲料桑粉对生长育肥猪的营养价值。结果表明,饲料桑粉的总能、总能表观消化率和表观消化能分别为15.70MJ/kg、68.04%和10.66MJ/kg;粗蛋白质含量、表观消化率和可消化粗蛋白质分别为20.04%,76.49%,15.33%;粗脂肪含量、表观消化率和可消化粗脂肪分别为3.55%,29.77%,1.06%;粗纤维含量、表观消化率和可消化粗纤维分别为17.18%,31.52%,5.41%;无氮浸出物含量、表观消化率和可消化无氮浸出物分别为36.64%,81.91%,33.08%。结果提示,饲料桑粉是一种营养价值较高的饲料资源。     

生长肥育猪舍的环境管理

良好的猪舍环境是维持动物健康的基础,实现养猪生产节本增效的重要途径。文章结合生长肥育猪饲养的特点,解析生长肥育猪舍环境管理的意义和作用,系统综述了猪舍地面的清洁、猪舍空气清洁度及温度和湿度的调节、适宜的光照条件、有害生物防治和其他应激源的控制等方面的技术和应用情况,对如何深化改善猪舍环境管理提出了建议。     

玉米DDGS在生长育肥猪生产中的应用研究进展

文章综述了玉米DDGS对生长育肥猪的营养价值,不同添加量对生长育肥猪生产性能的影响,以及玉米DDGS中高含量多不饱和脂肪酸对猪胴体脂肪酸组成以及碘值的影响。     

生长育肥猪呼吸道疾病的发病特点与危害

正猪只在各个阶段都容易感染呼吸道疾病,特别是在生长育肥阶段,其往往由于一系列病原微生物、环境应激和猪只自身体抗力下降等作用引起。呼吸道疾病临床上主要表现为发病猪出现体温上升、咳嗽、采食量降低、呼吸困难等症状~([1])。最近几年,国内养猪业不断发展壮大,但往往由于引种把关不严、病原微生物的突变、防疫措施落实不到位、     

Effect of group size on performance of growing-finishing pigs

Six hundred forty growing-finishing pigs (initial BW = 23.2 +/- 4.8 kg) were used in a 12-wk study (final BW = 95.5 +/- 10.2 kg) to quantify the effects of group size (10, 20, 40, and 80 pigs/pen) on performance, tail biting, and use of widely distributed feed resources. One single-space wet/dry feeder was provided for every 10 pigs, and floor allowance was 0.76 m2/pig in all treatment groups. Weight gain and feed intake were measured every 2 wk. At weighing, a tail-biting injury score was given to each pig. Blood samples were collected and analyzed for neutrophil:lymphocyte ratio before regrouping at the beginning of the experiment, 24 to 48 h after regrouping, and on the last day of each trial. The use of feeders by individual pigs was assessed by behavioral observations. Average daily gain for the entire 12-wk trial did not differ among group sizes (861, 873, 854, and 845 g/d for groups of 10, 20, 40, and 80, respectively; P > 0.10). During the first 2 wk, ADG was lower for pigs in groups of 40 (554 g/d) than pigs in groups of 10 (632 g/d; P < 0.05), but not pigs in groups of 20 or 80 (602 and 605 g/d, respectively). Average daily feed intake, feed efficiency, and variability in final BW within a pen also did not differ among group sizes. Tail-biting injury scores increased throughout the study, but did not differ among group sizes. Similar proportions of pigs were removed from the trial for health reasons, primarily due to tail biting, in all treatments. Individual pigs in each group size ate from most, if not all, of the feeders in the pen. There was no evidence of spatial subgrouping within the larger groups. The results suggest that housing growing-finishing pigs in groups of up to 80 pigs is not detrimental to productivity and health if space allowance is adequate and feed resources are evenly distributed.     

Serologic status of pseudorabies virus in growing-finishing pigs in quarantined herds

It has been reported that pseudorabies virus (PRV) stops spreading within growing-finishing sections of a large percentage of infected farrow-to-finish herds. This study was designed to follow the PRV status of growing-finishing pigs in a sample of infected herds. Fifteen infected herds were selected, of which 11 had seropositive finishing pigs and 4 had seronegative finishing pigs. These herds were visited quarterly for one year, and a cross section of growing-finishing pigs was tested for the presence of anti-PRV antibodies. The 4 herds that initially were seronegative remained seronegative, whereas of the 11 herds initially seropositive, 4 remained seropositive, 4 became seronegative, and 3 became temporarily seronegative before becoming seropositive again. Three characteristics serologic profiles were observed: one indicating continued viral spread; one indicating no spread for at least the preceding 3 months; and one indicating that PRV spread had recently ceased in this section of the herd. Results of our study indicated that periodic monitoring of a cross section of the growing-finishing pigs for their PRV serologic status was valuable for determining whether PRV was actively spreading in this section of the herd.     

Phosphorus requirements of growing-finishing pigs reared in a commercial environment

The objective of this study was to identify available phosphorus (aP) requirements of pigs reared in commercial facilities. In a preliminary study, 600 gilts (PIC) were allotted randomly to low (0.30%) or high (0.37%) dietary aP from 43 to 48 kg BW, and later to 0.19 or 0.27% aP from 111 to 121 kg BW. No differences were observed (P = 0.42 to 0.88) in ADG, but G:F from 43 to 48 kg tended to improve (P = 0.07) for pigs fed low aP. Results suggested that the aP requirement was at or below 0.30 and 0.19%. These concentrations were used to titrate aP requirements in Exp. 1 and 2. In Exp. 1, 1,260 gilts (initially 33.8 kg) were allotted randomly to one of five dietary treatments containing 0.18, 0.22, 0.25, 0.29, or 0.32% aP, corresponding to 0.5, 0.6, 0.7, 0.8, or 0.9 g of aP/Mcal of ME. There were 28 pigs per pen and nine pens per treatment. From d 0 to 14, increasing aP increased ADG (linear, P = 0.03) and G:F (quadratic, P = 0.07), with the greatest response observed as aP increased from 0.18 to 0.22% (G:F breakpoint = 0.22%). However, from d 0 to 26, no differences (P = 0.12 to 0.81) were observed for any growth traits. Pooled bending moment of the femur, sixth rib, and third and fourth metatarsals increased (linear, P = 0.007) with increasing aP. In Exp. 2, 1,239 gilts (initially 88.5 kg BW) were randomly allotted to one of five dietary treatments containing 0.05, 0.10, 0.14, 0.19, or 0.23% aP, equivalent to 0.14, 0.28, 0.39, 0.53, or 0.64 g of aP/Mcal of ME. The diet with 0.05% aP contained no added inorganic P. From d 0 to 14, increasing aP increased (linear, P = 0.008 to 0.02) ADG and G:F; however, from d 0 to 28, increasing aP had no effect (P = 0.17 to 0.74) on growth performance. Increasing aP increased (linear, P < 0.001 to 0.04) metacarpal bone ash percent and bending moment. Results suggest that 33- to 55-kg pigs require approximately 0.22% aP, which corresponds to 0.60 g of aP/Mcal of ME or 3.30 g of aP/d to maximize ADG and G:F compared with NRC (1998) estimates of 0.23%, 0.70 g of aP/Mcal of ME, and 4.27 g of aP/d for 20- to 50-kg pigs. Finishing pigs (88 to 109 kg) require at least 0.19% aP, corresponding to 0.53 g of aP/Mcal of ME or 4.07 g aP/d compared with NRC (1998) estimates of 0.15%, 0.46 g of aP/Mcal of ME and 4.61 g of aP/d for 80- to 120-kg pigs. However, the percentage of bone ash and bending moment continued to increase with increasing aP. These data also suggest that complete removal of supplemental P in diets for finishing pigs (>88 kg) will decrease ADG and G:F.     

DDGS对生长育成猪的生产性能及胴体品质的影响

本试验旨在研究DDGS对生长育成猪的生产性能和胴体品质的影响。432头体重为29.8±0.2kg的育成猪被随机分成1-9个日粮组,分别为对照组（D0）,D15-0wk,D15-3wk,D15-6wk,D15-9wk,D30-0wk,D30-3wk,D30-6wk和D30-9wk,其中D0、D15和D30分别代表DDGS在猪日粮中的百分含量;0wk、3wk、6wk和9wk代表在屠宰0、3、6和9周前分别取消DDGS在猪日粮的添加时间。结果显示,当生长育成猪日粮中的DDGS含量为15%或30%时,不管屠宰前是否取消DDGS的添加,除了D30-0wk处理组的猪的ADG比对照组（D0）稍降外（0.87：0.92kg/d;P〈0.05）,其他处理组猪的ADG、ADFI和G：F均没有显著差异（P=0.76）。DDGS的不同含量或屠宰前取消DDGS的添加时间（0周、3周、6周和9周）对猪胴体质量、背最长肌（LM）猪肉品质、背脂和腹脂颜色评分分数没有显著影响（背脂,P=0.47;腹脂,P=0.17）。相对对照组,D30-0wk组的腹部猪肉嫩度稍低（P=0.04）,其他处理组猪的腹部猪肉嫩度与对照组的差别均不大（P=0.26）。当增加猪日粮中的DDGS含量时,腹脂的亚油酸含量（C18：2;P〈0.001）和碘值（IV;P〈0.001）有所增加。当猪日粮中含有15%DDGS时,在屠宰前的0～9周取消DDGS添加可以线性的降低猪腹脂的C18：2含量和腹脂碘值（屠宰前的第0-、3-、6-和9周的腹脂C18：2含量分别为：14.6%、13.3%、12.6%、10.9%;P=0.001;碘值分别为：67.3、64.4、64.1和62.7）;而当猪的日粮中含有30%DDGS时,在屠宰前0～9周取消DDGS的添加也可以线性的降低猪腹脂的C18：2含量和腹脂碘值（屠宰前的第0-、3-、6-和9周的腹脂C18：2含量分别为：17.3%、16.1%、14.2%和12.4%;P〈0.001;碘值分别为：71.2、68.2、64.5和62.7）。总体来看,当在生长育肥猪中添加高达30%DDGS对猪的生产性能有极小影响,且在屠宰前的3周取消在猪日粮中的DDGS的添加可以降低猪腹脂的C18：2含量和碘值。     

Effect of conjugated linoleic acid on energy metabolism in growing-finishing pigs

The effect of conjugated linoleic acid (CLA) on energy metabolism was studied in a respiration experiment with 20 growing pigs. From 70 kg liveweight onwards the animals received isoenergetic rations containing 0 or 3% CLA on the basis of metabolic bodyweight. Between 95 and 100 kg liveweight the gas exchange of each animal was measured over 48 h in a respiration chamber. This was preceded by a 5‐day quantitative determination of faeces and urine. The heat production and energy retention of the animals were determined by the carbon–nitrogen balance technique and the RQ method. Additionally several parameters of blood serum were determined. CLA had no effect on digestibility and metabolizability of energy, nor were gas exchange and heat production (HP) of the animals affected by the treatment. Average heat production across all measurements was 628 kJ/kg W^0.75 in the control group and 636 kJ/kg W^0.75 in the CLA group. No difference in fat deposition was observed (control 386, CLA group 379 kJ/kgW^0.75). The N balance on the other hand was 2.2 g/day higher in the CLA‐supplemented animals. This caused retained protein energy, as a proportion of total energy retention, to increase from 24.2 to 25.8%. The ratio of retained protein energy to fat energy was 10% higher in the CLA‐treated animals than in the controls. Body mass increase over the trial as a whole was unaffected (control 27.6, CLA group 28.1 kg, equivalent to daily gains of 931 and 946 g, respectively). Blood serum lipoproteins exhibited few CLA‐induced changes. The greatest effects were observed in triacylglycerols, which were raised in the CLA animals compared with the controls. The ratio of cholesterol‐low‐density lipoprotein to cholesterol‐high‐density lipoprotein rose by 17% as a result of CLA treatment. Serum concentrations of albumin, creatinine, urea and glucose were unchanged. In conclusion, the study showed that supplementation with CLA under isoenergetic feeding conditions with a strongly positive energy balance has no marked effect on total metabolism, although a slightly enhanced deposition of protein was evident.     

那西肽对生长肥育猪的作用效果及其在产品中的残留

选择32头30kg左右健康的二元杂交生长猪, 随机分为4组, 每组8头, 个体饲喂, 4组均喂相同的基础饲粮, 但添加不同饲用抗生素,分别是低、高剂量那西肽(10mg/kg、50mg/kg)、盐霉素(30mg/kg) 和对照。猪体重达90kg时, 分别按0、3和7d停药后屠宰, 检测那西肽在样品各器官中的残留量。结果表明: 那西肽可显著提高生长肥育猪的采食量和日增重(P<0 05), 但是对料重比的改善作用不明显; 当检测灵敏度为0 01mg/kg时, 在低、高剂量那西肽组猪的心脏、肝脏、肾脏和背最长肌中, 均未检出那西肽。     

Development of sustainable precision farming systems for swine: estimating real-time individual amino acid requirements in growing-finishing pigs

The objective of this study was to develop and evaluate a mathematical model used to estimate the daily amino acid requirements of individual growing-finishing pigs. The model includes empirical and mechanistic model components. The empirical component estimates daily feed intake (DFI), BW, and daily gain (DG) based on individual pig information collected in real time. Based on DFI, BW, and DG estimates, the mechanistic component uses classic factorial equations to estimate the optimal concentration of amino acids that must be offered to each pig to meet its requirements. The model was evaluated with data from a study that investigated the effect of feeding pigs with a 3-phase or daily multiphase system. The DFI and BW values measured in this study were compared with those estimated by the empirical component of the model. The coherence of the values estimated by the mechanistic component was evaluated by analyzing if it followed a normal pattern of requirements. Lastly, the proposed model was evaluated by comparing its estimates with those generated by the existing growth model (InraPorc). The precision of the proposed model and InraPorc in estimating DFI and BW was evaluated through the mean absolute error. The empirical component results indicated that the DFI and BW trajectories of individual pigs fed ad libitum could be predicted 1 d (DFI) or 7 d (BW) ahead with the average mean absolute error of 12.45 and 1.85%, respectively. The average mean absolute error obtained with the InraPorc for the average individual of the population was 14.72% for DFI and 5.38% for BW. Major differences were observed when estimates from InraPorc were compared with individual observations. The proposed model, however, was effective in tracking the change in DFI and BW for each individual pig. The mechanistic model component estimated the optimal standardized ileal digestible Lys to NE ratio with reasonable between animal (average CV = 7%) and overtime (average CV = 14%) variation. Thus, the amino acid requirements estimated by model are animal- and time-dependent and follow, in real time, the individual DFI and BW growth patterns. The proposed model can follow the average feed intake and feed weight trajectory of each individual pig in real time with good accuracy. Based on these trajectories and using classical factorial equations, the model makes it possible to estimate dynamically the AA requirements of each animal, taking into account the intake and growth changes of the animal.     

Water intake and wastage at nipple drinkers by growing-finishing pigs

Three experiments were conducted to assess water intake, water wastage, and a means to decrease water wastage by growing-finishing pigs from nipple drinkers. In Exp. 1, 48 pigs were studied during two periods (average BW = 53 and 72 kg for Period 1 and 2, respectively). Water disappearance and wastage were determined for 4 d, while nipple drinkers were set at 50 mm above the shoulder height of the smallest pig in the pen (recommended heights), with flow rates at 700 mL/min during Period 1, and 1,000 mL/min during Period 2. Water intake rate was assessed at two nipple flow rates, approximately 650 and 1,300 mL/min during the Period 1, and 1,000 and 2,000 mL/min during the Period 2. The average water intake was 4.01 and 5.38 +/- 0.19 L.pig(-1).d(-1) during Periods 1 and 2, respectively (P < 0.01). Water wastage as a percentage of water disappearance was similar between the two periods (25.8 and 27.0 +/- 1.9% for Periods 1 and 2, respectively). Water intake rate was 467 and 795 mL/min (+/-34.2; P < 0.01) during Period 1, and 722 and 1,422 mL/min (+/-80.0; P < 0.01) during Period 2, at the lower and higher flow rates, respectively. In Exp. 2, 32 pigs were used in a 2 x 2 factorial design to determine effects of nipple heights (recommended vs. unadjusted = 330 mm) and flow rates (500 vs. 1,000 mL/min) on water intake and wastage. Water wastage was increased (P < 0.01) on the unadjusted vs. recommended nipple height, and the higher flow rate also resulted in greater wastage (P = 0.03) compared with the lower rate. In Exp. 3, water disappearance and manure output in 16 pens of 18 pigs per pen were monitored for 12 wk (average initial BW = 32 kg) using four drinker treatments (bowl drinker, nipple drinker at recommended heights, an unadjusted nipple set at 480 mm, and high nipple drinker height of 730 mm with a step underneath). For pigs on the high nipple drinker, the average water disappearance and manure output did not differ from those of the pigs on the recommended nipple heights and bowl drinker, but these measurements were 15 and 12% lower, respectively, than for the pigs on the low nipple drinker. The results indicate that growing-finishing pigs can maintain adequate water intake from a variety of drinker types and management. Water wastage can be controlled through drinker management.     

Performance,health and behaviour of organic growing-finishing pigs in two different housing systems with or without access to pasture

Abstract

The effects of two housing systems (deep litter and straw-flow), with and without access to pasture during the summer period, were studied in an organic growing-finishing pig herd. Performance, health, skin lesions and daytime pig activity were studied in 29 pens of 16 pigs (total of 464 pigs, in 4 batches). Data from 21 pens were used for comparisons of deep litter and straw-flow and data from 16 pens for comparisons of access/no access to pasture. Pigs in the deep litter system had a lower carcass meat percentage (56.6% vs. 57.3%) and more locomotion problems (4.4% vs. 0%) than pigs in the straw-flow system. No difference in daytime pig activity was detected between the two housing systems. Under moderate temperatures, pigs with access to pasture and fed a commercial organic feed inside the building were not more active during daytime behaviour studies (7.30?h–16.30?h) than pigs without access to pasture. However, at 17 weeks of age the pigs with pasture access spent 21% of their time on pasture, less time inside the pig house (20% vs. 33%) and less time on the outside concrete area (4% vs. 12%) than the pigs without pasture. No difference in performance was detected between pigs with and pigs without access to pasture.