Effect of organic acids in drinking water during the last 2 weeks prior to slaughter on Salmonella shedding by slaughter pigs and contamination of carcasses

In this study, we investigated the effect of adding organic acids to the drinking water of finishing pigs 2 weeks prior to slaughter on the shedding and prevalence rate of Salmonella at slaughter. Approximately 600 animals from four Belgian pig herds infected with Salmonella were included. At two herds, the study was conducted twice. Before the start of the study, overshoes were taken at the different herds. Two weeks prior to the expected slaughter date, the pigs were randomly divided into two groups (treatment and control group) each containing on average 50 animals within each herd. The treatment group received from this day onwards acidified drinking water (pH = 3.6-4.0), the control group received non-treated water (pH = 7.8-8.5). All other housing, feeding and management factors were identical in both groups. At the slaughterhouse, 10 pigs of each group (20 pigs for each group of study group 6) were randomly selected and sampled (blood, contents of ileum and rectum, mesenteric lymph nodes and carcass swabs). All samples were immediately transported to the laboratory and submitted to Salmonella isolation. Salmonella was isolated out of 11.9% (66/554) of the samples taken at the slaughterhouse, with the highest frequency found in the content of the ileum (18.7%), followed by 17.8% in the lymph nodes, 7.2% in the content of the rectum and 3.6% in the carcass swabs. The results did not reveal a significant difference between the treatment and control groups for the different slaughterhouse samples. The study documented that the investigated control strategy namely, the strategic application of organic acids during the last 2 weeks prior to slaughter was insufficient to decrease Salmonella shedding and contamination shortly before and during slaughter.     

Effect of acidified feed on the prevalence of Salmonella in market-age pigs

Two trials were carried out to determine the effect of feed acidification upon Salmonella carriage in market-age pigs. In the first trial, the administration for the last 14 weeks of the fattening period of a commercial pelleted feed added with 0.6% lactic acid plus 0.6% formic acid (Lac-Formic-1.2) was compared to an unacidified standard diet (STD). A second experiment was carried out in two herds of growing pigs (Herd I, 3000 pigs; Herd II, 900 pigs) in which three different diets were assayed during the last 8-9 weeks of the fattening period: a diet containing 0.8% formic acid (Formic-0.8), a diet containing 0.4% lactic acid plus 0.4% formic acid (Lac-Formic-0.8) and a STD. In the first experiment, serological evolution of the infection was examined by ELISA and microbiological cultures (rectal samples and mesenteric lymph nodes) were also done. Feed intake by pen and the individual weight of the animals were also measured. In the second trial, blood, rectal samples and mesenteric lymph nodes were collected at slaughter in both herds (30 pigs per experimental group). In the first experiment, the acidified diet (Lac-Formic-1.2) reduced Salmonella carriers in mesenteric lymph nodes (Fisher's exact P < 0.01). In the second trial, Lac-Formic-0.8 diet significantly reduced Salmonella seroprevalence compared to the STD (P = 0.001) in both herds. Also Lac-Formic-0.8 and Formic-0.8 diets in Herd II showed a lower faecal excretion and Salmonella carriage in mesenteric lymph nodes than the STD (P < 0.05). Our results suggest that the administration of a combination of lactic and formic acids at the levels used in this study could be used to reduce Salmonella prevalence in finishing pigs.     

自配料与商品料对生长猪育肥效果比较

选用 12头平均体重 36 6± 0 9kg(P >0 0 5 )、日龄相近、健康的大约×清平二元杂交生长猪 ,随机分为Ⅰ、Ⅱ、Ⅲ组处理 ,分别饲喂自配料 +自配添加剂、自配料、商品料进行试验 ,试验期为 4 0d。结果显示 :(1)Ⅰ、Ⅱ、Ⅲ组处理的料肉比分别为 3 5 3、3 5 7、3 80 ,Ⅰ组比Ⅲ组料肉比下降 7 1% ,Ⅱ组比Ⅲ组下降 6 1% ;饲料成本下降 18 8%。 3组间的平均日增重无显著差异 (P >0 0 5 )。 (2 )增重营养成本 ,DE :Ⅰ组比Ⅲ组下降 5 0 % ,Ⅱ组比Ⅲ组下降 4 0 % ;CP :Ⅰ组比Ⅲ组下降 5 0 % ,Ⅱ组比Ⅲ组下降 3 6 %。     

非常规饲料原料对生长育肥猪屠宰性能和肉品质的影响

文章旨在评估日粮添加非常规饲料原料对生长育肥猪屠宰性能和肉品质的影响。试验将12周龄平均初始体重为(33.15±1.23)kg的450头(公母各半)生长猪随机分为3组,每组5个重复,每个重复30头猪。对照组饲喂常规玉米-豆粕-小麦型日粮,处理1组饲喂含有30%马铃薯茎叶和10%苜蓿草的日粮,处理2组饲喂含有30%马铃薯茎叶、10%苜蓿草及0.5%中草药提取物的日粮,试验共开展10周。结果:处理1和2组较对照组显著提高生长猪屠宰率和背膘厚度(P<0.05),但瘦肉率和眼肌面积显著降低(P<0.05)。日粮处理与性别对屠宰率、胴体长度、眼肌面积及背膘厚度的影响具有显著交互作用(P<0.05)。处理组较对照组显著提高了肌肉系水力(P<0.05),处理2组肌肉的适口性显著高于对照组(P<0.05)。此外,处理组肌肉粗蛋白质含量显著高于对照组(P<0.05),而脂肪含量显著降低(P<0.05)。结论:与常规饲料相比,非常规饲料对生长育肥猪肌肉感官特性表现出积极影响,特别是改善了适口性和嫩度。     

饲料中添加发酵豆粕对育肥猪生长性能、屠宰性能及经济效益的影响

为研究饲粮中添加发酵豆粕对育肥猪生长性能、屠宰性能及经济效益的影响,试验选择体重相近、健康的三元杂交育肥猪80头随机分成4组,每组20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组分别用发酵豆粕替代基础日粮中50％、75％、100％的豆粕,预试验7 d,试验期56 d.结果表明:(1)试验3、4组的平...     

亚麻籽对育肥牛肉品质及脂肪酸的影响

本试验旨在研究亚麻籽对育肥牛肉品质及脂肪酸的影响。选择体重接近的西门塔尔杂交牛32头,采用单因素试验设计,随机分为4组,每组8头,其中试验Ⅰ组(对照组)、Ⅱ组、Ⅲ组和Ⅳ组牛饲喂亚麻籽的比例分别占精料0%,5%,10%和15%。结果表明,1)各试验组屠宰率,净肉率与对照组比较无显著差异(P>0.05),背膘厚度显著提高(P＜0.05),试验Ⅳ组的背膘厚度比对照组显著提高了57.75%,牛肉中脂肪含量显著提高(P＜0.05); 2)日粮中添加亚麻籽显著降低育肥牛宰后24和48 h剪切力(P＜0.01)和pH(P＜0.01);3)日粮中添加亚麻籽使肉牛背最长肌中多不饱和脂肪酸(PUFA)显著提高(P＜0.01)。日粮中添加亚麻籽可以改善胴体品质,优化了肉牛肌肉的脂肪酸组成,特别是显著增加了PUFA含量。综合分析,亚麻籽在育肥牛日粮中的适宜饲喂比例为精料的10%～15%。     

中草药添加剂对育肥猪生长性能及血液生化指标的影响

将120头胎次、日龄相近,体质量在70kg左右的＂杜×长×大＂三元杂交猪随机分为4组,空白对照组只饲喂基础饲粮,西药组添加0.02%半胱胺,其他2组分别添加1%和0.5%的中草药添加剂。结果表明：在生长性能方面,2个中药组（B、C组）、半胱胺组（D组）的日增重分别比空白对照组（A组）提高了9.89%（P〈0.05）,4.42%（P〉0.05）和1.26%（P〉0.05）,料肉比分别比对照组降低了7.07%（P〈0.05）,4.49%（P〈0.05）和3.97%（P〈0.05）;添加中草药添加剂,对猪只肝肾功能无不良影响。     

The effect of fermented persimmon shell diet supplementation on the growth performance and blood parameters in finishing pigs

The objective of the present study was to investigate the effects of fermented persimmon shell diet (FPSD) supplementation on growth performance and blood parameters in 96 Berkshire pigs. The FPSD was made from persimmon shell and mixed with rice bran and barley bran. Samples of FPSD on day 0 (D0) and day 60 (D60) were analyzed for chemical composition, pH and organic acids. The experimental diets were 0, 3, 5 and 7% FPSD added to C, T1, T2 and T3 of finishing diets on fresh matter basis. Dry matter (DM) was lower (P < 0.01) and crude protein was higher (P < 0.01) on D60 than on D0. pH value decreased (P < 0.01) on D60 than on D0 but organic acids were increased (P < 0.01). Average daily gain was higher (P < 0.05) in T2 than in other groups. Average daily feed intake was higher (P < 0.05) in T2 than in other groups. Total cholesterol was higher (P < 0.05) in T3 than in other groups. High‐density lipoprotein cholesterol increased (P < 0.05) in groups by the addition of FPSD. Blood urea nitrogen was lower (P < 0.05) in C than in other groups. The results indicate that FPSD improved the growth performance and blood parameters in Berkshire pigs.     

Effect of an organic acid blend and phytase added to a rapeseed cake‐containing diet on performance,intestinal morphology,caecal microflora activity and thyroid status of broiler chickens

The experiment was carried out on 96 female broilers, allocated to eight groups of 12 birds kept in individual cages. Two basal wheat‐ and soyabean meal‐based diets containing 150 g/kg of rapeseed expeller cake were formulated, differing in the level of P: 7.1 g/kg in diet H or 5.9 g/kg in diet L. Rapeseed cake supplied 3.15 μmol alkenyl glucosinolates per gram of diet. The eight treatments were: basal diets only, basal diets + phytase (1000 U/kg), basal diets + organic acid blend (OA, 6 g/kg), or basal diets + both additives. Diets were fed from day 8 to 28 of life. The results showed that the lower dietary P content and OA supplementation did not significantly affect feed intake or BWG, while both increased (p < 0.001) after phytase supplementation. Tibia ash content as well as tibia ultimate strength were lower (p < 0.001) in birds fed diets L compared with diets H, and increased (p < 0.01) with phytase supplementation of diet L, while OA had no influence on either parameter. Dietary P levels and OA supplementation had no influence on the pH of gut digesta, but the pH of jejunal digesta increased following phytase supplementation (p < 0.01). Morphological measurements of the small intestinal mucosa of chicks indicated that OA added to diet L depressed villi height (p < 0.001) and crypt depth (p < 0.001); both parameters increased after phytase supplementation (p < 0.01). The lower total SCFA as well as acetic, propionic and butyric acid concentrations in caecal digesta indicated lower activity of caecal microflora in birds fed diets L compared with H. OA supplementation had no influence, while phytase supplementation increased the concentration of acetic acid in caecal digesta. Supplementation of diets with either phytase or OA increased thyroid weight by 16% (p < 0.01) and 11% (p < 0.05) respectively. The increase in thyroid weight because of phytase supplementation was greater at the lower dietary P level, and the greatest when both phytase and OA were added to the diet.     

Effects of slaughter age on the levels of free amino acids and dipeptides in fattening cattle

The effects of slaughter age, breed type and postmortem period were studied on the concentrations of free amino acids (FAA) and dipeptides (carnosine and anserine) in Longissimus dorsi muscle of beef. Slaughter age affected the levels of most FAA and dipeptides, and the concentrations of these compounds were significantly lower at 35 months of age than either 15 or 25 months of age. Slight increases were observed at 25 months compared with 15 months, but the differences were not significant except for a few FAA. These tendencies still remained when the concentrations were recalculated on the basis of protein. A significant breed effect was observed for taurine, carnosine and anserine. Almost all FAA were significantly increased during postmortem conditioning, but the level of each FAA fluctuated, and the fluctuations could not be explained statistically by slaughter age or breed differences.     

Effects of ensiling cereal grains (barley,wheat, triticale and rye) on total and pre‐caecal digestibility of proximate nutrients and amino acids in pigs

Inclemency of weather frequently causes critical water contents in cereal grains above 15%. Ensiling in pre‐mature condition may be an alternative to other techniques of preservation. Aim of this study was to compare apparent total tract digestibility (D_t; barley, wheat, triticale, rye) of proximate nutrients and pre‐caecal digestibility (D_pc; barley, wheat) of amino acids (AA), respectively, from cereal grains in ensiled and almost dry condition. Moistly harvested cereal grains (67–73% dry matter) were milled through a 4‐mm sieve and ensiled with lactic acid bacteria (LAB, 3 × 10⁵ colony forming units/g Lactobacillus plantarum DSMZ 8862 and 8866). To investigate D_t, two trials were conducted with six Mini‐Lewe pigs and four German Landrace pigs, respectively. D_pc of AA was determined using four German Landrace pigs with ileo‐rectal anastomosis. D_t of proximate nutrients did not differ between cereal grains and their silages, except for ether extract, which was more digestible in ensiled than dry wheat, triticale and rye (p < 0.05). Lysine content was lower in ensiled than dry barley and wheat. In barley, ensiling was accompanied by reduced D_pc of lysine and histidine (p < 0.05). In wheat, ensiling increased D_pc of lysine, methionine, threonine and leucin (p < 0.05). Ensiling of pre‐mature cereal grains with LAB can serve as a reasonable storage alternative. However, as limited data are yet available, further research is required to understand completely the impact of ensiling on nutritional value as indicated, for example, by the lysine content and the D_pc of certain AA.     

Effect of feed intake level and dietary protein content on the body temperature of pigs housed under thermo neutral conditions

Feed intake and diet composition appear to affect the body temperature of pigs. Two trials were conducted to analyse the effect of feed intake level and dietary protein content on the intestinal temperature (IT) of pigs housed under thermo neutral conditions. Ten pigs (64.1 ± 1.3 kg initial body weight) fitted with an ileal cannula were used. A thermometer set to register the IT at 5‐min intervals was implanted into the ileum through the cannula. In both trials, the ambient temperature ranged from 19.1 to 21.6°C and the pigs were fed at 07:00 and 19:00 hr (same amount each time). In trial 1, the pigs were fed daily 1.2 or 1.8 kg of a wheat–soybean meal diet. The IT followed a similar pattern along a 24‐hr period regardless the feed intake level. The IT rapidly increased up to 0.61 and 0.74°C after the morning meal and up to 0.53 and 0.47°C after the evening meal in pigs fed 1.2 and 1.8 kg/d respectively. The postprandial IT was higher in pigs fed 1.8 kg after each meal (p < .05). In trial 2, pigs were fed daily 1.8 kg of a low (11%) or a high (22%) crude protein diet. The IT followed a similar pattern along the 24‐hr period regardless the dietary protein level. The postprandial IT did not differ between pigs fed the low protein or the high protein (p > .10). The IT rapidly increased up to 0.66 and 0.62°C after the morning meal in pigs fed the high‐ and low‐protein diet (p < .05), but there was no change after the evening meal (p > .10). In conclusion, the feed intake level affected the IT of pigs housed under TN conditions, but the dietary protein content had no effect.     

Effects of dietary addition of Macleaya cordata alkaloid extract on growth performance,caecal indices and breast meat fatty acids profile in male broilers

The aim of this experiment was to investigate whether a low‐dietary application (15 mg/kg) of an alkaloid preparation containing quaternary benzo[c]phenanthridine alkaloids and obtained from Macleaya cordata (Sangrovit) influenced caecal metabolism, growth performance and long‐chain fatty acid composition of breast meat. One‐day‐old broiler chicks (Cobb 500) were fed a diet without supplement or with a 15 mg/kg dose of Sangrovit (C and A groups respectively) for 5 weeks. Although the A treatment was not accompanied by an enhanced final body weight of broilers, the intake of a diet with Sangrovit influenced the caecal microflora activity. The addition of Sangrovit to a diet decreased potentially harmful β‐glucuronidase and β‐glucosidase activities (p < 0.05 and p = 0.075 respectively), and at the same time led to a significant increase in activities of bacterial glycolytic enzymes α‐glucosidase, α‐galactosidase, β‐galactosidase in comparison to the control group. The concentration of total short‐chain fatty acids in the caecal digesta was increased in the A treatment contributing to the tendency towards lower caecal pH (p = 0.078). The analysis of breast meat fatty acids showed that the dietary application of Sangrovit evoked some changes in contents of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) contents. The applied dosage of Sangrovit caused an increase in the sum of MUFA and the tendency towards lower PUFA sum (p < 0.05 and p = 0.062 respectively) as in relation with the C group. Although the nutritionally relevant n‐6/n‐3 PUFA and the (PUFA + MUFA)/saturated fatty acids ratios remained similar in both groups, further research is postulated to establish the effect of this preparation on meat quality. To sum up, despite of a lack of the improvement in final body weight, a low dose of dietary Sangrovit was found to exert positive effects on the caecal metabolism of the broilers.     

Effects of wood kraft pulp feeding on feed digestibility and rumen fermentation of Japanese Black steer in the middle fattening stage

We investigated the effects of wood kraft pulp (KP) feeding on feed digestibility and rumen fermentation of Japanese Black (JB) steer in the middle fattening stage. The feeding experiment was carried out a replicated 3 × 3 Latin square design using six JB steers (16.2 ± 0.8 months of age). Steers were fed rice straw and three concentrated feeds: commercial formula feed (control), formula feed containing 7.5% KP on a dry matter (DM) basis (7.5% KP), and formula feed containing 15% KP on a DM basis (15% KP). Feed digestibility and rumen fermentation parameters were recorded for 3 days during the measurement period, after an adaptation phase of 11 days. There was no significant difference in DM intake per day among diets. A slightly higher digestibility of neutral detergent fiber was observed in steers fed 15% KP, compared with those fed other diets (P = 0.059). The butyric acid ratio in rumen fluid was higher in steers fed KP diets than in steers fed control (P = 0.083). The average ruminal pH was unaffected by KP diets. This study suggests that replacing 15% of concentrated feed with KP has little effect on feed digestibility and rumen fermentation in JB fattening steer.     

The capacity of inspection on farm and at the abattoir to predict post-mortem outcomes in slaughter pigs: A study at animal level

The aim of this study was to investigate associations between ear, tail, and skin lesions, hernias, bursitis, and rectal prolapses at the abattoir and meat inspection outcomes in slaughter pigs, including carcass condemnations and trimmings, carcass weight, and carcass quality. This was an observational study whereby pigs were managed according to routine practices in a single abattoir. Data were collected from 1816 pigs. The relationship between animal-based welfare and post-mortem outcomes was analyzed using generalized mixed models (Proc Glimmix). Our findings showed that tail lesions were associated with entire carcass condemnations and trimmings (P < 0.001), a reduction in carcass weight (P < 0.05), and a potential to impair carcass quality by reducing muscle pH (P < 0.05), especially in carcasses from male pigs (P < 0.05). Additionally, hernias were associated with viscera condemnation (P < 0.05) and a reduction in carcass weight (P  < 0.05). Therefore, our findings confirm that ante-mortem inspection could be useful to predict post-mortem outcomes in the same pigs, especially in cases of tail lesions and hernia, which might trigger attention of the veterinary inspector in charge of the post-mortem inspection.     

Effects of dietary additives (potassium diformate/organic acids) as well as influences of grinding intensity (coarse/fine) of diets for weaned piglets experimentally infected with Salmonella Derby or Escherichia coli

The aim of this study was to examine whether and to what extent the addition of potassium diformate (pdf) or free organic acids (fpa) to the diet and the grinding intensity might affect the course of infection and the passage of orally applied Salmonella and Escherichia coli in pigs. Experiments were carried out using 80 reared piglets allotted to four groups. Pigs were fed pelleted diets ad libitum (except during a 15 h feed‐withholding‐period before infection). The control diet contained finely ground cereals (2 mm screen). To two test diets (also finely ground) 1.2% pdf, 0.9% organic acids (75% formic and 25% propionic acid, fpa) respectively were added. The fourth diet (without acids) was based on coarsely ground cereals (6‐mm screen). After experimental infection alternately with S. Derby or E. coli, the course of infection was examined (rectal swab technique). Pigs were sacrificed 4–5 h after a further oral application of ～10⁹–10¹⁰ CFU S. Derby or E. coli to determine the counts of Salmonella or E. coli in chyme (classical culture methods). Adding pdf or fpa to the diet led to reduced Salmonella shedding and resulted in significantly lower counts of Salmonella and E. coli in the stomach content indicating an improved efficacy of the stomach barrier. In the distal parts of the digestive tract, the effect was less obvious concerning counts of E. coli, whereas counts of Salmonella were reduced markedly as well. The diet based on coarsely ground cereals failed to demonstrate positive effects concerning infection and passage of orally applied bacteria as well, but this diet was also pelleted and showed unintentionally, comparable amounts of fine particles. Results obtained in this study allow the recommendation of using pdf or organic acids as additives when dietary measures against Salmonella or E. coli in pigs are required.     

不同能量水平日粮对深县猪生长性能、养分消化率和血液生化指标的影响

为了研究不同消化能水平日粮对深县猪生长性能、养分消化率和血液生化指标的影响,选用体重(15. 54±2. 25) kg的健康深县猪48头,随机分成3组,每组4个重复,每个重复4头猪,试验Ⅰ、Ⅱ、Ⅲ组饲粮消化能水平分别为11. 20、11. 70、12. 20 MJ/kg,预试期7 d,正式期28 d。结果显示:试验Ⅲ组的平均日增重显著高于试验Ⅰ组15. 56%(P<0. 05),试验Ⅲ组的料重比(F/G)显著低于试验Ⅰ组(P<0. 05);试验Ⅲ组粗蛋白、总能与粗脂肪表观消化率均显著高于试验Ⅰ组9. 89%、7. 29%、7. 21%(P<0. 05)。综合各项指标,在本试验条件下,生长期深县猪适宜的消化能水平为12. 20 MJ/kg。     

Effects of dietary supplementation of Chinese medicinal herbs on polymorphonuclear neutrophil immune activity and small intestinal morphology in weanling pigs

The purpose of this study was to evaluate the effects of dietary Chinese medicinal herbs (CMH) supplementation composed of Panax ginseng, Dioscoreaceae opposite, Atractylodes macrocephala, Glycyrrhiza uralensis, Ziziphus jujube and Platycodon grandiflorum, on the performance, intestinal tract morphology and immune activity in weanling pigs. Two hundred and forty weaned pigs were assigned randomly to four dietary groups including the negative control (basal diet), 0.1% CMH, 0.3% CMH and 0.114% antibiotic (Chlortetracycline calcium Complex, Sulfathiazole and Procaine Penicillin G) supplementation groups for a 28-day feeding trial. Results indicated that both CMH supplementation groups had a better gain and feed/gain than control group (CT) during the first 2 weeks of the experimental period. The 0.3% CMH had a significant decrease in the diarrhoea score in first 10 days of experimental period when compared with other groups. The CMH supplementation groups had a higher villous height, increased lactobacilli counts in digesta of ileum and decreased coliform counts in colon compared with CT. The immune activities of polymorphonuclear leucocytes (PMNs), including the respiratory burst and Salmonella-killing ability, were significantly enhanced in CMH supplementation groups at day 7 of experiment period. The CMH and antibiotic supplementations increased the nutrient digestibility such as dietary dry matter, crude protein and gross energy in weanling pigs. In conclusion, the dietary CMH supplementation improved intestinal morphology and immune activities of PMNs, thus giving rise to nutrient digestibility and reduce diarrhoea frequency in weanling pigs.     

饲料中添加不同水平的发酵豆渣对育肥猪生长性能、屠宰性能及经济效益指标的影响

为研究饲料中添加不同水平的发酵豆渣对育肥猪生长性能、屠宰性能及经济效益指标的影响,采用单因素随机设计试验,选择体重相近的健康育肥猪80头随机分成4组,每组20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组分别在基础日粮中添加5％、10％、15％发酵豆渣,预试验7 d,试验期56 d.结果表明:(1)试...