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991.
  1. The aim of this study, comprising two experiments, was (1) to determine in Experiment 1 the relationship of incremental dietary P (phosphorus) content on precaecal digestible P in male broilers and (2) to determine in Experiment 2 the precaecal P digestibility of various inorganic P sources at marginal levels of P supply.

  2. In Experiment 1, a total of 260 male Ross 308 broilers were divided into groups of 10 birds per pen resulting in 8 replicates for treatment 1 and 6 replicates for treatments 2–4. Experimental diets were formulated to contain 4 incremental concentrations of digestible P by means of increasing concentrations of monocalcium phosphate (MCP). In the second experiment, 480-d-old male Ross 308 broilers were divided in groups of 12 birds per pen resulting in 16 replicates for the basal diet and 6 replicates for each test diet. A total of 4 inorganic P sources, MCP, monodicalcium phosphate (MDCP), dicalcium phosphate (DCP) and defluorinated phosphate (DFP) were added to the basal diet to determine the precaecal P digestibility. Three of the 4 inorganic P sources (MCP, MDCP and DCP) represented a mix of batches from different producers. At the end of both experiments, the chyme of the posterior part of the small intestine was collected. Digestibility of P and Ca was determined using titanium dioxide as indigestible marker.

  3. In Experiment 1, a reduction in precaecal digestibility of P was observed above an estimated precaecal digestible dietary P concentration of 4.8 g/kg.

  4. The precaecal P digestibility of the tested inorganic P sources in Experiment 2 was 78.3% for MCP, 59.0% for DCP, 70.7% for MDCP and 31.5% for DFP.

  相似文献   
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A three‐year‐old, female neutered, Dobermann pinscher was presented for investigation of lethargy, episodic collapse, ataxia and myxoedema. Primary hypothyroidism and primary cortisol‐deficient hypoadrenocorticism were diagnosed based on history, physical examination and compatible hormonal analysis. Increased serum concentrations of thyroglobulin autoantibodies and 21‐hydroxylase autoantibodies indicated an immune‐mediated aetiology. The case was complicated by lymphadenopathy with hand‐mirror lymphocytes, classically identified in lymphoma. A polymerase chain reaction test for antigen receptor rearrangement indicated polyclonality and therefore reactive lymphadenopathy. The dog's clinical signs resolved following introduction of levothyroxine and prednisolone. Prioritising the problem‐based approach in this case facilitated the diagnosis of hypoadrenocorticism in addition to hypothyroidism due to the persistence of clinical signs despite thyroxine replacement. Importantly, atypical adrenal gland dysfunction was not misinterpreted as inadequate therapeutic response to thyroxine supplementation. The observation that polyglandular endocrinopathy type II can occur in dogs suggests that in dogs with a suboptimal response to treatment for hypothyroidism or hypoadrenocorticism comorbid endocrinopathies should be investigated.  相似文献   
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Four partially intact, female dogs with a median age of 6 · 5 years were presented to Angell Animal Medical Center for laparoscopic treatment of ovarian remnant syndrome. Dogs were positioned in dorsal recumbency and a three‐port laparoscopic technique was used to identify and remove en bloc any abnormal tissue in the area of the ovarian pedicles. None of the dogs required conversion to open coeliotomy and there were no major complications. Abnormal tissue, including granulosa thecal cell tumour (n = 1), was identified bilaterally in three dogs and unilaterally in one dog. Clinical signs associated with ovarian remnant syndrome resolved in all dogs following surgery.  相似文献   
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Tendons regenerate poorly due to a dense extracellular matrix and low cellularity. Cellular therapies aim to improve tendon repair using mesenchymal stem cells and tenocytes; however, a current limitation is the low proliferative potential of tenocytes in cases of severe trauma. The purpose of this study was to develop a method useful in veterinary medicine to improve the differentiation of Peripheral Blood equine mesenchymal stem cells (PB-MSCs) into tenocytes. PB-MSCs were used to study the effects of the addition of some growth factors (GFs) as TGFβ3 (transforming growth factor), EGF2 (Epidermal growth factor), bFGF2 (Fibroblast growth factor) and IGF-1 (insulin-like growth factor) in presence or without Low Level Laser Technology (LLLT) on the mRNA expression levels of genes important in the tenogenic induction as Early Growth Response Protein-1 (EGR1), Tenascin (TNC) and Decorin (DCN). The singular addition of GFs did not show any influence on the mRNA expression of tenogenic genes whereas the specific combinations that arrested cell proliferation in favour of differentiation were the following: bFGF2 + TGFβ3 and bFGF2 + TGFβ3 + LLLT. Indeed, the supplement of bFGF2 and TGFβ3 significantly upregulated the expression of Early Growth Response Protein-1 and Decorin, while the use of LLLT induced a significant increase of Tenascin C levels. In conclusion, the present study might furnish significant suggestions for developing an efficient approach for tenocyte induction since the external administration of bFGF2 and TGFβ3, along with LLLT, influences the differentiation of PB-MSCs towards the tenogenic fate.  相似文献   
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