Performance,carcass and technological meat quality of pigs in indoor and outdoor production systems

Abstract

This study aimed to compare different production systems, i.e., the combined effect of outdoor and indoor rearing of pigs and organic diets fed ad libitum or restrictively. Furthermore, the suitability of two breed crosses for outdoor rearing was studied. The effects on performance, carcass and technological quality traits were investigated. During two years, 240 pigs of Duroc x Large White (D*LW) and Swedish Landrace x Large White (L*LW) were allocated to three production systems: 1) Pigs kept outdoors, fed an organic diluted diet (20% alfalfa roughage) ad libitum; 2) Pigs kept outdoors, strategically fed a diluted organic diet up to a live weight of approximately 80 kg and thereafter an undiluted organic diet ad libitum; 3) Pigs kept indoors, fed an undiluted organic diet restrictively. For outdoor pigs, strategic feeding increased daily weight gain and backfat thickness, compared with feeding a diluted diet throughout (p≤0.01). L*LW pigs in both outdoor systems grew slower than in the indoor system (p≤0.001), whereas for D*LW pigs only outdoor pigs fed the diluted diet had a slower growth rate. Outdoor pigs had lower dressing percentage than indoor pigs. Glycogen content and L* values in M. longissimus dorsi were higher, whereas b* values were lower in meat from pigs in the indoor system. D*LW pigs had higher water-holding capacity (lower drip, thawing and cooking losses), lower shear force and higher intramuscular fat content compared with L*LW pigs.     

Phytase improves iron bioavailability for hemoglobin synthesis in young pigs.

Dietary phytase supplementation improves bioavailabilities of phytate-bound minerals such as P, Ca, and Zn to pigs, but its effect on Fe utilization is not clear. The efficacy of phytase in releasing phytate-bound Fe and P from soybean meal in vitro and in improving dietary Fe bioavailability for hemoglobin repletion in young, anemic pigs was examined. In Exp. 1, soybean meal was incubated at 37 degrees C for 4 h with either 0, 400, 800, or 1,200 units (U) of phytase/kg, and the released Fe and P concentrations were determined. In Exp. 2, 12 anemic, 21-d-old pigs were fed either a strict vegetarian, high-phytate (1.34%) basal diet alone, or the diet supplemented with 50 mg Fe/kg diet (ferrous sulfate) or phytase at 1,200 U/kg diet (Natuphos, BASF, Mt. Olive, NJ) for 4 wk. In Exp. 3, 20 anemic, 28-d-old pigs were fed either a basal diet with a moderately high phytate concentration (1.18%) and some animal protein or the diet supplemented with 70 mg Fe/kg diet, or with one of two types of phytase (Natuphos or a new phytase developed in our laboratory, 1,200 U/kg diet) for 5 wk. In Exp. 2 and 3, diets supplemented with phytase contained no inorganic P. In Exp. 1, free P concentrations in the supernatant increased in a phytase dose-dependent fashion (P<.05), whereas free Fe concentrations only increased at the dose of 1,200 U/kg (P<.10). In Exp. 2 and 3, dietary phytase increased hemoglobin concentrations and packed cell volumes over the unsupplemented group; these two measures, including growth performance, were not significantly different than those obtained with dietary supplemental Fe. In conclusion, both sources of phytase effectively degraded phytate in corn-soy diets and subsequently released phytate-bound Fe from the diets for hemoglobin repletion in young, anemic pigs.     

Computer simulation model of swine production systems: I. Modeling the growth of young pigs

Theoretical concepts and relationships were used to develop a deterministic pig growth model. The model predicts, in a continuous form, growth and body composition of boars, barrows, and gilts according to genotype, diet, and management conditions. The model is aggregated at the whole-animal level with three main elements of body composition; total body DNA, total body protein mass (PT), and total body mass of lipids, with PT determining the secondary elements of ash and moisture. The primary factors regulating growth were associated with cellular hyperplasia and hypertrophy in agreement with the basic concepts described by Baldwin and Black (1979). Differential equations representing DNA accretion and protein synthesis and degradation were adapted from Oltjen et al. (1985). Normal pig protein growth was characterized from published data. Body PT was used to reflect several metabolic activities related to animal size and age, as in some prior models. Dietary energy and protein were used in sequence until requirements are satisfied, first for maintenance, then for protein growth, and finally for fat deposition. A comparison between experimental and simulated results illustrates that the model may simulate growth and body composition of young pigs adequately.     

The effects of genotype and selected environmental factors on colostrum production and intake in cattle

The aim of this study was to determine effects of genotype and selected environmental factors on colostrum production, intake, and efficiency in the cattle. The investigations were conducted on 67 dam-calf pairs. All cows were of Polish Holstein-Friesian breed, the Black-and-White variety (PHF-HO), whereas calves were sired by bulls of the following breeds: PHF-HO, Polish Holstein-Friesian of the Red-and-White variety (PHF-RW), Jersey (JE), Montbéliarde (MB) and Limousine (LI). The colostrum was collected from cows and offered to calves "from bucket" thrice a day. The amount of produced colostrum considerably exceeded the ability of its consumption by calves. Low share of HF genes in the cow, older cow's age and calving in the period from January to April appeared to be favorable factors for colostrum production. Calves born to cows with low HF gene share drank more colostrum than calves originating from cows with higher gene share of this breed. Crosses with JE drank the highest amount of the colostrum in relation to body weight, while MB-sired calves drank the highest amount in absolute terms. Colostrum intake was positively correlated with the dam's age. Furthermore, it was shown that in case of the first colostrum intake the most favorable period was from May to September, while in cases of total intake in the first day of life and mean intake in the first 5 days of life it was the period from January to April. Crosses with JE were characterized by extremely high use of colostrum per unit of body weight gain.     

Toxic effects of supplemental copper and roxarsone when fed alone or in combination to young pigs

Three experiments were conducted to investigate the roxarsone (3-nitro-4-hydroxyphenylarsonic acid) X copper (Cu) interaction in weanling pigs. Supplemental roxarsone at 400 mg/kg diet decreased rate and efficiency of weight gain and caused visible neurological signs of toxicosis. Copper addition (CuSO4 X 5H2O) at a level of 650 mg Cu/kg diet likewise decreased weight gain and feed efficiency, and it also increased hepatic Cu deposition. The combination of these growth-depressing dosages of roxarsone and Cu resulted in a far greater reduction in gain and efficiency of feed utilization than was the case when either compound was fed alone. A growth-promoting dosage of Cu (250 mg/kg) increased weight gain by 32% in one experiment but showed no efficacy in alleviating the growth-depression resulting from feeding 400 mg/kg roxarsone. A roxarsone dosage of 100 mg/kg increased gain and feed efficiency. Surprisingly, the decreased weight gain in pigs fed 650 mg/kg Cu was ameliorated by feeding 100 mg/kg roxarsone concomitantly. This level of roxarsone also reduced liver Cu concentration substantially. It thus appears that the nature of the roxarsone X Cu interaction is dependent on the dose of each compound administered. Moreover, low-dose roxarsone administration appears to ameliorate Cu toxicity, but low-dose Cu feeding does not show efficacy against roxarsone toxicity.     

Immunogenic properties and mycoplasmal pneumonia of swine (MPS) lung lesions in Large White pigs selected for higher peripheral blood immune capacity

Immunogenic properties and mycoplasmal pneumonia of swine (MPS) lung lesions were compared between the immunity‐selected Large White line and the non‐selected Large White line. The selected Large White line showed a higher level of pulmonary MPS lesions compared with the non‐selected Large White line. Subsequent to vaccination, the percentage of natural killer cells and T cells (CD3⁺CD4⁺CD8^‐ and CD3⁺CD4^?CD8⁺ T cells) were significantly increased in the non‐selected line but remained unchanged in the immunity‐selected Large White line. Secretion of Mycoplasma hyopneumoniae vaccine‐specific immunoblogulin G and phagocyte activity in peripheral blood were significantly higher in the immunity‐selected Large White line than in the non‐selected line. Expression of interleukin (IL)‐4 and IL‐6 messenger RNA in hilar lymph nodes was significantly lower in the immunity‐selected Large White line than in the non‐selected line. However, expression of IL‐10 in all immune tissues was significantly higher in the immunity‐selected Large White line. These results suggest that the selection for high immunity was not effective in increasing resistance to MPS lung lesions.     

Effect of injected and dietary iron in young pigs on blood hematology and postnatal pig growth performance

The relationship of injected Fe doses on blood hematology and pig growth performance during both preweaning and postweaning periods was studied. In Exp. 1, the effect of BW of 347 pigs injected with 200 mg of Fe (dextran) intramuscularly (i.m.) at birth on hemoglobin (Hb) and percent hematocrit (Hct) at weaning was assessed. As BW increased there was a decline (P < 0.01) in Hb and Hct. In Exp. 2, Fe injection doses and timing of injected Fe on blood hematology and pig growth were evaluated. Injections were as follows: 1) 200 mg of Fe at birth; 2) 300 mg of Fe at birth; or 3) 200 mg of Fe at birth + 100 mg of Fe at d 10. A total of 269 pigs were allotted within litter to 3 treatments. The 2 greater quantities of injected Fe (i.e., 300 or 200 + 100 mg of Fe) had similar but greater (P < 0.05) Hb and Hct values than pigs receiving 200 mg of Fe, but growth rates were similar at weaning. The effects of injecting 200 mg of Fe at birth and either saline or 100 mg of Fe at 10 d of age were investigated in Exp. 3. Weaned pigs of each group were fed diets with 0, 80, or 160 mg/kg of added Fe for 35 d as a 2 × 3 factorial arrangement with 12 replicates (n = 360 pigs) in a randomized complete block design (RCB). The innate Fe contents of diets averaged 200 mg/kg. The greater Fe injection group (200 + 100 mg) had greater (P < 0.01) Hb and Hct values through 14 d postweaning (P < 0.05) and greater (P < 0.01) Hct values through 21 d postweaning. As dietary Fe increased, Hb was greater only at d 14 (P < 0.05 4), whereas Hct increased linearly to d 35 (P < 0.01) postweaning. Dietary Fe resulted in linear increases (P < 0.01) in ADG from d 21 to 35 and d 0 to 35. In Exp. 4, 3 dietary Fe (80, 160, and 240 mg/kg of diet), 2 injected Fe treatments (200 or 300 mg of Fe) at birth, and birth BW (<1.5 or ≥1.5 kg) were evaluated as a 2 × 2 × 3 factorial arrangement of treatments in a RCB design with 6 replicates (n = 280 pigs). The 300 mg of Fe injection group had lighter BW in both birth BW groups, with a birth BW × injected Fe interaction (P < 0.01). This resulted in the lighter birth BW pigs receiving 200 mg of Fe having greater BW gains to 240 mg/kg of dietary Fe, whereas light birth BW pigs injected with 300 mg of Fe plateaued at 160 mg/kg of Fe. Pigs in the heavy birth BW group injected with 200 or 300 mg of Fe at birth responded similarly to dietary Fe postweaning. These results indicate that blood Hb and Hct were affected by pig BW at weaning, but the additional 100 mg of Fe i.m. at 10 d of age increased blood hematology and that Fe injected preweaning affected initial postweaning performance.     

Welfare and production implications of teeth clipping and iron injection of piglets in outdoor systems in Scotland

To assess the merits of implementing piglet husbandry tasks in outdoor systems, 550 piglets in 49 litters were used in a split-plot experiment to determine the effects of (a) leaving piglet teeth intact or clipping them at birth in alternate litters, and (b) injecting alternate piglets within each litter with 200 mg of iron (as dextran) at 2–4 days after farrowing or leaving piglets untreated. Leaving teeth intact increased facial lesion scores at 7 days, 14 days and weaning (22 days) but had no effect on survival or daily liveweight gain. No udder damage was recorded on sows and no behavioural differences in time spent away from the farrowing hut or willingness to be suckled were observed. Administration of iron resulted in a small but significant elevation in piglet blood haemoglobin level at weaning, but had no significant effect on piglet performance. All piglets had blood haemoglobin levels in excess of 6 g 100ml⁻¹. A survey of 90 other untreated piglets from nine different herds in northeastern Scotland failed to detect any anaemic piglets. There was no overall correlation between herd mean haemoglobin level and soil iron content, although the lowest levels of both occurred in the same herd. Implementation of these husbandry tasks is seldom likely to be justified in outdoor systems in northeastern Scotland.     

The effect of recombinant swine interleukin-4 on swine immune cells and on pro-inflammatory cytokine productions in pigs

The in vitro effect and the in vivo influence of recombinant swine IL-4 (rSwIL-4) were characterized in various swine cells and in nursery pigs on LPS-induced endotoxic shock and pro-inflammatory cytokine productions. In in vitro experiment, the rSwIL-4 induced a proliferation of CD4 positive T cells in mitogen-prestimulated peripheral blood mononuclear cell (PBMC). In addition, the rSwIL-4, which was produced from insect cells, promoted the differentiation of monocytes into immature dendritic cells in combination with granulocyte macrophage-colony stimulating factor (GM-CSF). Furthermore, the rSwIL-4 successfully suppressed the LPS-induced secretion of TNF-alpha, IL-1alpha, IL-6, IL-8, and IL-18 from swine alveolar macrophages when rSwIL-4 was treated at the same time with LPS. In in vivo experiment in nursery pigs, subcutaneous pretreatment of rSwIL-4, which was produced from baculovirus expression system, enhanced the severity of respiratory failure with endotoxic shock, and increased the production of TNF-alpha and IL-18 in response to inoculation with LPS. These results indicate that the rSwIL-4 is biologically active in both in vitro and in vivo treatments. Depending on the administration time, pro-inflammatory cytokine productions by IL-4 can cause either inhibitory or stimulatory regulation.     

Computer simulation model of swine production systems: II. Modeling body composition and weight of female pigs, fetal development, milk production, and growth of suckling pigs

Theoretical concepts and relationships used to develop a deterministic computer simulation model of female pigs during their reproductive life are described. The model predicts, in a continuous form, body composition and weight of female pigs, fetal development, sow milk yield, and growth of suckling pigs according to genotype, diet, and management conditions. The model simulates growth of adult female pigs. Dietary nutrients are used first for maintenance and second for fetal growth or milk production. Any surplus is retained in the body. Energy and protein body reserves are mobilized when a nutrient deficit occurs during gestation or lactation. However, the rates of body protein and fat accretion as well as the fat/protein ratio are limited by boundaries, the values of which depend on the nutritional and physiological status of the pig. The model's ability to simulate sow body weight changes and composition, fetal growth, milk production, and suckling pig's growth is illustrated.     

血红蛋白粉对仔猪血液中血红蛋白、铁及转铁蛋白含量的影响

选择35日龄、体重相近的杜×长×大三元杂交仔猪84头,按遗传基础相似、公母各半的原则,随机分成4组,第I组为对照组,其余为试验组,每个处理组设3个重复,分别用0%、1%、2%、3%的血红蛋白粉替代其日粮中相应比例的鱼粉(其中试验Ⅲ组中替代2%的鱼粉和1%的豆粕),并进行了为期30d的饲养试验。试验结果表明,仔猪的日增重试验Ⅱ组和试验Ⅲ组显著高于试验Ⅰ组和对照组(P<0.05),且试验Ⅲ组显著高于试验Ⅱ组(P<0.05);仔猪的血红蛋白浓度随血红蛋白粉添加量的增加而成正相关;仔猪血浆中转铁蛋白的含量随日粮中血红蛋白粉添加比例的增加而上升,并且各组间差异是显著的(P<0.05);仔猪的血浆铁含量试验Ⅲ组显著高于其它组(P<0.05)。     

The effects of vomitoxin and feed intake on the performance and blood characteristics of young pigs

Thirty barrows (average weight 8.4 kg) were used in a 3-wk experiment to determine the effects of the ingestion of vomitoxin (deoxynivalenol)-contaminated feed on performance and blood chemistry. The barrows were assigned randomly to consume either: 1) a control diet (C), fed ad libitum, 2) a vomitoxin contaminated diet (V; 10.5 ppm), fed ad libitum, or 3) a vomitoxin contaminated pair-fed at levels equal to those consumed by V animals (PF). The V and PF pigs had similar daily gains (.19 vs .20 kg) and feed intakes (.40 and .39 kg), but both of these were lower (P less than .01) than those for the C-fed pigs (.38 kg daily gain and .72 kg feed intake). The V-fed pigs had lower (P less than .05) hematocrit, hemoglobin, serum glucose and serum phosphorus and tended to have lower serum calcium (P less than .06) than C-fed pigs. The V-fed pigs had higher (P less than .05) hemoglobin and tended to have higher (P less than .08) serum phosphorus and lower (P less than .07) serum calcium than PF animals. There was a high total- and free-bilirubin concentration in serum of C- and V-fed pigs in the last sampling period (3-wk), which may be due to fasting and not cholestasis. No differences among treatments were observed in any of the other blood parameters. These results suggest that the differences in animal performance and blood parameters observed between control-and vomitoxin-fed pigs are mainly due to differences in feed intake.     

Effects of mycoplasmal pneumonia of swine (MPS) lung lesion‐selected Landrace pigs on MPS resistance and immune competence in three‐way crossbred pigs

To clarify the genetic influence of mycoplasmal pneumonia of swine (MPS) lesion‐selected Landrace (La) on MPS resistance and immune characteristics in three‐way crossbred pigs (LaWaDa), the LaWaDa pigs were compared with the non‐selected crossbred (LbWbDb) and purebred (La) pigs. The MPS lesion score in the three lines was as follows: La line < LaWaDa line < LbWbDb line, with significant differences among the lines. The proportions of myeloid cells and T cells were lower and higher, respectively, in the LaWaDa pigs compared with those in the other two lines. Messenger RNA (mRNA) expression of interleukin (IL)‐6, IL‐10, transforming growth factor‐β, and interferon‐γ in peripheral blood was significantly increased after vaccination in the La and LaWaDa lines. IL‐4 mRNA expression in the LaWaDa line was intermediate to the La and LbWbDb lines. Furthermore, principal component analysis for immune traits and MPS lesions was executed to clarify the characteristics of each pig line. These findings suggest that the immune responses in the three pig lines are genetically distinct and that MPS resistance and some immunity characteristics from the La line were transmitted to the three‐way crossbred pigs.     

Metabolic utilization of energy and maintenance requirements in growing pigs: effects of sex and genotype.

An experiment was conducted in which the metabolic utilization of energy was measured in individually penned pigs from seven groups that differed in genotype and(or) sex and ranged in body weight between 20 and 107 kg. The animals were fed a diet containing, on a DM basis, 14.7 MJ ME and at least 21% CP. Heat production was measured in an open-circuit calorimeter, and energy, nitrogen, and fat balances were determined at regular intervals over the growing period; a total of 177 measurements were performed. Body composition of the animals was measured by serial slaughter, and these data were used for estimating the body composition of an animal at a given weight through allometric regression. A factorial analysis procedure was used to estimate the utilization of ME by regressing the ME intake on the observed protein and lipid deposition rates. The intercept of this equation is the maintenance energy requirement (MEm) and was represented either as a function of body weight with group-specific parameters (MEm = a(i) BWb) or as a function of the muscle and visceral mass with an additional additive group effect (MEm = aM muscle(b) + a(v) viscera(b) + G(i)). With BW as dependent variable, the exponent b was close to .60 and differed significantly from .75. The regression coefficient (a(i)) averaged 1.02 MJ ME/kg.60 but it was different for most groups, indicating that different groups of animals have different maintenance requirements. Fixing the exponent to .75 consistently underestimated the maintenance requirement. When the exponent b was not fixed to .75 but estimated, the partial efficiencies for protein and lipid deposition were .62 and .84, respectively. Body muscle and visceral mass could explain a large part of the variation in MEm. Viscera contributed three times more to MEm (per kilogram of mass raised to the .70 power) than did muscle. Even though the muscle mass exceeds to a large extent the visceral mass in animals, the contribution of muscle to MEm was lower than that of viscera for most groups.     

Ascariasis, respiratory diseases and production indices in selected Prince Edward Island swine herds.

The levels of production, ascarid burden and respiratory disease were measured on 15 purposively selected swine herds, and the relationships between the various measures of ascarid burden were examined. On each farm 30 randomly selected pigs were weighed and rectal fecal samples were collected at approximately 11, 15, 19 and 22 weeks of age, and at slaughter. Fecal ascarid-egg counts and duration of infection were combined to calculate a composite measure of ascarid burden called "lifetime burden". At the abattoir the carcass weight and levels of anteroventral pneumonia, atrophic rhinitis, and liver lesions were recorded for each hog. The number of ascarids in the small intestines were counted. Study hogs were marketed at an average of 189 +/- 22 days. The average dressed carcass weight was 77.0 +/- 5.9 kg and the mean average daily gain was 0.519 +/- 0.071 kg/day. The percent of hogs with ascariasis varied widely among farms, no matter what measure of ascariasis was used; the percent with intestinal ascarids at slaughter ranged from 0% to 96%, the percent that shed ascarid eggs during their lifetime ranged from 0% to 100%, and the range for hogs with liver lesions ranged from 27% to 100%. Of the hogs slaughtered, 82% had milk spot lesions, 32% shed ascarid eggs during their lifetime and 35% had intestinal ascarids. The latter had an average of 12 intestinal ascarids. Anteroventral pneumonia occurred in 55% of the slaughtered hogs and 9% had atrophic rhinitis scores of five. The percent of hogs per farm with pneumonia ranged from 17% to 96%. The percent of hogs per farm with atrophic rhinitis scores of five ranged from 0% to 57%.     

Urea cycle metabolism: effects of supplemental ornithine or citrulline on performance, tissue amino acid concentrations and enzymatic activity in young pigs fed arginine-deficient diets

Two experiments were conducted with young pigs to determine the efficacy of ornithine (Orn) or citrulline (Cit) as precursors of arginine (Arg). In Exp. 1, pigs were individually fed an Arg-deficient, semipurified diet (.18% Arg) supplemented with .3% Arg or an equimolar quantity of Orn or Cit. Supplemental Arg or Cit increased rate and efficiency of weight gain, but Orn addition was without effect. Free Arg in plasma 3 h post-prandial was increased by addition of either Arg or Cit to the basal diet. Liver Arg was elevated by dietary addition of Arg, Orn or Cit; kidney Arg and Orn were elevated only in pigs receiving supplemental Cit. Arginine or Cit addition to the diet increased Arg concentration in muscle tissue, but muscle Orn was unresponsive to any of the supplements fed. In Exp. 2, pigs were again fed the Arg-deficient, semipurified diet supplemented with .3% Arg or four times an isomolar quantity of ornithine. Arginine addition to the diet increased weight gain and feed efficiency, while Orn supplementation was without effect. Plasma Orn was increased by excess Orn, while plasma Cit was unaffected by supplemental Arg or Orn. Moreover, excess Orn increased free Orn and proline (Pro) in liver, kidney and muscle. Free Cit, however, increased only in liver from feeding excess Orn. In addition, excess Orn decreased both plasma ammonia and free glutamine (Gln) concentration in brain. Arginase activity was roughly 10, 40 and 100 times greater in hepatic tissue than in renal cortex, renal medulla or intestinal mucosa, respectively, while hepatic ornithine transcarbamoylase (OTC) activity was about 15 times greater than the activity present in mucosa tissue. Renal OTC activity was too low to be accurately measured.