The objective of present study was to investigate changes in salivary components during restraint to identify potential markers of stress. Pigs were subjected to a nasal snare stress (Experiment 1) or an immobilization stress (Experiment 2) by being enclosed in a steel cage. Saliva was collected before, during and after the stress, respectively. Salivary cortisol, serum amyloid A (SAA), haptoglobin (HP), chromogranin A (CgA), amylase, K+, Ca2+ and lactoferrin content were detected. The results showed that in Experiment 1, HP and CgA content increased significantly at 10min during the restraint (P<0.05, P<0.05), in agreement with the significantly increased cortisol and SAA levels (P<0.01, P<0.05), while amylase, K+ and lactoferrin concentrations did not significantly change. In Experiment 2, salivary HP and CgA concentrations also changed significantly during the restraint (P<0.01, P<0.01), yet cortisol, SAA, amylase, K+ and lactoferrin levels did not show obvious change. The results confirmed that salivary HP and CgA content may be useful candidate biomarkers to monitor the physical state in pigs during stress.

The identification of useful biological indicators to monitor the body response before the presentation of clinical diseases has practical value in livestock production. To identify potential biomarkers in pigs at the early stage during inflammation, 12 pigs were intramuscularly injected with 2mL of Lipopolysaccharide (LPS, 15μg/kg BW) or saline. Serum protein expression profiles were detected with two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) techniques. Serum biochemical indicators and acute phase protein (APP) concentrations were analyzed with an automatic biochemical analyzer and ELISA, respectively. Of the serum biochemical indicators, creatinine concentration significantly increased 6h post infection, whereas albumin showed a decreased tendency. The 2-DE and MALDI-TOF mass spectrometry technique detected 17 protein spots representing 10 proteins: α-1-antichymotrypsin, albumin, bovine lactoferrin, serotransferrin, serpin A3-6, immunoglobulin light chain (κ chain, mu chain), complement C3 precursor, zinc-α-2-glycoprotein (ZAG), and ceruloplasmin. Two proteins were selected to confirm the mass spectrometry results, and resulting differences accorded with the proteomics results. Of the four typical acute phase protein (APPs) measured, the C-reactive protein (CRP) and haptoglobin (HP) concentrations increased significantly, while no differences were observed in the pig-major acute phase protein (Pig-MAP) and transthyretin (TTR) contents. The results showed that serum creatinine, CRP, HP, and ten other proteins content changed significantly after LPS injection. Of these proteins, ZAG was first reported in pigs during inflammation. These proteins show great promise as biomarkers to monitor the health status and welfare of pigs during the early stage of LPS-induced inflammation.

To investigate the influence of maternal dietary fat intake on the fatty acid composition and lipid metabolism of progeny subcutaneous fat (SQ), fourteen sows were randomly assigned to a control or high fat (HF) group which received a diet containing 8% corn oil starting seven days before farrowing until weaning. The results showed the fatty acid composition in progeny SQ at weaning age generally demonstrated a similar pattern with the sow milk. However, this pattern was not observed at the finishing stage. The stearoyl-CoA desaturase 1 mRNA and protein levels in the progeny SQ of the HF group decreased at both sampling stages when compared with controls. The study demonstrated that maternal dietary fat during lactation significantly affected the fatty acid composition of progeny SQ at the weaning stage, yet no obvious lasting effect was observed in progeny SQ at the finishing stage.

The diagnostic use of saliva for disease detection and health monitoring is increasing in recent years. To investigate whether the components of saliva change with lipopolysaccharide (LPS) challenge and clarify whether these changes directly relate to the submandibular gland (SMG), 12 pigs were employed in the present study. At 6 h after LPS intramuscular injection, samples including saliva, plasma and SMG were taken. The amylase, cortisol, Immunoglobulin A (IgA), tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β) contents were analyzed by colorimetry, radioimmunoassay or ELISA, respectively. Chromogranin A (CgA) and lactoferrin protein concentrations were detected by western blot. Adenosine triphosphate (ATP) was measured by high-pressure liquid chromatography (HPLC) and the related gene expression was analyzed by reverse transcription polymerase chain reaction (RT-PCR) in SMG. The results showed that LPS treatment increased amylase activity and cortisol concentrations, whereas IL-1β, CgA and lactoferrin concentrations showed a decrease in saliva. Toll-like receptor 2 (TLR2), IL-1β and TNF-α gene expression in SMG increased. Decreased ATP concentration in SMG may be the reason for the opposite changes of IL-1β, lactoferrin and CgA content in the saliva and the SMG. The present study for the first time comprehensively demonstrates that the altered parameters in saliva can indicate the body inflammation in pigs, and they may become useful, noninvasive biomarkers for the evaluation of body state.

The present study was conducted to investigate whether maternal dietary fat affects the fatty acid composition of the longissimus thoracis (LT) muscle in offspring pigs at weaning and finishing stages. Fourteen sows were randomly assigned to a control or a high fat (HF) group. The HF sows received a diet containing 8% corn oil starting seven days before farrowing until weaning. The results showed that a high-fat diet significantly increased the contents of serum-lipid-related indexes in the sows. Although the triglyceride content did not change, the C18:2n−6 content was higher in the colostrum and in the LT muscle of offspring pigs at both investigated stages. The total n−6 content and the n−6/n−3 ratio generally increased. This study demonstrated that maternal dietary fat during lactation affects the fatty acid composition of the LT muscle of progeny at weaning, and can have persistent effects in later life.

<正>本研究分析了杜长大三元杂交猪肌肉注射ACTH后2h内以及连续注射5天后血液中白细胞数目、常规生化指标以及皮质醇、T3、T4、胰岛素等激素,唾液中皮质醇的含量变化,探讨肌肉注射ACTH对生长猪代谢的影响。选用杜长大三元猪16头,8头注射ACTH,8头注射生理盐水,体重20 kg左右时安装颈静脉血管瘘管,恢复一周后进行ACTH肌肉注射实验,采集不同时间点