Effects of reducing dietary crude protein on growth performance, odor gas emission from manure and blood urea nitrogen and IGF-1 concentrations of serum in nursery pigs

Two experiments were conducted to investigate the effects of reducing dietary crude protein on growth performance, odor gas emission from manure and blood urea nitrogen and IGF-1 concentrations of serum in nursery pigs. In experiment 1, the dietary treatments were (i) CON (CP 19.5%) and (ii) T1 (CP 16.0%). In feces samples, NH₃, H₂S, acetic acid and butyric acid emissions during the T1 treatment were lower than during the CON treatment ( P  < 0.05). In feces-urine samples, NH₃ emission during the T1 treatment was lower than during the CON treatment ( P  < 0.05). In experiment 2, 28 crossbred (Landrace × Yorkshire × Duroc) pigs (13.58 ± 0.10 kg) were used for a 42-day growth trial. Throughout the entire experimental period, ADG and ADFI of the CON treatment were higher than the T1 treatment ( P  < 0.05). On day 14, N digestibility in pigs fed the CON diet was higher than that of pigs fed the T1 diet ( P  < 0.05). On days 28 and 42, DM digestibility of the CON diet was greater than the T1 treatment ( P  < 0.05). On dat 42, serum BUN concentration of pigs fed the CON diet was higher than that of pigs fed the T1 diet ( P  < 0.05). In conclusion, these results indicate that reduction in dietary CP concentration decreased NH₃, H₂S and VFA emissions in feces and growth performance in nursery pigs.     

The effects of pharmacological levels of zinc,diet acidification,and dietary crude protein on growth performance in nursery pigs

This experiment was conducted to evaluate potential replacements for pharmacological levels of Zn (provided by Zn oxide), such as diet acidification (sodium diformate) and low dietary crude protein (CP: 21 vs 18%) on nursery pig performance and fecal dry matter (DM). A total of 360 weaned pigs (Line 200 × 400, DNA, Columbus, NE; initially 5.90 ± 0.014 kg) were used in a 42-d growth study. Pigs were weaned at approximately 21 d of age and randomly assigned to pens (five pigs per pen). Pens were then allotted to one of eight dietary treatments with nine pens per treatment. Experimental diets were fed in two phases: phase 1 from weaning to day 7 and phase 2 from days 7 to 21, with all pigs fed the same common diet from days 21 to 42. The eight treatment diets were arranged as a 2 × 2 × 2 factorial with main effects of Zn (110 mg/kg from days 0 to 21 or 3,000 mg/kg from days 0 to 7, and 2,000 mg/kg from days 7 to 21), diet acidification, (without or with 1.2% sodium diformate), and dietary CP (21% or 18%, 1.40% and 1.35% in phases 1 and 2 vs. 1.20% standardized ileal digestible Lys, respectively). Fecal samples were collected weekly from the same three pigs per pen to determine DM content. No 2- or 3-way interactions (P > 0.05) were observed throughout the 42-d study for growth performance; however, there was a Zn × acidifier × CP interaction (P < 0.05) for fecal DM on day 7 and for the overall average of the six collection periods. Reducing CP without acidification or pharmacological levels of Zn increased fecal DM, but CP had little effect when ZnO was present in the diet. From days 0 to 21, significant (P < 0.05) main effects were observed where average daily gain (ADG) and gain:feed (G:F) increased for pigs fed pharmacological levels of Zn, sodium diformate, or 21% CP (P < 0.065). In the subsequent period (days 21 to 42) after the experimental diets were fed, there was no evidence of difference in growth performance among treatments. Overall (days 0 to 42), main effect tendencies were observed (P < 0.066) for pigs fed added Zn or sodium diformate from days 0 to 21, whereas pigs fed 21% CP had greater G:F than those fed 18% CP. Pig weight on day 42 was increased by adding Zn (P < 0.05) or acidifier (P < 0.06) but not CP. In summary, none of the feed additives had a major influence on fecal DM, but dietary addition of pharmacological levels of Zn or sodium diformate independently improved nursery pig performance.     

Effects of two dietary crude protein levels on finishing performance,meat quality,and gene expression of market lambs

Seventeen crossbred lambs were assigned randomly to low-protein (LP; 8% crude protein [CP]; n = 9) and high-protein (HP; 13% CP; n = 8) diets for 9 weeks. The final body weight, average daily feed intake (ADFI), and average daily gain (ADG) of the HP lambs were significantly higher (P < 0.05) than the LP lambs; however, gain to feed ratio (G:F) for the LP lambs was significantly higher (P < 0.05) than the HP lambs. Hot carcass weight (HCW), adjusted fat thickness, and drip loss of longissimus dorsi (LD) muscle were significantly higher (P < 0.05) for the HP than LP lambs. In contrast, instrumental color values L*, a*, b*, C*, and hue angle (H) of meat from the LP lambs scored significantly higher (P < 0.05) than the HP lambs. The LD muscle from HP lambs had significantly greater CLA of cis-9 trans-11 isomer (P < 0.05) than the LP lambs. The gene expression of metabolism and meat quality-related genes of LP was significantly higher than HP (P < 0.05). These results suggest that a higher dietary CP level promotes growth performance for finishing lambs, whereas lower dietary CP level is beneficial for meat quality, especially when evaluating color characteristics in the final product.     

Effects of dietary supplementation of modified zinc oxide on growth performance,nutrient digestibility,blood profiles,fecal microbial shedding and fecal score in weanling pigs

One hundred and forty piglets ((Landrace × Yorkshire) × Duroc, 21 day of age) with an initial weight of 6.50 ± 0.71 kg, were randomly allotted into four treatments to determine the effects of a modified form of zinc oxide (ZnO) on growth performance, nutrient digestibility, blood profiles, fecal microbial shedding and fecal score in weanling pigs. Dietary treatments were: (i) NC, negative control, basal diet containing zinc (Zn) from the premix; (ii) PC, positive control, basal diet containing Zn‐free premix + 3000 ppm ZnO; (iii) H1, basal diet containing Zn‐free premix + 3000 ppm ZnO (phase 1, days 1 to 14)/200 ppm modified ZnO (phase 2, days 15 to 42); (iv) H2, basal diet containing Zn‐free premix + 300 ppm modified ZnO (phase 1)/200 ppm modified ZnO (phase 2). During days 1 to 14, average daily gains (ADG) were higher (P = 0.04) in PC, H1 and H2 groups than that in NC group. Overall, H1 treatment increased the ADG compared with NC (P = 0.05). On day 14, the alkaline phosphatase and plasma Zn concentration were increased (P = 0.01 and 0.04, respectively) in PC, H1 and H2 treatments compared with NC treatment. On days 14 and 42, the fecal Lactobacillus counts in NC group were lowest (P = 0.01, P = 0.04 respectively) among treatments. All supplemented groups showed lower (P = 0.03) fecal score than NC treatment on days 21 and 28. In conclusion, dietary supplementation with modified ZnO increased growth rates and reduced fecal scores in weanling pig. Modified ZnO could be used as a substitute to ZnO as a growth promoter and reduce Zn excretion to the environment because of the lower dosage. [Correction added on 3 February 2015, after first online publication: the initial weight of ‘6.50 ± 1.11 kg’ has been replaced with ‘6.50 ± 0.71 kg’ in the abstract.]     

Functional amino acid supplementation,regardless of dietary protein content,improves growth performance and immune status of weaned pigs challenged with Salmonella Typhimurium

High dietary protein may increase susceptibility of weaned pigs to enteric pathogens. Dietary supplementation with functional amino acids (FAA) may improve growth performance of pigs during disease challenge. The objective of this study was to evaluate the interactive effects of dietary protein content and FAA supplementation above requirements for growth on performance and immune response of weaned pigs challenged with Salmonella. Sixty-four mixed-sex weanling pigs (13.9 ± 0.82 kg) were randomly assigned to dietary treatments in a 2 × 2 factorial arrangement with low (LP) or high protein (HP) content and basal (AA–) or FAA profile (AA+; Thr, Met, and Trp at 120% of requirements) as factors. After a 7-d adaptation period, pigs were inoculated with either a sterile saline solution (CT) or saline solution containing Salmonella Typhimurium (ST; 3.3 × 10⁹ CFU/mL). Growth performance, body temperature, fecal score, acute-phase proteins, oxidant/antioxidant balance, ST shedding score in feces and intestinal colonization, fecal and digesta myeloperoxidase (MPO), and plasma urea nitrogen (PUN) were measured pre- and postinoculation. There were no dietary effects on any measures pre-inoculation or post-CT inoculation (P > 0.05). Inoculation with ST increased body temperature and fecal score (P < 0.05), serum haptoglobin, plasma superoxide dismutase (SOD), malondialdehyde (MDA), PUN, and fecal MPO, and decreased serum albumin and plasma reduced glutathione (GSH):oxidized glutathione (GSSG) compared with CT pigs (P < 0.05). ST-inoculation reduced average daily gain (ADG) and feed intake (ADFI) vs. CT pigs (P < 0.05) but was increased by AA+ vs. AA– in ST pigs (P < 0.05). Serum albumin and GSH:GSSG were increased while haptoglobin and SOD were decreased in ST-inoculated pigs fed AA+ vs. AA– (P < 0.05). PUN was higher in HP vs. LP-fed pigs postinoculation (P < 0.05). Fecal ST score was increased in ST-inoculated pigs on days 1 and 2 postinoculation and declined by day 6 (P < 0.05) in all pigs while the overall score was reduced in AA+ vs. AA– pigs (P < 0.05). Cecal digesta ST score was higher in HP vs. LP-fed pigs and were lower in AA+ compared with AA– fed pigs in the colon (P < 0.05). Fecal and digesta MPO were reduced in ST pigs fed AA+ vs. AA– (P < 0.05). These results demonstrate a positive effect of FAA supplementation, with minimal effects of dietary protein, on performance and immune status in weaned pigs challenged with Salmonella.     

Effect of protein level on performance,nitrogen utilisation and carcass composition in finisher pigs

Abstract

For 6 weeks, 256 female finisher pigs (initially 53.9 kg) were fed four dietary treatments of 136, 148, 159 and 168 g crude protein (CP)/kg diet. The latter diet was the 159 g CP/kg diet supplemented with dispensable amino acids, to study the effect of excess CP. Week 4 included use of metabolic cages. Feed intake, gain and feed utilisation were not significantly affected. Plasma urea (P < 0.001) and urinary nitrogen (P = 0.01) decreased linearly by lowering CP. The weight of the carcass tended to increase linearly by reducing CP, but neither nitrogen retention nor carcass meat percentage and back fat depth differed among treatments. In conclusion, the study indicated that CP could be decreased to 136 g/kg as-fed for growing pigs in the weight range 50–100 kg without negative impact on growth performance and carcass traits. Moreover, leanness was not affected by excess CP.     

Effects of different levels of dietary protein with or without plant extract YGF251 on growth performance,nutrient digestibility,blood profiles,fecal microbial shedding,and fecal gas emission in growing pigs

This experiment was conducted to evaluate the effects of plant extract YGF251 supplementation in different protein level diets on growth performance, nutrient digestibility, blood profiles, fecal microbial shedding, and fecal gas emission in growing pigs. A total of 144 pigs (24.72 ± 1.54 kg) were randomly assigned to the treatments in a 2 × 3 factorial arrangement of dietary protein levels (15.50%, 14.00% or 12.50%) and plant extract YGF251 levels (0 or 0.05%) with 6 replications per treatment and 4 pigs per pen. Pigs fed low protein diets had reduced average daily gain (p < 0.05) and increased feed conversion ratio (p < 0.01) compared with pigs fed high protein diets. The apparent total tract digestibility of nitrogen was decreased (p < 0.05) when reducing dietary protein level. Fecal ammonia and hydrogen sulfide emissions were reduced (p < 0.05) when reducing dietary protein level. In conclusion, the results of the current study indicated that reducing dietary protein level impaired growth performance and nitrogen digestibility but reduced ammonia and hydrogen sulfide emissions in growing pigs. Dietary supplementation with 0.05% herbal extract YGF251 was not effective in improving growth performance, nutrient digestibility, or in decreasing gas emission in different protein diets.     

日粮粗纤维水平对鹅生产性能、代谢激素和生化指标的影响

以500只29日龄生长鹅为试验动物,以砻糠和玉米秸秆为主要纤维源,进行28 d的饲养试验,研究日粮在等能量等蛋白水平下,不同粗纤维(crude fiber,CF)水平(3%、5%、7%、9%和11%)对鹅生产性能、代谢激素和血清生化指标的影响。结果表明:随着日粮粗纤维水平的增加,生长鹅的日采食量呈增加的趋势,但各处理组间差异不显著(P>0.05),饲料转化率和日增重呈先增加后减少的趋势(P<0.05);5?组与7?组生长鹅的生产性能最佳,与11?组相比,日增重分别提高了22.60%与24.25%(P<0.05),饲料转化率分别改善了22.65%与21.74%(P<0.05);日粮粗纤维水平对生长鹅血清中血糖(GLU)、碱性磷酸酶(ALP)、生长激素(GH)和IGF-I有显著影响(P<0.05),而对尿酸(UA)、总蛋白(TP)、谷丙转氨酶(ALT)、谷草转氨酶(AST)、胰高血糖素(GLU)、胰岛素(INS)、促甲状腺素(TSH)、三碘甲状腺原氨酸(T3)和甲状腺素(T4)均无显著影响(P>0.05)。     

Effect of dietary supplemental medium chain fatty acids instead of antibiotics on the growth performance,digestibility and blood profiles in growing pigs

Antibiotics have great functions in farm animal. However, the harm of antibiotics can't be ignored. The effects of medium‐chain fatty acids (MCFAs) supplementation to basal diet instead of antibiotics (CSP, Chlortetracycline, sulphonamide dimethazine and procaine penicillin, 1:1:1) on growth performance, nutrient digestibility and blood profile in growing pigs were studied. A total of 140 growing pigs (Landrace × Yorkshire × Duroc) with an average body weight of 27.84 ± 0.42 kg were allotted to four treatments of seven replicates/treatment and five pigs/replicate. The four experimental diets included: CON (basal diet, non‐antibiotic, negative control); CSP (CON + CSP 0.1%, positive control); M1 (CON + MCFA 0.15%) and M2 (CON + MCFA 0.3%). After 5 weeks, the fresh faecal and blood samples were collected from rectum and jugular vein respectively. The average daily gain (ADG) was significantly improved for pigs fed 0.3% MCFAs in relation to basal diet. Meanwhile, CSP supplementation had comparable effect on ADG. The lymphocyte percentage and IgG concentration were higher in blood of pigs‐fed MCFAs in relation to that of CON and CSP treatment while white blood cell and red blood cell were not affected. In relation to basal diet and CSP treatment, the digestibility of dry matter, nitrogen and gross energy (E) were unaffected with MCFAs supplementation. In conclusion, MCFAs improved growth performance on body weight gain and immune profile. Addition 0.3% MCFAs into the diet indicated that its partial positive effect as an alternative to antibiotic.     

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。     

Growth performance and gut health of Escherichia coli–challenged weaned pigs fed canola meal-containing diet

An experiment was conducted to evaluate the effects of including canola meal (CM) in diets for weaning pigs challenged with a F18 strain of Escherichia coli on growth performance and gut health. A total of 36 individually housed weaned pigs (initial body weight [BW] = 6.22 kg) were randomly allotted to one of the three diets (12 pigs/diet). The three diets were corn–soybean meal (SBM)-based basal diet (control diet) and the basal diet with 0.3% zinc oxide, 0.2% chlortetracycline, and 0.2% tiamulin (antibiotic diet) or with 20% CM diet. The diets were fed in two phases: Phase 1: days 0 to 7 and Phase 2: days 7 to 20. All pigs were given an oral dose of 2 × 10⁹ CFU of F18 strain of E. coli on day 7. Fecal score was assessed daily throughout the trial. Dietary antibiotics increased (P < 0.05) overall average daily gain (ADG) and average daily feed intake (ADFI) compared by 48% and 47%, respectively. Dietary CM increased (P < 0.05) overall ADG and ADFI by 22% and 23%, respectively; but the ADG and ADFI values for CM-containing diet did not reach those for the antibiotics-containing diet. Dietary antibiotics reduced (P < 0.05) fecal score; however, dietary CM unaffected fecal score. Dietary antibiotics decreased (P < 0.05) liver weight per unit live BW by 16% at day 20, whereas dietary CM did not affect liver weight per unit live BW (29.2 vs. 28.6). Also, dietary antibiotics increased (P < 0.05) serum triiodothyronine and tetraiodothyronine levels for day 14, whereas dietary CM did not affect the serum level of these hormones. Dietary antibiotics reduced (P < 0.05) the number white blood cells and neutrophils by 38% and 43% at day 20, respectively, whereas dietary CM tended to reduce (P = 0.09) the number white blood cells by 19% at day 20. The number white blood cells for CM diet tended to be greater (P < 0.10) than that for antibiotics diet. The dietary antibiotics decreased (P < 0.05) the concentration of individual volatile fatty acids and hence of total volatile fatty acid in cecum by 61% at day 20, whereas dietary CM decreased (P < 0.05) cecal butyric acid concentration by 61% and tended to reduce (P < 0.10) total volatile fatty acid concentration by 30% at day 20. In conclusion, the dietary inclusion of 20% CM improved ADG and tended to reduce white blood cell counts. Thus, inclusion of CM in antibiotics-free corn-SBM-based diets for weaned pigs that are challenged with F18 strain of E. coli can result in their improved performance partly through a reduction of the inflammatory response.     

Effects of growth and dietary crude protein level until first insemination on milk production during first lactation in Holstein heifers

To decrease the age at first calving in Holsteins, the effects of average daily body weight gain (ADG) and crude protein (CP) level until first insemination on growth performance and milk production were examined. The MM group had a target ADG of 0.75 kg and received a diet with a CP level of 14%. The HM and HH groups had a target ADG of 1 kg; both these groups received a diet with CP levels 14% and 16%, respectively. The ADG in the HM and HH groups was 1.1 kg, whereas in the MM group it was 0.97 kg (P < 0.01). The HM and HH groups showed no differences in withers height at body weight 350 kg. The ages at first calving in MM, HM and HH groups were 23.1, 21.0 and 21.8 months, respectively. The HM and HH groups had lower milk yield at day 305 than the MM group (P < 0.01). These results suggest that growth performance until first insemination should be maintained at an ADG of 0.97 kg or less with a CP level of approximately 14%, to shorten time until first insemination and prevent the decrease of milk yield.     

乳化脂肪粉对断奶仔猪生长性能的影响

试验旨在研究乳化脂肪粉对断奶仔猪生长性能的影响。选择21日龄的断奶仔猪,按体重相近原则随机分栏成为两个对照组(基础日粮)和一个试验组:试验组在基础日粮中添加20 kg/t的乳化脂肪粉,每个处理2个重复(♀和♂各一栏),每个重复15头,试验期为10 d。研究结果表明:试验组和对照组的平均日采食量分别为0.239 kg、0.257 kg和0.240 kg;平均日增重分别为0.144 kg、0.129 kg和0.131 kg;平均料肉比分别为1.66、1.99和1.80。试验组的平均日采食量和平均料肉比均比两个对照组的低,而试验组的平均日增重比两个对照组高。研究结果表明:在本次试验中,乳化脂肪粉可以增加断奶仔猪的日增重、降低料肉比、提高饲料利用率,乳化脂肪粉对断奶仔猪的生长性能可以产生正面影响。     

Effects of dietary leucine supplementation in low crude protein diets on performance,nitrogen balance,whole‐body protein turnover,carcass characteristics and meat quality of finishing pigs

Eighteen Duroc × Landrace × Yorkshire barrows, with an average initial body weight (BW) of 75.4 ± 2.0 kg, were randomly allotted to one of three diets with six replicates per treatment for 25 days. The diets comprised a normal protein diet (NP, 14.5% crude protein), a low crude protein diet supplemented with 0.27% alanine (LP + Ala, 10.0% crude protein), or a low crude protein diet supplemented with 0.40% leucine (LP + Leu, 10.0% crude protein). The whole‐body protein synthesis rate, whole‐body protein breakdown rate and protein deposition rate in pigs fed the LP + Leu diet were similar to the NP diet (P > 0.05), and both were significantly higher than pigs fed the LP + Ala diet (P < 0.05). The Longissimus muscle area (LMA) of pigs fed the LP + Leu diet was larger than those fed the LP + Ala diet (P = 0.05). In addition, drip loss and intramuscular fat of pigs fed the LP + Ala diet were higher than that of the others (P < 0.05). In conclusion, supplementation of leucine in low protein diet could stimulate protein deposition and improve the meat quality of finishing pigs more than an alanine‐supplemented one.     

Effects of dietary iron level on growth performance,hematological status,and intestinal function in growing-finishing pigs

This study investigated the different addition levels of iron (Fe) in growing-finishing pigs and the effect of different Fe levels on growth performance, hematological status, intestinal barrier function, and intestinal digestion. A total of 1,200 barrows and gilts ([Large White × Landrace] × Duroc) with average initial body weight (BW; 27.74 ± 0.28 kg) were housed in 40 pens of 30 pigs per pen (gilts and barrows in half), blocked by BW and gender, and fed five experimental diets (eight replicate pens per diet). The five experimental diets were control diet (basal diet with no FeSO₄ supplementation), and the basal diet being supplemented with 150, 300, 450, or 600 mg/kg Fe as FeSO₄ diets. The trial lasted for 100 d and was divided into the growing phase (27 to 60 kg of BW) for the first 50 d and the finishing phase (61 to 100 kg of BW) for the last 50 d. The basal diet was formulated with an Fe-free trace mineral premix and contained 203.36 mg/kg total dietary Fe in the growing phase and 216.71 mg/kg in the finishing phase based on ingredient contributions. And at the end of the experiment, eight pigs (four barrows and four gilts) were randomly selected from each treatment (selected one pig per pen) for digesta, blood, and intestinal samples collection. The results showed that the average daily feed intake (P = 0.025), average daily gain (P = 0.020), and BW (P = 0.019) increased linearly in the finishing phase of pigs fed with the diets containing Fe. On the other hand, supplementation with different Fe levels in the diet significantly increased serum iron and transferrin saturation concentrations (P < 0.05), goblet cell numbers of duodenal villous (P < 0.001), and MUC4 mRNA expression (P < 0.05). The apparent ileal digestibility (AID) of amino acids (AA) for pigs in the 450 and 600 mg/kg Fe groups was greater (P < 0.05) than for pigs in the control group. In conclusion, dietary supplementation with 450 to 600 mg/kg Fe improved the growth performance of pigs by changing hematological status and by enhancing intestinal goblet cell differentiation and AID of AA.     

Effects of dietary supplementation of fermented garlic powder on growth performance,apparent total tract digestibility,blood characteristics and faecal microbial concentration in weanling pigs

A total of 144 weanling pigs (5.5 ± 0.42 kg) were used in a 5‐week trial to evaluate the effect of fermented garlic powder (FGP) supplementation in weaning pigs. Pigs were randomly allocated to the following four dietary treatments: (i) control (CON; basal diet), (ii) FGP0.5 (CON + 0.5 g/kg FGP), (iii) FGP1 (CON + 1 g/kg FGP), (iv) FGP2 (CON + 2 g/kg FGP). There were six replications with six pigs (three barrows and three gilts) per pen. Pigs fed FGP0.5 treatments increased (p < 0.05) average daily gain (ADG) and average daily feed intake (ADFI) during 3–5 and 0–5 week. No difference was observed on gain/ feed (G/F) ratio in this study. The inclusion of FGP1 and FGP2 treatments increased DM (p < 0.05) digestibility compared with the CON treatment throughout the experiment. The apparent total tract digestibility of N was (p < 0.05) increased by the dietary FGP throughout the experiment. Pigs fed FGP1 and FGP2 treatments increased the lymphocyte concentration (p < 0.05) and RBC concentration compared with the CON group. Dietary FGP decreased the blood total cholesterol (p < 0.05) in comparison with the CON group. The triglyceride (p < 0.05) concentration was decreased in FGP1 and FGP2 treatments compared with those in the CON treatment at the end of the experiment. Pigs fed FGP1 and FGP2 treatments had a lower number of Escherichia coli in faeces on 21 (p < 0.05) and 35 days (p = 0.05) than those in the CON treatment. In conclusion, dietary fermented garlic powder (0.5 g/kg) can improve ADG and ADFI in weanling pigs, but not at higher levels (1 and 2 g/kg). Dietary fermented garlic powder can also increase the nutrient digestibility, lymphocytes and RBC concentrations, but decrease the faecal E. coli concentration in weaning pigs.     

Influence of Bacillus subtilis GCB‐13‐001 on growth performance,nutrient digestibility,blood characteristics,faecal microbiota and faecal score in weanling pigs

The present study investigated the influence of Bacillus subtilis GCB‐13‐001 on growth performance, nutrient digestibility, blood characteristics, faecal microbiota and faecal score in weanling pigs. A total of 120 weaning pigs [(Landrace × Yorkshire) × Duroc; 7.73 ± 0.75 kg (28 days of age)] were randomly allotted into three treatments according to their initial body weight (BW) and gender in a 6‐week experiment. There were 8 replication pens in each treatment, with five pigs/pen. Dietary treatment groups were as follows: (a) basal diet (CON), (b) CON + 0.1% Bacillus subtilis GCB‐13‐001 1 × 10⁸ CFU/kg (T1) and (c) CON + 0.1% Bacillus subtilis GCB‐13‐001 1 × 10⁹ CFU/kg (T2). Days 1 to 7, the BW and ADG with T2 treatment were higher (p < .05) than CON treatment, as well as F:G showed trends in linear reduction (p < .1). Days 8 to 21, the BW and ADG were improved (p < .05) in pigs offered T1 and T2 diets compared with CON diet. Days 22 to 42, BW and ADG were higher (p < .05) in pigs fed T2 diet than CON and T1 diets, and the pigs fed T1 diet had higher BW than CON treatment. Overall, the ADG with the T2 treatment was higher (p < .05) than that with the T1 and CON treatments, and pigs offered T1 treatment had higher (p < .05) ADG than CON treatment. Moreover, F:G ratio were significantly decreased (p < .05) by T2 treatment compared with CON treatment. The faecal Lactobacillus counts were improved, and E. coli counts were reduced (p < .05) in pigs fed T2 diet compared with CON at the end of the experiment. In conclusion, supplementation of 0.1% Bacillus subtilis GCB‐13‐001 1 × 10⁹ CFU/kg has shown a beneficial effect in improving BW, increase ADG, decrease F:G ratio.     

Effects of supplemental humic substances on growth performance, blood characteristics and meat quality in finishing pigs

A total of forty-eight finishing pigs were used to determine the effects of humic substances (HS) on growth performance, blood characteristics, and meat quality. The finishing pigs were assigned randomly by weight to three treatments. The dietary treatments included: 1) Control (CON; basal diet), 2) HS1 (basal diet + 5% humic substances) and 3) HS2 (basal diet + 10% humic substances). Results of the whole experimental period showed that addition of 10% HS to the diet, significantly increased average daily gain (ADG) and gain/feed (G:F) (P < 0.05). At the end of the experiment, the relative lymphocyte counts (% of total white blood cells) of pigs fed HS2 diet were higher (P < 0.05) than that of pigs fed CON diet. The Minolta color parameter a of pigs fed HS2 was similar to that of pigs fed HS1, however, it was higher (P < 0.05) than that of pigs fed CON diet. The inclusion of either 5% or 10% HS significantly decreased backfat thickness (P < 0.05). The marbling score was increased significantly (P < 0.05) when diets were supplemented with HS at a level of 10%. The results of this study suggest that HS might be utilized as a feed additive in the diet. It could improve growth performance, relative lymphocyte counts and meat quality.     

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。     

Effects of different protein sources completely replacing fish meal in low‐protein diet on growth performance,intestinal digestive physiology,and nitrogen digestion and metabolism in nursery pigs

The study compared the effects of selected proteins replacing fish meal in low‐protein diets on piglets’ growth performance, intestinal digestive physiology, and nitrogen digestion and metabolism. Five reduced CP, amino acid (AA)‐supplemented diets containing 4% of either S50, HP300, concentrated degossypolized cottonseed protein (CDCP), P50, or fish meal were assigned to six pens with 11 pigs for a 28‐day study period. Compared with fish meal, dietary proteins did not affect growth performance, apparent total tract digestibility (ATTD) of nutrients, serum hormone levels and biochemical parameters, apparent ileal digestibility (AID) of CP and most AA, colonic short‐chain fatty acid (SCFA) contents, duodenal and ileal morphology, digestive enzyme activity, and pH in small intestine of piglets. However, HP300, CDCP, and P50 decreased (p < 0.05) fecal N excretion per weight gain. AID of Ile in S50 and HP300 and Glu in P50 were improved (p < 0.05), and AID of Gly in other proteins was reduced (p < 0.05). S50 and P50 lowered (p < 0.05) the contents of colonic isobutyric and isovaleric. S50 and HP300 reduced (p < 0.05) jejunal villus height. CDCP increased (p < 0.05) the pepsin activity in stomach. S50, HP300, and CDCP decreased (p < 0.05) pH in the proximal colon. Overall, the selected proteins could completely replace fish meal in low‐protein diet without impairing piglets’ growth via maintaining intestinal digestive physiology, and nitrogen digestion and metabolism.