Variation in lysine,threonine, and tryptophan availability in meat and bone meal as estimated by the slope‐ratio growth assay technique in growing rats

Meat and bone meal (MBM) is an important protein source used in animal feeds. However, as the composition and availability of amino acids (AAs) in MBM fluctuate markedly, it is important to verify the magnitude of these parameters in different MBMs. In this study, the AA compositions of 19 MBMs were analyzed to confirm variations in lysine (Lys), threonine (Thr), and tryptophan (Trp), then which were compared with those of soybean meal (SBM) and fish meal (FM). Instability in Lys, Thr, and Trp availabilities in six MBMs were also considered after estimation using the slope‐ratio growth assay technique in rats. Variations in AA composition were evaluated using the coefficient of variance (CV: Standard deviation/Mean). CVs for Lys, Thr, and Trp content were 9.40, 11.83, and 18.12 in MBM, 2.71, 2.48, and 3.19 in SBM, and 10.09, 10.44, and 13.47 in FM. Furthermore, means and SDs for Lys, Thr, and Trp availabilities in MBM were 53.3 ± 10.4% (CV: 19.5), 65.9 ± 17.6% (CV: 26.6), and 83.2 ± 11.2% (CV: 13.5), respectively. These results provide the first evidence that variations in MBM AA compositions were 3.5 to 5.7 times higher than those in SBM, but similar to FM, and that the large variation in availability substantially existed.     

伊莎笼养蛋鸡胰岛素样生长因子I限制性片断多态性与骨矿的研究

选择58周龄高产期伊莎笼养蛋鸡90羽,应用PCR扩增鸡IGF-I启动子上游7 kb处基因片段,用PstI消化产生限制性片段长度多态性,分析IGF-I多态性与胫骨、股骨、肱骨骨密度之间的关系。结果表明,伊莎蛋鸡PP、Pp、pp基因型频率分别为0.256、0.311、0.433,P和p等位基因频率分别为0.411 1和0.588 9。方差分析显示,肱骨的骨密度与IGF-I基因多态性相关,PP基因型组的骨密度和骨矿含量均显著大于pp基因型(P<0.05),股骨、胫骨基因型间无显著差异。PP基因型体质量显著大于Pp基因型。表明伊莎笼养蛋鸡IGF-I基因多态性和肱骨骨密度显著相关,P等位基因具有一定的优良骨质指针作用。     

Comparison of bone healing,as assessed by computed tomography,following tibial tuberosity advancement in dogs with and without autogenous cancellous bone grafts

Abstract

AIMS: To objectively compare measures of bone healing, using computed tomography (CT) in dogs following bilateral tibial tuberosity advancement (TTA), between tibiae treated with and without autogenous cancellous bone grafts.

METHODS: Ten dogs with bilateral cranial cruciate ligament disease requiring surgical stabilisation were prospectively recruited to undergo single-session bilateral TTA, with only one, randomly assigned, tibia receiving bone graft in the osteotomy deficit. Bone healing at the osteotomy site was assessed using CT performed 38–70 days post-operatively. CT images were evaluated using both objective measurements of osseous bridging and subjective evaluation by six radiologists. Repeated measures ANOVA was used to compare the objective outcomes between the grafted and non-grafted tibiae.

RESULTS: The mean percentage of the osteotomy deficit bridged at the lateral cortex was greater in grafted (77.6, SD 35.2%) compared to non-grafted (63.0, SD 36.5%) tibiae (p=0.001), but did not differ at the medial cortex (p=0.1). The mean minimum callus width was greater in grafted (7.2, SD 3.3 mm) compared to non-grafted (3.6, SD 2.9 mm) tibiae (p<0.001). There was no difference in mean attenuation (measured in Hounsfield units) of the callus between grafted and non-grafted tibiae (p=0.5). The grafted tibia was deemed to have superior bone healing in 50/60 subjective assessments made by radiologists.

CONCLUSIONS: Superior osseous bridging was detected by CT analysis following TTA using autogenous cancellous bone grafts compared with no graft. This was shown by greater bridging percentage at the lateral cortex and formation of a broader callus. Qualitative assessments made by six radiologists also supported the conclusion that bone healing was improved by use of autogenous cancellous bone graft. CT was a useful method for assessing evidence of bone healing following TTA.

CLINICAL RELEVANCE: These findings justify the application of autogenous cancellous bone graft to augment healing following TTA in dogs.     

Body phosphorus mobilization and deposition during lactation in dairy cows

Dairy cow bone phosphorus (P) mobilization and deposition and their influence on P requirements were studied over the lactation cycle. Thirty Holsteins received a common diet during the dry period and one of the following three dietary treatments that varied in P percentage during the subsequent lactation (44 weeks): (i) 0.36 throughout (constant P, 0.36‐0.36‐0.36), (ii) 0.36 for 30 weeks then 0.29 for 14 weeks (P changed once, 0.36‐0.36‐0.29), and (iii) 0.43 for 10 weeks, 0.36 for 20 weeks, and 0.29 for 14 weeks (P changed twice, 0.43‐0.36‐0.29). Six P balance studies were conducted during the experiment, including one during the dry period and five along lactation, based on P intake, faecal P, urinary P and milk P, when appropriate. Blood samples were taken during balance to analyse bone formation (osteocalcin) and resorption (pyridinoline) marker concentrations and rib biopsies performed to determine bone P content. Phosphorus balance was negative during weeks ?4 to ?1 relative to lactation for all groups and remained negative for cows fed 0.36% P during weeks 1–5, but showed a positive value for cows that received 0.43% P. The balance was close to zero for all groups at weeks 19–23 and showed a clear retention during weeks 38–42; by the end of lactation, cows re‐stored most of the P mobilized earlier. The pattern in P balance was consistent with changes in blood bone metabolism marker concentrations, rib bone P content, and faecal and urinary P concentrations over the experiment, indicating that cows, irrespective of the dietary P treatments received, mobilized P from bone during the late dry period when fed a low‐Ca diet and early lactation, and re‐stored P in late lactation. This dynamic of P metabolism can have important implications for dietary P requirements and ration formulations.     

肥大细胞的发生与分化

肥大细胞来源于骨髓的多向性造血干细胞,其生长和分化受细胞因子和(或)微环境的调节。肥大细胞分结缔组织型和粘膜组织型。成熟的肥大细胞含有异染颗粒,并有脱颗粒作用。     

UNUSUAL HYPERPARATHYROIDISM IN A CAT

A 5 month-old, male, domestic short hair cat was presented with inappetence and vomiting. it was depressed and reluctant to move. The cat had difficulties in keeping the standing position and grossly deformed thighs. Lytic changes and disruption of normal architecture of the bone were observed, involving mainly the femoral diaphyses. An inverse Ca/P ratio and kidney failure were diagnosed. The possibility of whether the bone changes could have been related to primary or secondary renal hyperparathyroidism is discussed.     

Effects of Phytase Addition with or Without a Trace Mineral Premix on Growth Performance,Bone Response Variables,and Tissue Mineral Concentrations in Commercial Broilers

Microbial phytase has been shown to increase the availability of Ca, P, ME, amino acids, and trace minerals in diets of broilers. By increasing the availability of trace minerals, phytase may be able to replace the trace mineral premix in diets for broilers. Therefore, a 43-d floor pen study that included diets with and without phytase and with and without supplemental trace minerals was conducted to evaluate this possibility. The Ca and nonphytate P concentrations were decreased by 0.10% in diets with phytase. Growth performance was not affected in chicks fed diets with or without the trace minerals, but adding phytase had positive effects on growth performance. Removal of the trace minerals had a negative effect on bone strength. Removal of the trace minerals, addition of phytase, or both had variable effects on tissue trace mineral concentrations.     

GAS ACCUMULATION IN THE SUBARACHNOID SPACE RESULTING FROM BLUNT TRAUMA TO THE OCCIPITAL REGION OF A HORSE

A 2-year-old Arabian filly was presented for evaluation after falling backwards. The injury was manifest radiographically by the presence of air within the subarachnoid space of the calvarium and the cervical spinal canal. Radiographic findings resulted from communication of the sphenopalatine sinus with the subarachnoid space as a sequela to a fracture involving the presphenoid bone.