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This study examined the effects of road transportation on metabolic and immunological responses in dairy heifers. Twenty Holstein heifers in early pregnancy were divided into non‐transported (NT; n = 7) and transported (T; n = 13) groups. Blood was collected before transportation (BT), immediately after transportation for 100 km (T1) and 200 km (T2), and 24 h after transportation (AT). The T heifers had higher (P < 0.05) blood cortisol and non‐esterified fatty acid concentrations after T1 and T2 than did NT heifers. By contrast, the T heifers had lower (P < 0.05) serum triglyceride concentrations after T1 and T2 than had the NT heifers. The serum cortisol and triglyceride concentrations returned (P > 0.05) to the BT concentrations at 24 h AT in the T heifers. The granulocyte‐to‐lymphocyte ratio and the percentage of monocytes were higher (P < 0.05) after T2 in the T heifers than in the NT heifers, suggesting that transportation stress increased the numbers of innate immune cells. T heifers had higher (P < 0.01) plasma haptoglobin concentrations than NT heifers 24 h AT. In conclusion, transportation increased cortisol secretion and was correlated with increased metabolic responses and up‐regulation of peripheral innate immune cells in dairy heifers.  相似文献   
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Tropical Animal Health and Production - A study was conducted with the objective to characterize the morphology of Socorro Island Merino sheep. A total of 67 sheep, 62 females, 26 purebred and 36...  相似文献   
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To clone adiponectin (ADPN) gene from Shaziling porcine adipocyte and construct its eukaryotic expression vector, total RNA was extracted from subcutaneous fatty tissue. One pair of specific primers was designed by Primer 5.0 software according to the sequence of ADPN gene of porcine available in GenBank. The ADPN gene was amplified by PCR from cDNA and cloned into pMD18‐T vector to construct recombinant clonal vector pMD‐ADPN, sequenced and analysed. A recombinant expression plasmid pPICZaA‐ADPN was constructed by subcloning the cloned ADPN gene into the linearized pPICZaA vector. Then, the plasmid pPICZaA‐ADPN was expressed in Pichia pastoris (GS115) by electrotransformation. Western blot and Bradford analysis were used to determine the target protein induced by methanol. Results showed that the genome size of ADPN was 732 bp and encoded 244 amino acid, the nucleotide sequence of ADPN shared 100% identity with that of porcine available in GenBank. Western blot and Bradford analysis showed that the recombinant ADPN was expressed in GS115 correctly and has certain immune activity. The expression level of ADPN was 28.5 μg/ml. In conclusion, the recombinant ADPN could express in eukaryotic expression vector pPICZaA‐ADPN constructed in this study effectively.  相似文献   
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Objective : The purpose of this study was to investigate whether implantable loop recorders could be used in the diagnosis of unexplained collapse in dogs. Methods : The medical records of six dogs presented to the University of Liverpool Small Animal Teaching Hospital between May 2003 and October 2006 for further evaluation of intermittent syncopal episodes, collapse or episodic weakness, were reviewed. All these dogs underwent standard investigations and had implantable loop recorders placed. Results : A provisional diagnosis of supraventricular tachycardia was made in one dog, and diagnoses of exclusion of arrhythmogenic right ventricular cardiomyopathy and idiopathic epilepsy was made in two dogs. One dog suffered no further syncopal episodes, a diagnosis was not reached in another dog and the final dog was lost to follow‐up. Clinical Significance : The implantable loop recorder can be used successfully for the diagnosis of unexplained collapse in dogs.  相似文献   
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1. Observations of vigorous wing movements and measurements of bone strength were compared in two experiments with birds in three different housing systems: a semi-intensive alternative system under development, a battery cage system and a deep-litter system. 2. A significant effect of housing system on the frequency of vigorous wing movements was found. The highest frequency was seen in the deep-litter system, about half this number in the alternative system, while in the battery cages they were never observed. 3. Corresponding to this a reduction in humerus strength of 9% was found in hens from the alternative system and of 45% in hens from cages, compared with deep-litter. A reduction in tibial breaking strength was also found in caged hens, when compared to deep-litter hens. 4. Keeping hens in cages thus restricts their movements, especially wing movements, to the degree that bone strength is greatly reduced. 5. This has welfare implications, for hens with low bone breaking strength risk a possibility of breakage, especially when handled and transported. When alternative systems are designed opportunities for movement in the three dimensions should be considered.  相似文献   
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