Effect of Microbial Phytase on Performance, Nutrient Absorption and Excretion in Weaned Pigs and Apparent Ileal Nutrient Digestibility in Growing Pigs

Zeng, Z.K.,Piao, X.S.,Wang, D.,Li, P.F.,Xue, L.F.,Salmon, Lorraine,Zhang, H.Y.,Han, X.,Liu, L. Asian Australasian Association of Animal Productio 2011 Animal Bioscience Vol.24 No.8

Two experiments were conducted to evaluate the efficacy of Trichoderma reesei derived phytase for pigs fed diets with fixed calcium to total phosphorus ratios (1.5:1). In Exp. 1, 280 weaned pigs (initial BW of $10.32{\pm}1.94$ kg) were allocated to one of five dietary treatments on the basis of weight and gender in a randomized complete block design. Treatments were the low phosphorus (0.6% Ca, 0.4% total P and 0.23% available P) diets supplemented with 0, 250, 1,000, or 2,000 FTU phytase/kg of diet and a positive control diet (PC; 0.85% Ca, 0.58% total P and 0.37% available P). The treatments were applied to seven pens with eight pigs per pen, half male and half female. In Exp. 2, six barrows fitted with ileal T-cannula (initial BW = $35.1{\pm}1.6$ kg) were assigned to three dietary treatments with a double $3{\times}3$ Latin square design. The dietary treatments were the low-phosphorus diet (0.53% Ca, 0.34% total P and 0.14% available P), the low phosphorus diet plus 1,000 FTU phytase/kg and a positive control diet (0.77% Ca, 0.50% total P and 0.30% available P). In Exp. 1, there were linear increases (p<0.01) in weight gain, phosphorus absorption, bone strength, calcium and phosphorus content of fat-free dried bone and plasma phosphorus concentrations with increasing dose rate of phytase. The performance of pigs fed the diets with 250, 1,000, or 2,000 FTU of phytase/kg did not differ from pigs fed the PC diet. Pigs fed diets with 1,000 or 2,000 FTU of phytase/kg did not differ from pigs fed the PC diet in bone characteristics. The apparent digestibility of dry matter, crude protein, ash and energy was not affected by dietary treatment. However, pigs fed the PC diet excreted more fecal phosphorus (g/d, p<0.01) and fecal phosphorus per BW gain (g/kg) than pigs fed the diets with phytase. Phytase linearly decreased (p<0.01) fecal phosphorus excreted per BW gain (g/kg), plasma calcium concentration as well as plasma and bone alkaline phosphatase activity. In Exp. 2, phytase supplementation in the low-P diet increased (p<0.05) the apparent ileal digestibility (AID) of Ca, P, leucine, lysine, phenylalanine, alanine and cysteine, tended to AID of crude protein, isoleucine, threonine, asparagine and serine. In conclusion, the novel phytase originated from Trichoderma reesei is effective in releasing Ca, P, and amino acids from corn soy based diet for pigs.

Intramuscular Administration of Zinc Metallothionein to Preslaughter Stressed Pigs Improves Anti-oxidative Status and Pork Quality

Li, L.L.,Hou, Z.P.,Yin, Y.L.,Liu, Y.H.,Hou, D.X.,Zhang, B.,Wu, G.Y.,Kim, S.W.,Fan, M.Z.,Yang, C.B.,Kong, X.F.,Tang, Z.R.,Peng, H.Z.,Deng, D.,Deng, Z.Y.,Xie, M.Y.,Xiong, H.,Kang, P.,Wang, S.X. Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.5

This study was conducted to determine the effects of exogenous zinc-metallothionein (Zn-MT) on anti-oxidative function and pork quality. After feeding a corn-soybean meal-based diet for two weeks, 48 pigs ($Duroc{\times}Landrace{\times}Chinese\;Black Pig$) were assigned randomly to four groups. Pigs in Group 1 were maintained under non-stress conditions, whereas pigs in Groups 2, 3 and 4 were aggressively handled for 25 min to produce stress. Pigs in Groups 1, 2, 3, and 4 received intramuscular administration of saline (control group; CON), 0 (negative control group; NCON), 0.8 (low dose group; LOW), and 1.6 (high dose group; HIGH) mg rabbit liver Zn-MT per kg body weight, respectively. Pigs were slaughtered at 3 and 6 h post-injection. Zn-MT treatment increased (p<0.05) the activities of superoxide dismutase (SOD) and glutathione-peroxidase (GSH-PX) while decreasing the concentration of malondialdehyde (MDA) in liver. These responses were greater (p<0.05) at 6 h than at 3 h post Zn-MT injection. Zn-MT treatment increased (p<0.05) hepatic SOD mRNA levels in a time and dose-dependent manner and decreased (p<0.05) serum glutamate-pyruvate transaminase and lactate dehydrogenase activities (indicators of tissue integrity). Zn-MT administration decreased (p<0.05) lactate concentration and increased (p<0.05) pH and water-holding capacity in the longissimus thorasis meat. Collectively, our results indicate that intramuscular administration of Zn-MT to pre-slaughter stressed pigs improved tissue anti-oxidative ability and meat quality.

Effects of Post-harvest Storage Duration and Variety on Nutrient Digestibility and Energy Content Wheat in Finishing Pigs

P.P. Guo,P.L. Li,Z.C. Li,H.H. Stein,L. Liu,T. Xia,Y.Y. Yang,Y.X. Ma 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.10

This study was conducted to investigate the effects of post-harvest storage duration and wheat variety on the digestibility and energy content of new season wheat fed to finishing pigs. Two wheat varieties (Shi and Zhong) were harvested in 2013 and stored in the warehouse of the Fengning Pig Experimental Base at China Agricultural University for 3, 6, 9, or 12 mo. For each storage period, 12 barrows were placed in metabolism crates and allotted to diets containing 1 of the 2 wheat varieties in a randomized complete block design. The experimental diets contained 97.34% wheat and 2.66% of a vitamin and trace mineral premix. With an extension of storage duration from 3 mo to 12 mo, the gross energy (GE) and crude protein (CP) of the wheat decreased by 2.0% and 12.01%, respectively, while the concentration of neutral detergent fiber (NDF), acid detergent fiber (ADF) and starch content increased by 30.26%, 19.08%, and 2.46%, respectively. Total non-starch polysaccharide, total arabinose, total xylose and total mannose contents decreased by 46.27%, 45.80%, 41.71%, and 75.66%, respectively. However, there were no significant differences in the chemical composition between the two wheat varieties with the exception of ADF which was approximately 13.37% lower in Shi. With an extension of storage duration from 3 mo to 12 mo, the digestible energy (DE), metabolizable energy (ME) content and the apparent total tract digestibility of GE, CP, dry matter, organic matter, ether extract, ADF and metabolizability of energy in wheat decreased linearly (p<0.01) by 5.74%, 7.60%, 3.75%, 3.88%, 3.50%, 2.47%, 26.22%, 27.62%, and 3.94%, respectively. But the digestibility of NDF changed quadratically (p<0.01). There was an interaction between wheat variety and storage time for CP digestibility (p<0.05), such that the CP digestibility of variety Zhong was stable during 9 mo of storage, while the CP digestibility of variety Shi decreased (p<0.05). In conclusion, the GE, DE, and ME of wheat was stable during the first 3 to 6 mo of post-harvest storage, and decreased during the following 6 to 12 mo of storage under the conditions of this study.

Correlations between Heterozygosity at Microsatellite Loci, Mean d² and Body Weight in a Chinese Native Chicken

Liu, G.Q.,Jiang, X.P.,Wang, J.Y.,Wang, Z.Y. Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.12

A total of two hundred twenty eight half-sib chickens were scored for allele size at 20 microsatellite loci to estimate individual heterozygosity and mean $d^2$. The averages of microsatellite heterozygosity, allele per locus and mean $d^2$ were 0.39, 3.6 and 49, respectively. The body weight was measured biweekly from birth to twelve weeks of age. Gompertz function was assumed to simulate body weight and to estimate the growth model parameters. Due to sex effect on body weight, the regression of body weight on heterozygosity as well as on mean $d^2$ in males and females was analyzed separately in the present study. Positive correlations were found between microsatellite heterozygosity and body weight in males and females (p<0.05). Positive correlation also observed between individual heterozygosity and simulated maximum daily gain estimated from Gompertz function in female chickens (p<0.05). There were no significant correlations between mean $d^2$ and body weight. The results suggest that local effect hypothesis could explain the correlations between heterozygosity and fitness-related traits in the domesticated chicken population, rather than the general effect hypothesis does.

Effects of Astragalus Polysaccharides, Achyranthes bidentata Polysaccharides, and Acantbepanax senticosus Saponin on the Performance and Immunity in Weaned Pigs

Kang, P.,Xiao, H.L.,Hou, Y.Q.,Ding, B.Y.,Liu, Y.L.,Zhu, H.L.,Hu, Q.Z.,Hu, Y.,Yin, Y.L. Asian Australasian Association of Animal Productio 2010 Animal Bioscience Vol.23 No.6

Two trials were conducted to study the effects of two Chinese herbal polysaccharides, Astragalus polysaccharides (APS) and Achyranthes bidentata polysaccharides (ABPS), and one Chinese herbal saponin, Acantbepanax senticosus saponin (ASS), on the immunity and growth performance of weaned pigs. Experiment 1 was a 14-day growth assay, in which 32 weaned pigs were randomly allocated to one of four dietary treatments: i) 0.05% talcum powder control; ii) 0.05% APS; iii) 0.05% mixture of APS and ASS in a 1:1 ratio by weight; and iv) 0.05% mixture of APS, ASS, and ABPS in a ratio of 1:1:1 by weight. Blood samples were collected on day 14 to determine plasma parameters. Feed intake, body weight gain, and feed efficiency were also determined. Experiment 2 was a 21-day immunity assay, in which 16 weaned pigs were randomly allotted to one of two dietary treatments: i) 0.05% talcum powder control; and ii) 0.05% mixture of APS and ASS in a 1:1 ratio by weight. On day 21, pigs were challenged with lipopolysaccharide (LPS) and 3 h later blood samples were collected and analyzed for lymphocyte proliferation as well as interleukin 6 (IL-6), insulin-like growth factor 1 (IGF-1), growth hormone (GH), and cortisol levels. In Experiment 1, feeding Chinese herbal polysaccharides and saponin increased growth performance of the pigs. The effects of the mixture of APS and ASS were especially notable, as there was a significant improvement in growth performance compared with the control (p<0.05). The plasma concentration of immunoglobulin G (IgG), nitric oxide (NO), and nitric oxide synthase (NOS) were increased in all treatments groups, with the mixture of APS and ASS increasing the level of IgG and NOS significantly (p<0.05), compared with the control. There was no difference in the NO level between the control and treatment groups (p>0.05). In Experiment 2, Chinese herbal polysaccharides and saponin showed immunostimulating effects. The level of cortisol, GH, and IGF-I were significantly increased (p>0.05), and the level of IL-6 showed a significant decrease (p<0.05) in the APS and ASS treatment after the LPS challenge. The mixture of APS and ASS could stimulate the blood lymphocyte proliferation significantly whether the LPS was injected or not (p<0.05). These results show that Chinese herbal extracts can improve growth performance and stimulate immunity of weaned pigs. A mixture of APS and ASS, compared with APS alone, could be a new kind of immunostimulant for weaned pigs, which could result in greater positive effects on their growth performance and immunity.

Investigation of Gene and Microsatellite Heterozygosities Correlated to Growth Rate in the Chinese Meishan Pig

X. P. Jiang,G. Q. Liu,Y. Z. Xiong 아세아·태평양축산학회 2005 Animal Bioscience Vol.18 No.7

A total of 130 Chinese Meishan piglets were scored for their genotypes at five gene loci and five microsatellite loci. The average gene heterozygosity was 0.3338 and the average microsatellite heterozygosity was 0.2954, and the heterozygosity of the overall ten loci was 0.3146. The data of birth weight (BW) and body weight on day 35 (W35) were collected, average daily gain (ADG) for each individual was computed as the slope from the regression of weight on age. There was no significant correlation between individual heterozygosity and birth weight (p>0.05). Significant regressions were observed between ADG and the heterozygosity of loci (p<0.01). Similar results were observed in W35 and loci heterozygosity (p<0.01). Heterozygosity at these ten loci explained 43.62% of the total variation in ADG and 45.48% in W35. Significant correlations existed not only in the function of gene loci but also in neutral microsatellite loci, so it indicated that associative overdominance affected piglet growth significantly.

Effects of Post-harvest Storage Duration and Variety on Nutrient Digestibility and Energy Content Wheat in Finishing Pigs

Guo, P.P.,Li, P.L.,Li, Z.C.,Stein, H.H.,Liu, L.,Xia, T.,Yang, Y.Y.,Ma, Y.X. Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.10

This study was conducted to investigate the effects of post-harvest storage duration and wheat variety on the digestibility and energy content of new season wheat fed to finishing pigs. Two wheat varieties (Shi and Zhong) were harvested in 2013 and stored in the warehouse of the Fengning Pig Experimental Base at China Agricultural University for 3, 6, 9, or 12 mo. For each storage period, 12 barrows were placed in metabolism crates and allotted to diets containing 1 of the 2 wheat varieties in a randomized complete block design. The experimental diets contained 97.34% wheat and 2.66% of a vitamin and trace mineral premix. With an extension of storage duration from 3 mo to 12 mo, the gross energy (GE) and crude protein (CP) of the wheat decreased by 2.0% and 12.01%, respectively, while the concentration of neutral detergent fiber (NDF), acid detergent fiber (ADF) and starch content increased by 30.26%, 19.08%, and 2.46%, respectively. Total non-starch polysaccharide, total arabinose, total xylose and total mannose contents decreased by 46.27%, 45.80%, 41.71%, and 75.66%, respectively. However, there were no significant differences in the chemical composition between the two wheat varieties with the exception of ADF which was approximately 13.37% lower in Shi. With an extension of storage duration from 3 mo to 12 mo, the digestible energy (DE), metabolizable energy (ME) content and the apparent total tract digestibility of GE, CP, dry matter, organic matter, ether extract, ADF and metabolizability of energy in wheat decreased linearly (p<0.01) by 5.74%, 7.60%, 3.75%, 3.88%, 3.50%, 2.47%, 26.22%, 27.62%, and 3.94%, respectively. But the digestibility of NDF changed quadratically (p<0.01). There was an interaction between wheat variety and storage time for CP digestibility (p<0.05), such that the CP digestibility of variety Zhong was stable during 9 mo of storage, while the CP digestibility of variety Shi decreased (p<0.05). In conclusion, the GE, DE, and ME of wheat was stable during the first 3 to 6 mo of post-harvest storage, and decreased during the following 6 to 12 mo of storage under the conditions of this study.

Phenotypic and Genetic Parameters for Inosine Acid in Relation to Carcass and Meat Quality Traits in Pigs

Jiang, X.P.,Liu, G.Q.,Xiong, Y.Z.,Ding, J.T.,Xie, K.Z.,Zhang, J.Q.,Zuo, B. Asian Australasian Association of Animal Productio 2003 Animal Bioscience Vol.16 No.2

A total of 135 F2 finishing pigs (65 barrows and 69 gilts) from resource population (Large White${\times}$Meishan) were slaughtered at about 87.8 kg BW. Contents of inosine acid (IMP) and carnine (HR) in muscle were assayed by HLPC and genetic parameters for IMP content and HR content were estimated using full sibs model. There was significant sex effect on IMP content(p<0.05), $3.561{\pm}0.077mg/g$ for gilt and $3.287{\pm}0.085mg/g$ for barrow. Heritability estimates for IMP and HR content were 0.127 and 0.357, respectively. The phenotypic correlation between IMP content and HR was 0.335, pH (A) 0.024, water lose rate (WLR) -0.069, intramuscular fat (IMF) -0.214, average marbling score (MARB) -0.143, average backfat measurements (AVBF) -0.084 and average color value (CV) -0.156, respectively. The result indicated that inosine acid content in meat might be retained or slightly improved by reducing backfat depth in pig breeding.

Limitation of effective length method and codified second-order analysis and design

S. L. Chan,Y. P. Liu,Z. H. Zhou 국제구조공학회 2005 Steel and Composite Structures, An International J Vol.5 No.3

The effective length method for flexural (column) buckling has been used for many decades but its use is somewhat limited in various contemporary design codes to moderately slender structures with elastic critical load factor (λcr) less than 3 to 5. In pace with the use of higher grade steel in recent years, the influence of buckling in axial buckling resistance of a column becomes more important and the over-simplified assumption of effective length factor can lead to an unsafe, an uneconomical or a both unsafe and uneconomical solution when some members are over-designed while key elements are under-designed. Effective length should not normally be taken as the distance between nodes multiplied by an arbitrary factor like 0.85, 1.0, 2.0 etc. Further, the classification of non-sway and sway-sensitive frames makes the conventional design procedure tedious to use and, more importantly, limited to simple regular frames. This paper describes the practical use of second-order analysis with section capacity check allowing for P-δ and P- Δ effects together with member and system imperfections. Most commercial software considers only the P-Δ effect, but not member and frame imperfections nor P-δ effect, and engineers must be very careful in their uses. A verification problem is also given for validation of software for this type of powerful second-order analysis and design. It is a trend for popular and advanced national design codes in using the second-order analysis as a norm for analysis and design of steel structures while linear analysis may only be used in very simple structures.

Genetic Status of ESR Locus and Other Unidentified Genes As sociated with Litter Size in Chinese Indigenous Tongcheng Pig Breed after a Long Time Selection

Zhu, M.J.,Yu, M.,Liu, B.,Zhu, Z.Z.,Xiong, T.A.,Fan, B.,Xu, S.P.,Du, Y.Q.,Peng, Z.Z.,Li, K. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.5

The Tongcheng pig breed is a famous Chinese indigenous breed. The Ministry of Agriculture of China has filed it as 1 of 19 national key conservation breeds selected from more than 100 Chinese indigenous pig breeds in 2000. In order to improve the reproductive performance, it has been intensively selected to increase the litter size for about 10 years. The population randomly sampled from conservation nucleus of eight families in the Tongcheng pigs was genotyped for identification of their estrogen receptor locus polymorphisms with the PCR-RFLPs method. Only AB heterozygotes and BB homozygotes were detected, and $X^2$ test demonstrated that the locus was in disequilibrium at a significant level (p<0.05). In the present paper, the litter sizes in different parities were regarded as different traits. Holistic status of other unspecific and unidentified genes was estimated by using the statistical methods. Coefficients of kurtosis and skewness showed that the litter size still presented segregating characteristic in the 2nd, 5th, 7th, 8th and 9th parities. Analysis of homogeneity of variance between families confirmed the results for the 5th, 7th and 8th parities. The heritability of litter size for the 1st to 10th parities was estimated with paternal half-sib model and individual estimated breeding values (EBVs) were evaluated by a single trait animal model as well. We found that the averages of EBVs for litter size in each parity did not differ significantly between genotypes, despite the significant difference for original phenotype records in the 3rd, 4th and 5th parities (p<0.05 or p<0.01). The results may be explained by the deduction that the polymorphisms of ESR locus are no longer the important genetic base of litter size variation when the frequency of allele B accumulated in the experience of selection procedure, and further conferring that there exist special genes associated with litter size in the recent Tongcheng pigs population can be made.