Introduction

Boron (B) is thought to play key role in proper bone growth and development as well as have some role in regulation of minerals such as calcium (Ca), phosphorus (P) and magnesium (Mg) which act synergistically with vitamin D.

Objective

Present study was planned in two phases to assess the effect of optimum and supranutritional levels of (B) in the form of boric acid (BA) supplementation on bone health of growing cross bred calves.

Method

During Phase-1, twenty four male crossbred calves were blocked into four groups (n = 6) on the basis of their body weight (154.83 ± 8.5 kg), age (7–9 months) and were supplemented with 0 (C), 2.6 (T-1), 5.4 (T-2) and 10.7 (T-3) g BA for appropriate B (0.175 adjustment factor to calculate B form BA) consumption i.e. 0, 100, 200 and 400 ppm in each group respectively, for 90 days. During phase 2, twenty-one male crossbred calves were divided into 3 groups (n = 7) on the basis of their body weight (103.76 ± 4.34 kg) and age (5–8 months). All the groups were on similar dietary regimen with additional supplementation of boric acid as 0 g (control); 3.6 g (200 ppm B; T-1) and 10.8 g (600 ppm B; T-2), respectively for a period of 120 d.

Results

From the first experiment it is reported that plasma levels of bovine alkaline phosphatase (BALP), type I collagen cross-linked N-telopeptide (NTx) and Ca were significantly (P < 0.05) affected in T-2 and T-3 groups as compared to T-1 and control groups. Whereas, plasma osteocalcin (OCN) concentration was found to be higher in T-2 and T-3 groups as compared to control group. However, plasma concentrations (ng/mL) of tartrate resistant acid phosphatase (TRAP) remained unaltered due to dietary treatments. Based on the results, another experiment was conducted to validate the above findings and further to determine the effect of still higher i.e supranutritional levels of BA supplementation on bone health of calves. Results revealed that supplementation of BA in T-2 group had no beneficial effect on bone health as the plasma concentration of BALP, OCN, NTx, 25 (OH) vitamin D and Ca as compared to T-1 group in phase 2. Other possible attributes of bone health i.e. plasma concentration of Mg, P, parathyroid hormone (PTH), and calcitonin were not affected by BA supplementation at any levels.

Conclusion

Overall from present study it can be concluded that supplementation of boric acid 3.6 g/d (equivalent to 200 ppm B) in the diet of growing animals has positive effect on bone health related biomarkers (OCN, NTx and BALP) and supplementation of supranutritional level of BA i.e. 10.8 g (equivalent to 600 ppm B) level had neither additional beneficial nor harmful effect on bone health of calves.

中文翻译：

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热带条件下补充硼酸对杂交犊牛骨骼健康的影响

介绍

硼 (B) 被认为在适当的骨骼生长和发育中起关键作用，并且在调节钙 (Ca)、磷 (P) 和镁 (Mg) 等矿物质方面具有一定作用，这些矿物质与维生素 D 协同作用。

客观的

本研究计划分两个阶段进行，以评估以硼酸 (BA) 形式补充的 (B) 的最佳和超营养水平对生长杂交小牛骨骼健康的影响。

方法

在第一阶段，根据体重 (154.83 ± 8.5 kg)、年龄 (7-9 个月) 将 24 头雄性杂交小牛分成四组 (n = 6)，并补充了 0 (C)、 2.6 (T-1)、5.4 (T-2) 和 10.7 (T-3) g BA 用于适当的 B（计算 B 形式 BA 的调整因子为 0.175）消耗量，即每组分别为 0、100、200 和 400 ppm， 90 天。在第 2 阶段，根据体重（103.76 ± 4.34 kg）和年龄（5-8 个月）将 21 头雄性杂交小牛分为 3 组（n = 7）。所有组都采用类似的饮食方案，并额外补充 0 克硼酸（对照）；分别为 3.6 g（200 ppm B；T-1）和 10.8 g（600 ppm B；T-2），持续 120 天。

结果

根据第一个实验报道，T-2 和 T-3 组的牛碱性磷酸酶 (BALP)、I 型胶原交联 N-端肽 (NTx) 和 Ca 的血浆水平受到显着影响 (P < 0.05)，如与 T-1 组和对照组相比。然而，与对照组相比，发现 T-2 和 T-3 组的血浆骨钙素 (OCN) 浓度更高。然而，由于饮食治疗，抗酒石酸酸性磷酸酶 (TRAP) 的血浆浓度 (ng/mL) 保持不变。基于这些结果，进行了另一项实验以验证上述发现并进一步确定更高的即超营养水平的BA补充剂对小牛骨骼健康的影响。结果显示，在 T-2 组中补充 BA 对骨骼健康没有有益影响，因为 BALP 的血浆浓度，

结论

总的来说，从目前的研究可以得出结论，在生长动物的饮食中补充 3.6 g/d（相当于 200 ppm B）的硼酸对骨骼健康相关的生物标志物（OCN、NTx 和 BALP）和超营养水平的补充具有积极影响BA，即 10.8 克（相当于600 ppm B）的水平对小牛的骨骼健康既没有额外的有益影响，也没有有害影响。