关键词：
Calcium;phosphorus;growing pigs;sodium-dependent Pi absorption;gene expression
摘要：
this experiment, 25 barrows pigs (20.9 +/- 0.95 kg) were fed with diet containing 5 different levels of Ca (0.29, 0.44, 0.60, 0.75 and 0.91%) through different supplementations of limestone powder. Each trial lasted for 35 days long and the pigs were slaughtered on the last day. Jejunum and kidney samples were collected. The amounts of transcription of NaPi-IIc and NaPi-IIa in the samples were measured using fluorescent quantitative PCR assay. According to the NRC, the requirement of Ca for the pigs (20-50 kg) is about 0.6%, so the group of pigs fed with 0.60% Ca level was selected as the calibrator. Compared with Ca level of 0.60%, pigs fed diets with Ca level of 0.44%, 0.75% and 0.91% enhanced mRNA transcription of NaPi-IIc in jejunum (1.49, 13.60 and 7.65) and NaPi-IIa in kidney (2.15, 6.53 and 8.48). Pigs fed with Ca level of 0.29% decreased production of mRNA transcription of NaPi-IIa.
摘要：
Objective: To investigate the effects of dietary net energy (NE) content on the performance of growing pigs fed low-protein diets supplemented with crystalline amino acids. Materials and methods: A total of 144 barrows (22.96 ± 2.72 kg, Experiment One) or 360 barrows (27.80 ± 3.48 kg, Experiment Two) were assigned to six treatments. Diets in both experiments were based on corn and soybean meal, including an unsupplemented high-crude-protein (CP) diet (19.0% CP, 2.50 Meal NE per kg) and five low-CP diets (4% lower CP) supplemented with lysine, methionine, threonine, and tryptophan. For Experiment One, five levels of NE (2.64, 2.58, 2.50, 2.42, and 2.36 Meal per kg) were formulated in the low-protein diets. In Experiment Two, the low-protein diets contained 2.45, 2.40, 2.35, 2.30, and 2.25 Meal NE per kg. Results: In Experiment One, for pigs on low-CP diets with different NE levels, ADG (P < .05) and gain:NE intake (kg per Meal NE) increased linearly with decreasing NE levels (P < .01). In Experiment Two, for pigs on low-CP diets with different NE levels, there was a significant quadratic increase in ADG, gaiN:feed, and gain:NE intake as net energy levels increased from 2.25 to 2.35 Meal NE per kg (P <.05). Implications: Feeding a low-CP, aminoacid-supplemented, corn-soybean-mealbased diet with a proper NE level maximizes the performance of growing pigs. Optimum performance will be obtained if the diet provides approximately 2.40 Meal NE per kg.
摘要：
The present study was conducted to determine the effects of a polysaccharide of Atractylodes macrophala Koidz (PAM) as a dietary additive on growth performance, immunoglobulin concentration and IL-1β expression in weaned piglets. One hundred and twenty Landrace×Yorkshire piglets weaned at 28 days old (body weight 7·5±0·07 kg) were assigned to five treatment groups (three pens/group, eight piglets/pen) fed maize/soybean-based diets supplemented with 0, 3, 6 or 9 g of PAM/kg diet or antibiotics (0·4 g flavomycin/kg+0·13 g olaquindox/kg). The experimental period was 28 days. With increasing PAM supplementation levels, average daily gain was greater (quadratic, P<0·05) and the ratio of amount fed to live weight (LW) gain (feed/gain) improved (quadratic, P<0·05) during days 14–28 and overall, and diarrhoea incidence decreased (linear, P<0·05) during days 14–28. Supplementation of PAM also increased (quadratic, P<0·05) serum concentrations of interleukin (IL)-2 and IL-6 on day 14, and increased (quadratic, P<0·05) IL-1β expression in jejunal mucosa and lymph nodes. Concentrations of PAM between 6 and 9 g/kg presented the strongest bioactivity compared to the control group or antibiotic-fed group. These findings indicate that PAM is effective in improving growth performance and cytokine response, which suggests that PAM can be used as a diet additive for weanling piglets.
作者：
Tang, S. X.*;Gan, J.;Sheng, L. X.;Tan, Z. L.;Tayo, G. O.;...
期刊：
Animal,2008年2(12):1772-1779 ISSN：1751-7311
通讯作者：
Tang, S. X.
作者机构：
[Tang, S. X.; Tan, Z. L.; Sheng, L. X.; Sun, Z. H.; Wang, M.] Chinese Acad Sci, Inst Subtrop Agr, Key Lab Subtrop Agroecol Engn, Changsha 410125, Hunan, Peoples R China.;[Tang, S. X.; Sun, Z. H.] Chinese Acad Sci, Grad Univ, Beijing 100039, Peoples R China.;[Gan, J.] Hunan Agr Univ, Coll Anim Sci & Technol, Changsha 410128, Hunan, Peoples R China.;[Tayo, G. O.] Babcock Univ, Lagos, Nigeria.;[Ren, G. P.] Hunan Yahua Dairy Ind Co Ltd, Changsha 410005, Hunan, Peoples R China.
摘要：
The experiments were conducted to assess how hatching performance is affected by chicken breeds and environment of high altitude and to analyze the vital factor of the low hatchability at a 2,900-m altitude. Eggs of Tibetan and Dwarf chickens were incubated at conditions of normobaric normoxia, normobaric hypoxia, hypobaric hypoxia, and supplemental O2 at high altitude (hypobaric normoxia) during the whole incubation or at 0 to 7, 8 to 14, and 15 to 22 d of incubation, respectively. The results showed that the Tibetan chickens had greater hatchability (79.72%), lower water loss (12.90%), greater relative embryo weight (38.08%), and relative chick weight (68.41%) compared with the Dwarf chickens (31.69, 15.79, 30.71, and 65.21%, respectively) when both of them were incubated at a 2,900-m altitude. The hatchability was 71.60% in Tibetan chicken and 36.23% in Dwarf chicken under the normobaric hypoxia condition. The hatchability of chicken was efficiently increased with supplemental O2. The previous results indicated that the O2 deficit is the main factor resulting in the low hatchability and the poor chick quality of the lowland chicken breed when incubated at a 2,900-m altitude. Breeding chickens for adaptability to hypoxia and supplemental O2 is a good way to improve the hatchability and chick quality at that altitude.
摘要：
Improvement of animal embryo sexing depends upon high-titer serologically detected male (SDM) antibody fragments. SDM sera collected from isogenic C57BL/7 female mice after inoculation with male spleen cells were characterized and used for construction of a recombinant Fab antibody library against SDM antigen, and used for analysis of the binding capacity and specificity to SDM antigen. The heavy-chain Fd and full-length light-chain K were amplified by RT-PCR from a mouse (#6) that'ed high-titer antiserum. The amplified product was inserted into the pComb3 vector followed by co-infections with the help phage VCSM 13 for construction of the phage library, which gave 1.5 x 10(7) colonies with the titer of 3.2 x 10(11) pfu/ml by a recombination rate of 80%. Sequence analysis of the PCR products of plasmid DNA of E5 clones showed that V-H and V-k had common characteristics shared by other known variable region of antibodies. The Fab antibody libraries against SDM antigen were enriched by three cycles of affinity enrichment with male spleen cells, and two cycles of non-specific absorption with female spleen cells. The ELISA results showed that 9 of 15 clones had binding capacity to the SDM antigen. This is the first report on a phage display library of SDM antigen. The mouse Fab antibody library could be used for identifying SDM antigen, and for the development of sex determination of early embryos in mammals. (C) 2007 Elsevier B.V. All rights reserved.
会议名称：
10th International Symposium on Digestive Physiology in Pigs
会议时间：
MAY 25-27, 2006
会议地点：
Vejle, DENMARK
会议主办单位：
Chinese Acad Sci, Inst Subtrop Agr, Changsha 410128, Hunan, Peoples R China.^Cent S Univ, Xiang Ya Med Sch, Mol Biol Res Inst, Changsha 410078, Hunan, Peoples R China.^Hunan Agr Univ, Dept Anim Sci, Changsha 410128, Peoples R China.^Texas A&M Univ, Dept Anim Sci, College Stn, TX 77843 USA.
摘要：
This study was conducted to test the hypothesis that porcine jejunal mucosal cells can degrade all essential amino acids (EAA). Jejunal mucosal cells (primarily enterocytes) were isolated from 50-day-old healthy pigs and incubated at 37 degrees C for 45 min in Krebs buffer containing plasma concentrations of amino acids and one of the following L-[1-C-14]- or L-[U-C-14]-amino acids plus unlabeled tracers at 0.5, 2, or 5 mM: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. There was active transamination of leucine, isoleucine and valine in the cells (1.35-2.5 nmol/mg protein per 45 min at 2 mM), with most (67-71%) of their alpha-ketoacids released into the medium. In contrast, catabolism of methionine and phenylalanine was negligible (0.04-0.05 nmol/mg protein per 45 min at 2 mM) and that of other EAA was completely absent in these cells. These results indicate that intestinal mucosal cells are a site for the substantial degradation of branched-chain amino acids but not other EAA in pigs. (c) 2007 Elsevier B.V. All rights reserved.
摘要：
In the present study, samples of Oesophagostomum spp. collected from pigs from different geographical localities in mainland China were characterized genetically by polymerase chain reaction-linked single-strand conformation polymorphism (PCR-SSCP) and restriction fragment length polymorphism (PCR-RFLP) techniques using genetic markers in the internal transcribed spacers (ITS) of nuclear ribosomal DNA (rDNA). The second internal transcribed spacer (ITS-2) was amplified from 51 individual nodule worms by PCR, and the amplicons were analyzed by SSCP. With the exception of slight microheterogeneity, SSCP analyses displayed two distinct banding profiles that allowed the identification of all Oesophagostomum spp. samples examined into two groups, the first one represented O. dentatum, and the second one may represent O. quadrispinulatum. Then, the entire ITS was amplified from individual samples, and the amplicons were digested with restriction endonuclease Pst I. The results of RFLP analyses were consistent with that of SSCP. Sequence analysis of ITS rDNA supported the identification and differentiation of Chinese Oesophagostomum spp. samples into two species, namely, O. dentatum and O. quadrispinulatum. These PCR-based approaches provide useful complementary tools to traditional methods for the accurate identification of Oesophagostomum spp. (irrespective of developmental stage) and have implications for studying the ecology and population genetic structures of these parasites and for the prevention and control of the diseases they cause.
摘要：
Two digestibility experiments were carried out to comparatively measure true phosphorus (P) digestibility and the faecal endogenous P loss associated with soybean meat (SBM) and wheat middling meal (WM) for growing pigs by the simple linear regression analysis technique and the substitution method. Eight barrows, with an average initial body weight 21 kg, were randomly divided into two groups of four pigs with each group being fed four test diets according to a 4 x 4 Latin square design. Eight maize starch-based diets containing four levels (on dry matter basis) of P (0.20, 0.24, 0.3 6 and 0.42%) and P (0. 181, 0.26, 0.36, and 0.43 %) were formulated from SBM and WM as a sole source of P, respectively. Chromic oxide (0.30%) was used as a digestibility marker. Each experimental period comprised 8 d with a 4-d adaptation and a 4-d collection of faecal samples. Levels of the assay ingredient substitutions had no effects (P > 0.05) on true P digestibility and the endogenous P loss associated with SBM and WM measured by the substitution method. There were no differences (P > 0.05) between the regression technique and the substitution method in measuring the true P digestibility (SBM: 49.4 +/- 3.51 vs. 50.6 +/- 2.4; WM: 63.7 +/- 5.0 vs. 63.2 +/- 5.4%) as well as the faecal endogenous P loss (SBM: 0.62 +/- 0.10 vs. 0.71 +/- 0.11 WM: 0.65 +/- 0.16 vs. 0.70 +/- 0.17 g/kg dry matter intake) for the growing pig. Thus, true P digestibility and the faecal endogenous P loss in feed ingredients for pigs may be measured by using the regression analysis technique and the substitution method. (c) 2007 Elsevier B.V. All rights reserved.
期刊：
Small Ruminant Research,2007年72(1):1-10 ISSN：0921-4488
通讯作者：
Zhang, B
通讯机构：
[Zhang, B ] ;Human Agr Univ, Coll Anim Sci & Technol, Changsha 410128, Peoples R China.
关键词：
small peptide;free amino acids;nitrogen equilibrium;digestibility;goat
摘要：
To study the effects of soybean small peptides (SSP) on nitrogen balance, nutrient digestibility and concentrations of glucose, ammonia and amino acids (AA) in portal veinous plasma (PVP) of goats, eight Xiangdong black goats were used in a 4 x 4 Latin square design. Goats were divided at random into four groups (two goats per group). Each group received the following four treatments in a different order over four treatment periods: SSP in the basic diet by feeding (SSPF), free AA (FAA) in the basic diet by feeding (FAAF), SSP by infusing through the duodenum fistula (SSPI), or FAA by infusing through the duodenum fistula (FAAI). Results showed that nitrogen retention (N-R) in SSPI and SSPF goats was greater than FAAF (P < 0.0 1) and FAAI (P < 0.05) goats, and NR in FAAl goats was greater than FAAF goats (P < 0.05). Apparent protein digestibility (aD(N)) in SSPI goats was significantly greater than FAAF (P < 0.01) and FAAI (P < 0.05) goats, and aD(N) in SSPF and FAAI goats was greater (P < 0.05) than FAAF goats, respectively. Moreover, apparent biological value of protein (aBV) in SSPI goats was greater by 48.71% (P < 0.0 1), 32.71 % (P <0.05) and 20.98% (P < 0.05) than FAAF, FAAl and SSPF goats, respectively, and aBV in SSPF goats was greater (P < 0.05) than FAAF goats. Regarding the digestibility of dietary nutrients, there were no significant differences in crude fat digestibility among the different treatments. However, ME digestibility in SSPI goats was greater by 14.59% (P < 0.05), 10.10% (P > 0.05) and 3.40% (P > 0.05) than FAAF, FAAl and SSPF goats, respectively. But, ME digestibility in FAAF goats was less (P > 0.05) than SSPF goats. Total AA digestibilities in SSPI, FAAI, SSPF and FAAF goats were 78.74%, 69.55%, 73.88% and 64.69%, respectively. By contrast, dietary crude fiber digestibilities in SSPF and FAAF goats were greater than SSPI or FAAI goats. Glucose levels in PVP of SSPI and FAAl goats were greater (P < 0.05) than SSPF and FAAF goats. Ammonia levels in PVP of SSPF and FAAF goats were greater (P < 0.05) than SSPI and FAAl goats. AA level in PVP of SSPI goats was significantly greater than FAAF (P < 0.0 1), FAAl (P < 0.05) and SSPF (P < 0.05) goats, and the levels in SSPF and FAAI goats were greater (P < 0.05) than FAAF goats. Our results suggested that SSP is more effective than FAA in promoting nitrogen balance and protein biological value, and increasing digestibility of dietary nutrients and levels of glucose and amino acids in PVP of goats. Supplying SSP or FAA by infusing through the duodenum fistula was more advantageous than that by feeding. (c) 2006 Elsevier B.V. All rights reserved.
摘要：
Two Schistosoma japonicum vaccine candidate antigens Sj 31 and Sj 32, which have shown particular promise to induce protective immunity in mice, were used to immunize goats by using a DNA priming-protein boosting strategy in present work. DNA vaccine formulations of the two antigens (VRSj31 and VRSj32) were produced and injected intramuscularly twice at a 2-week interval and then recombinant proteins (rSj31 and rSj32) together with Freund Complete Adjuvant (FCA) were used to boost the goats. The experiment was repeated in different batche cercariae. A strong anamnestic antibody response was induced after boost. A significant reduction of liver egg counts and miracidial hatching was showed in both experiments. Significant protections against challenge infection were elicited with 31.6% of percentage reduction for worm recovery in the second experiment and 20.9% in the first experiment, respectively.
