Relationship to growth performance of pneumonia and atrophic rhinitis lesions detected in pigs at slaughter among four seasons.

A commercial swine herd was selected for study, because pigs at slaughter repeatedly had lung lesions consistent with enzootic pneumonia and had snout lesions typical of atrophic rhinitis. Pigs born during various seasons of the year were allotted to 4 investigations and were evaluated from birth to slaughter. Individual lungs and snouts were identified and collected at the slaughter plant and later examined for gross lesions of bronchopneumonia and atrophic rhinitis, respectively. Each lesion was scored, and the following comparisons were made within investigations: prevalence and mean scores for lung lesions; prevalence and mean grades for snout lesions; correlations between lung lesion scores and growth indicators; correlations between snout lesion grades and growth indicators; and correlations between lung lesion scores and snout grade scores. Included in the growth indicators were average daily gain during the growing phase, average daily gain during the finishing phase, average daily gain during growing and finishing phases, and days to attain 104.5 kg of body weight. Prevalence of lung or snout lesions, mean values for lung lesion scores, mean values for snout lesion grades, and mean values for the various growth indicators were tested for statistical differences among the 4 investigations. Prevalence of lung lesions was highest (96%) for winter-slaughtered and lowest (81%) for autumn-slaughtered pigs. Mean scores for lung lesions were 7% (summer), 5% (autumn), 9% (winter), and 16% (spring). Prevalence of snout lesions was highest (85%) for spring-slaughtered pigs and lowest (42%) for autumn-slaughtered pigs.(ABSTRACT TRUNCATED AT 250 WORDS)     

Association between growth indicators and volume of lesions in lungs from pigs at slaughter.

Conflicting findings exist among studies on the effect of pneumonia on growth in pigs. We determined the extent of pneumonia in market-weight pigs by use of an objective, volumetric method and linear regression analyses of mean daily gain and days-to-slaughter weight on the percentage of pneumonic lung. In a range of extent of pneumonia between 1.33 and 70.44%, a 10% increase in the volume of pneumonic lung was associated with a decrease in mean daily gain by 41.1 g and a 16.7-day increase in number of days to a slaughter weight of 104.5 kg.     

Field efficacy of a combined use of Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae vaccines in growing pigs

The effectiveness of simultaneous administration of commercial Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae vaccines was tested in an indoor commercial piggery which had experienced continuing respiratory-disease problems confirmed as due to both of these pathogens. Piglets were randomly assigned in equal numbers to vaccination and control groups, and each vaccine was administered at a separate site to assigned piglets at two and four weeks of age. Live weight of vaccinates immediately prior to slaughter was 2.49 kg higher (p = 0.04) than for controls at equal mean slaughter age of 132 days. Average daily gain (ADG) from 16 weeks to slaughter of vaccinates was also significantly higher (33 g/day) than in controls (p = 0.05). Daily gain was not significantly different in younger age groups. Active enzootic pneumonia lesions were more likely in control than in vaccinated pigs. There were no significant differences between vaccination groups with regard to severity of pleurisy or presence of pleuropneumonia lesions at slaughter. Log-linear modelling was used to test the statistical association between vaccination, enzootic pneumonia lesions, pleurisy lesions and pleuropneumonia lesions. It showed a reduction in the severity of enzootic pneumonia lesions for vaccinated pigs, and the presence of pleuropneumonia lesions increased the likelihood of pleurisy lesions. No other association was significant, and no evidence of synergy between the vaccines in influencing lesion severity for pleuropneumonia was detected (within the limitations set by the trial design).     

Relationship of growth performance to pneumonia and atrophic rhinitis detected in pigs at slaughter

Three commercial swine herds were selected for study, because pigs at slaughter consistently had lung lesions typical of bronchopneumonia and snout lesions consistent with atrophic rhinitis. Pigs were reared in the conventional system for each herd except that they were identified at birth and weighted at various intervals. At slaughter, individual pig lungs and snout were examined for lesions of pneumonia and atrophic rhinitis, respectively. Lesions were scored and correlated with growth indicators for each pig. Included in the growth indicators were: average daily gain (growing phase), average daily gain (finishing phase), average daily gain (total), and days to reach 104.5-kg body weight. Additionally, for each pig, scores for lung lesions were correlated to grades for snout lesions. Three correlation coefficients for measurements of pigs within herd B were significant and included days to 104.5-kg body weight and grades for snout lesions, -0.15 (P less than 0.02); average daily gain (finishing) and grades for snout lesions, 0.17 (P less than 0.01); and average daily gain (total) and grades for snout lesions, 0.16 (P less than 0.01). Contrary to findings in other investigations, pigs that attained market weight at the youngest age did not have the lowest score for lung lesions, the lowest grade for snout lesions, or the least extensive or severe lesions. Combining data from all 3 herds, the mean scores for lung lesions and mean grades for snout lesions decreased significantly (P less than 0.05) as the age of pigs at slaughter increased. All other statistical correlations were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)     

Association of growth performance with atrophic rhinitis and pneumonia detected at slaughter in a conventional pig herd in Hungary

The influence of atrophic rhinitis (AR) and pneumonia on growth performance was assessed in a conventional farrow-to-finish pig farm affected by both diseases. All tested pigs (n = 138) were individually weighed at birth, at weaning, at moving to the growing/finishing unit, and at slaughtering. The extent (grade) of turbinate atrophy and lung consolidation attributable to pneumonia was determined in each pig at slaughter. A negative correlation was found between birth weight and the prevalence of nasal lesions at slaughter, suggesting that pigs born with smaller weight may be more susceptible to AR. The growth performance of the pigs also showed a negative correlation with the degree of turbinate atrophy. In the nursery period, the average daily gain (ADG) of pigs with moderate/severe turbinate atrophy was 13.3% lower than that of animals with healthy snouts. In the finishing period, pigs with mild AR lesions had an ADG reduction of 6.2%, while pigs with severe AR lesions had a significant, 9.4% reduction in ADG as compared to the AR-free pigs. The extent of weight gain reduction over the whole life cycle was very similar (approximately 6%) in the pigs having either AR or pneumonia alone. In those pigs where both respiratory diseases were present, their effects seemed to be added up (11.5%); however, nasal lesion scores and percentage of lung consolidation did not show statistically apparent interactive effects on growth performance.     

Efficacy of Bordetella bronchiseptica bacterin in controlling enzootic atrophic rhinitis in swine.

The efficacy of a Bordetella bronchiseptica bacterin was evaluated in 2 commercial swine herds affected with mild and severe enzootic atrophic rhinitis (AR). In the 1st herd study, (mild AR), the degree of clinical AR, nasal turbinate evaluation, blood serum titer to B bronchiseptica antigen, and adjusted days from birth to 100 kg were determined for individual pigs. Bacterin inoculation reduced the incidence and severity of gross turbinate atrophy 57% and reduced clinical AR over 93%. Inoculated swine had an average blood serum-agglutinating titer greater than 1:2,793 and noninoculated (control) swine had an average titer of 1:112. Increased serum titer significantly (P less than 0.05) correlated with decreased degree of nasal turbinate atrophy. Inoculated and control pigs reached 100 kg in an average of 171 and 178 days after birth, respectively. In the 2nd study (severe enzootic AR), inoculated and control pigs were individually evaluated for clinical AR and total average daily weight gain. Inoculation reduced clinical AR over 90%. The total average daily gain for the inoculated and control pits was 435.84 g and 340.50 g, respectively. Inoculated pigs and control pigs reached 100-kg market weight in 184 and 238 days, respectively.     

Pneumonic lesions in lambs in New Zealand: patterns of prevalence and effects on production

AIM: To describe temporal and spatial patterns of the prevalence of pneumonia in lambs in three regions of New Zealand, and determine effects on liveweight gain. METHODS: A longitudinal study was conducted in 1999- 2000 on 14 commercial sheep farms, five from the Southland region of the South Island, and five from the King Country and four from the Northland regions of the North Island. Pneumonia was known to be a problem in lambs on all farms selected. On each farm, 400 lambs were randomly selected at weaning and allocated at random to one of two groups (Groups I and II). Lambs in both groups were weighed at 4-weekly intervals. The extent of pneumonic lesions in lungs was scored visually at slaughter in 40 randomly selected lambs after each weighing (Group I). Lambs in Group II were selected for slaughter by the farm manager on a commercial basis of liveweight and body condition, then assessed for pneumonic lesions. RESULTS: Prevalence of extensive pneumonic lesions (>/=10% lung surface area affected) increased from December to March from 1.4 to 10.1% lambs in Southland (n=1,917), 1.2 to 25.7% in the King Country (n=1,831), and 4.7 to 21.4% in Northland (n=1,485). Overall, 42.3% of lambs in both groups had pneumonic lesions (n=5,233) and in 15.1% of these, >/=5% of the lung surface area was affected. Daily weight gain in the month prior to slaughter was reduced in lambs for which >/=20% lung surface area was affected in Group I (p<0.05) but not in Group II. CONCLUSIONS: The association between pneumonic lesions and reduced weight gain was highly significant in lambs from Group I, but not from Group II. Thus, pneumonia had a negative impact on weight gain, and selection by farmers of lambs for slaughter counteracted this association in lambs from Group II. CLINICAL RELEVANCE: Pneumonia occurs commonly as a subclinical disease in lambs in New Zealand. It has no public health significance and is not recorded at slaughter plants nor reported to farmer clients. Effects of the disease on daily weight gain of lambs is considerable and costly for lamb producers.     

Efficacy of a combination of amoxicillin and clavulanic acid in the treatment of pneumonia of pigs

Amoksiklav was used in the therapy of mixed respiratory tract infections in weaned pigs under field conditions. Positive effects of therapy with Amoxicillin and Clavulanic acid were observed in the majority of treated pigs. The production losses due to pneumonia in pigs treated with this combination were lower than among control pigs treated with Oxytetracycline, also a significantly lower ratio of death was observed among experimental weaners in comparison to the controls. Thirty days after the end of the therapy it was found that the body weight gain (b. w. g) of the experimental animals was on average 800 g higher after this period and the experimental piglets grew daily in average 20 g more than the controls. Experimental pigs were slaughtered 3 days earlier than the controls and the average weight gain at slaughter was highest by 1.1 kg in this group. Average daily b. w. g. of experimental pigs during the period from birth to slaughter was 13 g higher in comparison to the controls.     

Efficacy of an inactivated aqueous vaccine for the control of enzootic pneumonia in pigs infected with Mycoplasma hyopneumoniae

The efficacy of an inactivated aqueous vaccine against Mycoplasma hyopneumoniae was evaluated at two M hyopneumoniae-infected farrow-to-finish commercial farms (A and B) in Greece. In a prospective, randomised double-blind study, two groups on each farm received intramuscular doses of either the vaccine or the adjuvant when they were one and four weeks of age. The pigs were observed daily for clinical signs of disease; morbidity and mortality were recorded; and bodyweight was recorded at intervals. At slaughter, the lungs of the animals were examined and the chest cavities were examined for signs of pleuritis. No adverse reactions to the treatments were observed in any of the pigs. On farm A the vaccinated pigs were on average 6 kg heavier at slaughter, and on farm B they were on average 4 kg heavier; on both farms the average daily gain of the pigs was greater than that of the unvaccinated pigs. The prevalence and severity of enzootic pneumonia in the affected lungs were significantly lower in the vaccinated than in the unvaccinated pigs.     

Enzootic pneumonia: comparison of cough and lung lesions as predictors of weight gain in swine.

A prospective cohort study was undertaken in a commercial swine herd to determine the relationship between weight gain and the occurrence of enzootic pneumonia (EP). Estimates of the association between EP and weight gain were obtained from multiple linear regression models, using coughing episodes or slaughter checks as indicators of EP status. Models were estimated for pigs in 2 different age groups: roasters (n = 1084, sold at 32 to 50 kg) and market hogs (n = 1162, sold at 100 to 110 kg). The relationship between presence of lung lesions at slaughter and previous coughing episodes was also investigated. Throughout the study period, clinical evaluations were performed weekly, and coughing episodes recorded for each pig. Lungs were inspected at slaughter, and scores were expressed as the percentage of the lung with gross pneumonic lesions. Coughing and lung scores were significantly correlated, after adjusting for other covariates (R = 0.32 and 0.59, respectively, for market hogs and roasters). However, the agreement beyond chance between coughing history and lung lesions at slaughter was poor among both roasters and market hogs (kappa = 0.17 and 0.07, respectively). Although very specific, weekly assessment of coughing was not a sensitive indicator of lung lesions at slaughter. In multiple regression, lung score was a highly significant predictor of lower final weight in pigs of both age groups (P < 0.001 in the selected regression models).(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of methods for assessing the prevalence and extent of pneumonia in market weight Swine

The purpose of this study was to compare four different techniques that may be used to assess the prevalence or severity of enzootic pneumonia in a swine herd. These techniques included: 1) assessing the percentage of lung involved and calculating a mean percentage and standard deviation for each herd, 2) counting the number of lungs in the herd sample that have greater than a predetermined amount of pneumonia and calculating the prevalence of the sample thus affected, 3) scoring only the lung from each herd sample that was maximally affected by pneumonia, and 4) allocating lungs to categories depending on the approximate extent of pneumonia. Five hundred and sixty pigs from 41 different swine herds in southern Minnesota were examined at slaughter and lungs were evaluated for the extent of pneumonia that was macroscopically visible.     

Effect of vaccinating lambs against pneumonic pasteurellosis under New Zealand field conditions on their weight gain and pneumonic lung lesions at slaughter

In a field trial, 9174 lambs from seven commercial sheep flocks with a history of subclinical pneumonia were either vaccinated with Ovipast Plus (Intervet) or given a placebo by systematic random allocation; they were vaccinated twice at an interval of four to six weeks and grazed on pasture in the same paddocks. They were weighed at the first vaccination, 11 and 23 weeks later, and one to three days before they were slaughtered. The extent of the pneumonic lesions in their lungs was scored visually postmortem. A subset of pneumonic lung samples was examined bacteriologically and histopathologically. There were no statistically significant differences between the pneumonic lesions at slaughter or the mean average daily weight gains of the vaccinated and placebo-treated lambs between 11 and 23 weeks or between first vaccination and slaughter. The vaccinated lambs had a lower mean daily gain between first vaccination and 11 weeks. The extent of pneumonic lesions at slaughter was negatively correlated with the mean daily gain between first vaccination and slaughter. There were no significant differences between the frequency of isolation of Mannheimia (Pasteurella) haemolytica and Pasteurella trehalosi or the histopathological classification of disease between pneumonic lung samples from the placebo-treated and vaccinated lambs.     

An Epidemiologic and Economic Study of Respiratory Diseases in Two Conventional Danish Swine Herds. I: Prevalence of Respiratory Lesions at Slaughter and Their Effects on Growth

A total of 578 slaughter pigs from 2 Danish conventional farrow-to-finish operations (Herds A and B) were followed from an age of 14 days to slaughter. Pigs were weighed at 3 weeks intervals and at slaughter and an extended post mortem examination of the plucks was done. Comparison of growth rates in pigs with and without specific types of lesions by the t-test and those with multiple lesions with regression models demonstrated that Mycoplasma-like pneumonia, complicated pneumonia, anterio-ventral pleuritis, fissures and atrophic rhinitis significantly reduced mean daily gain and increased the time required to reach slaughter weight. The total impact of the lesions in Herd A was an estimated reduction in mean daily gain of 27 grams and a 2 day increase in the interval from 14 days of age until slaughter (MDG14). Decreases in MDG14 in Herd B were more substantial, 98 grams and 16.7 days. Reductions in mean daily gains during the interval from the fourth weighing until slaughter were 31 grams in Herd A and 137 grams in Herd B. Chronic dorso-caudal and parietal pleuritis, without other lesions present, had no significant adverse effects on growth rates in either herd. Interactions between lesions did not significantly alter the estimates. The R² values obtained for the regression models showed that the presence, absence or extent of lesions at slaughter explained only 13-27% of the variations in growth rates in the 2 herds.     

Long-term effects of meloxicam in the treatment of respiratory disease in fattening cattle

The long-term effects of a single dose of meloxicam (Metacam 20 mg/ml; Boehringer Ingelheim Vetmedica) in conjunction with antibiotic therapy in cattle with clinical signs of bovine respiratory disease (BRD) was evaluated in a blind, controlled, randomised study. Two hundred animals with clinical signs of brd received a single subcutaneous injection of 20 mg/kg oxytetracycline; 100 of them also received a subcutaneous injection of 0.5 mg/kg meloxicam, and the other 100 received an injection of isotonic saline. The animals were weighed before they were treated and seven, 35, 70 and 105 days later, and finally before they were slaughtered. The mean bodyweight of the meloxicam-treated animals was significantly higher from day 70 until slaughter, and the mean average daily weight gain until slaughter and the mean carcase weight of the animals treated with meloxicam were significantly higher. In the animals with lung lesions, significantly less lung tissue was affected in those that had been treated with meloxicam.     

Chronological study of Mycoplasma hyopneumoniae infection, seroconversion and associated lung lesions in vaccinated and non-vaccinated pigs

A field trial was conducted to study Mycoplasma hyopneumoniae (Mh) infection dynamics by nested polymerase chain reaction (nPCR) and serology in pigs of a farm affected by enzootic pneumonia (EP). Moreover, correlation of Mh detection at different respiratory tract sites with presence of EP gross and microscopic lung lesions was assessed. These parameters were studied and compared between vaccinated (two doses at 1 and 3 weeks of age versus one dose at 6 weeks of age) and non-vaccinated pigs. Animals were monitored from birth to slaughter by nPCR from nasal swabs and by serology. From 3 to 22 weeks of age, an average of three pigs per treatment and per batch were necropsied (n = 302). The remaining pigs were sent to the slaughter (n = 103). Nasal, bronchial and tonsillar swabs were taken from the necropsied/slaughtered pigs; gross and microscopic EP-suggestive lung lesions were also assessed. Single and double vaccination resulted in earlier seroconversion and higher percentage of Mh seropositive pigs compared to control group. At slaughter, double vaccinated pigs showed lower percentage of EP-compatible gross lung lesions and lower Mh prevalence at upper respiratory tract sites (nasal cavity and tonsil) than control pigs.     

The effects of slaughter age on growth and carcass traits in an intensively managed crossbred beef herd

The purpose of this study was to determine and describe the effects of slaughter age (at constant weights) on pre- and post-weaning growth rate and carcass traits of unselected steer and heifer progeny from a crossbred beef herd. The data were obtained from 340 heifers and 377 steers weaned at 305 days of age and fed a high-energy post-weaning diet. Heifers and steers were slaughtered at individual unshrunk weights of 420 and 470 kg, respectively, and divided into slaughter age classes based on 25-day intervals. There were differences (P < 0.01) between slaughter age classes for all growth traits including 305-day (weaning) weight, post-weaning daily gain, days on feed, and weight/day. Mean 305-day weight of steers in the youngest slaughter age class (347.8 kg; 376–400 days of age) was 28% greater than the mean of steers in the oldest age class (272.2 kg;>501 days of age). The youngest steer class averaged 63% more for daily gain than the oldest steer class (1.462 vs. 0.894 kg); the corresponding value for heifers was 64%. Post-weaning time in the feedlot ranged from 84.7 days for the youngest steer to 215.6 for the oldest steer class. Calculations based on mean differences between age classes in 305-day weight, daily gain and days on feed indicated that variability in weaning weight and in daily gain were of similar importance in determining slaughter age. Marbling score was greater (P < 0.01) for older steer classes, but was not different in the heifer data. Fat thickness of the oldest steer class was 25% more than the youngest steer class (1.89 vs. 1.51 cm); the corresponding percent in heifers was 30%. With the exception of differences in untrimmed rib and chuck percents in steers (P < 0.05), and rib specific gravity in heifers (P < 0.05), carcass quantity traits were essentially unaffected by slaughter age class when marbling score and fat thickness were included as continuous independent variables. None of the organoleptic traits (tenderness, juiciness and flavour) were affected by slaughter age class.     

地顶孢霉培养物对黑豚生长性能、屠宰性能和免疫器官指数的影响

为研究地顶孢霉培养物对黑豚生长性能、屠宰性能和免疫器官指数的影响,试验随机选取90只黑豚,将其分成3组(对照组、低剂量组、高剂量组),对照组、低剂量组、高剂量组分别在基础日粮中添加0、0.1%、0.2%的地顶孢霉培养物,测定生长性能、屠宰性能和免疫器官指数检测指标。结果表明:低剂量组与对照组相比,日均增重、半净堂率、脾脏指数均显著提高(P<0.05),料重比显著降低(P<0.05);高剂量组与对照组相比,日均增重、日均采食量、屠宰率、半净堂率、脾脏指数、肝脏指数以及肾脏指数均显著提高(P<0.05),料重比显著降低(P<0.05);高剂量组与低剂量组相比,日均增重、日均采食量、屠宰率以及半净堂率均显著提高(P<0.05)。说明黑豚基础日粮中添加0.1%和0.2%的地顶孢霉培养物均能改善黑豚的生长性能、屠宰性能和免疫器官指数,且0.2%添加剂量的作用效果更为显著。     

添加牛磺酸对樱桃谷肉鸭生产性能和肌肉品质影响的研究

200只1日龄樱桃谷肉鸭,随机分为5组,每组4个重复.分别在基础日粮中添加0.05%、0.10%、0.15%、0.20%牛磺酸,饲喂35 d.分析测定肉鸭的体重、日增重、饲料报酬、屠体品质、肉品品质及肌肉组织学结构.结果表明,添加0.10%牛磺酸可极显著增加35日龄活重和平均日增重,显著提高饲料报酬,降低肉鸭腹脂率,提高全净膛率和瘦肉率.减小肌纤维直径,提高系水力、肌间脂肪的含量,增加肌肉嫩度.     

复合益生菌制剂对肉牛生长性能、屠宰性能及经济效益的影响

为研究不同水平的复合益生菌制剂对肉牛生长性能、屠宰性能及经济效益的影响,试验选择体重(200±4)kg肉牛60头随机分成4组,每组15个重复,每个重复1头,1组饲喂基础日粮为对照组,试验2、3、4组分别添加2.5%、5.0%、10%复合益生菌制剂,预试验7 d,试验期为56 d。结果表明:(1)试验3、4组的平均日增重较1组比分别提高19.4%、18.1%(P<0.05),试验3、4组料重比较1组比分别降低9.6%、7.2%(P<0.05),试验2、3、4组的平均采食量均高于1组(P>0.05);(2)试验2、3、4组的胴体重、屠宰率均高于1组(P>0.05),试验3、4组的宰前活重、眼肌面积较1组比分别提高10.3%、9.0%、14.3%、13.9%(P<0.05);(3)试验2、3、4组试验肉牛的每千克增重成本均低于1组,试验3、4组每千克增重的饲料成本分别减少1.0元和0.77元。综上,不同水平复合益生菌制剂的添加可以提高肉牛的生长性能、屠宰性能及经济效益,以5.0%添加为适宜。     

Reduction of economic losses caused by mycoplasmal pneumonia of pigs by vaccination with Respisure and by Tiamutin treatment

The possibilities and economic benefits of controlling mycoplasmal pneumonia of pigs caused by Mycoplasma hyopneumoniae by immunisation with Respisure and by Tiamutin treatment were studied. The experiment was carried out in a herd comprising 1000 sows which was free of PRRS, Aujeszky's disease, swine dysentery and leptospirosis, and the prevalence of mycoplasmal pneumonia was low because the farm had recently been restocked. Groups C1 and C2 served as untreated controls, while Groups R1 and R2 received a prestarter diet containing 100 ppm Tiamutin from the time of weaning. Piglets of Group R1 were vaccinated with Respisure vaccine once on day 69, while those of Group R2 twice, on days 65 and 80. Piglets of Groups ST1 and ST2 were fed 100 ppm Tiamutin in the diet for 7 days at the time of weaning and then at 4 months of age, while pigs of Group ST2 received such treatment also in the 6th month of life. The efficacy of treatment was analysed on the basis of the number of animals that died, were emergency slaughtered or were retarded in growth in the different groups, the body weight of animals at weaning, at 94 and 148 days of age and at the time of slaughter, their daily body weight gain, the lung lesions found in animals slaughtered from the different groups, the costs of medication and vaccination, and the cost-benefit calculations of the results. The mortality and emergency slaughter rate was 2.88% and 4.62% in Groups ST2 and ST1, respectively, 4.23% and 4.62% in Groups R2 and R1, respectively, and 8.39% and 9.44% in the control groups (C2 and C1, respectively). The rate of growth retardation was 0.48% and 2.12% in Groups R1 and R2, respectively, 1.59% and 3.46% in Groups ST1 and ST2, respectively, as compared to 8.03% and 6.55% in the control groups (C1 and C2, respectively). The severity score of lung lesions was 1.82 and 1.46 in Groups R1 and R2, 2.18 and 2.93 in Groups ST1 and ST2, and 3.83 and 4.02 in the control groups C1 and C2, respectively. The mean finishing weight of pigs was 102.4-107.8 kg and 95.2-106.6 kg in the treated groups and 94.5-98.6 kg in the control groups. The classification of pigs according to the EUROP categories showed a shift to the E and U categories in the treated groups. The average feed cost per one kg of liveweight was 77.89-82.64 Forints in the treated groups and 85.66 Forints in the control groups.