Effects of whey powder on fermentation quality, nutritive value,
and digestibility of alfalfa silage

The aim of the study was to investigate the effects of whey powder (WP) on the fermentation quality, nutritive value, and digestibility of ensiled alfalfa (Medicago sativa L.). Alfalfa treated with different doses of WP (0, 2, and 4% fresh matter silage) was ensiled in plastic drums for 60 days. The results of the study revealed that the physicochemical composition and fermentation quality of the alfalfa silage improved and that mold growth was inhibited in the groups treated with 2 and 4% WP in comparison to that in the control. Production of CO₂ (day 7) was much lower in silages treated with 2 and 4% WP (3.77 and 1.85 g/kg dry matter (DM), respectively) than in the control group (21.36 g/kg DM). In addition, in vivo dry matter digestibility (DMD) was much higher in the group treated with 4% WP (76.45%) than in the control one (55.82%). In this treatment group, all apparent digestibility of coefficients in vivo from crude nutrient contents and cell wall fractions significantly increased and hence raised the net lactation energy value from 1.18 to 1.31 Mcal/kg DM. However, although the in vitro DMD was higher in the silages treated with WP than in the control one and the dose was significant, there was no strong correlation between in vivo and in vitro values. According to our results, WP could provide an advantage for the conservation of alfalfa silage. In addition, WP could be evaluated as a sustainable silage additive.

ACKNOWLEDGEMENTS

This study was supported by TÜBİTAK 1002 - Short Term R&D Funding Programme (No: 116 O 110) and was included part of Sema ÖZÜRETMEN’s PhD thesis. Those who participated were as follows: SÖ: original draft, conceptualization, investigation, data collection, formal analysis, and writing; HÖ: original draft, conceptualization, project administration, supervision, validation, and editing; HHİ: in vitro digestibility and the correlation between in vitro and in vivo parameters and contributed to writing this article. The authors also thank TÜBİTAK for financial support.

CONFLICT OF INTEREST

The authors declare that there is no conflict of interest.

METADATA IN OTHER LANGUAGES:

Chinese

乳清粉对苜蓿青贮发酵品质、营养价值和消化率的影响

苜蓿，消化率，净能，青贮，乳清粉

本研究旨在研究乳清粉（WP）对青贮苜蓿（Medicago sativa L.）发酵品质、营养价值和消化率的影响。用不同剂量的乳清粉（分别占新鲜苜蓿青贮的0%、2%和4%）处理的苜蓿经塑料桶青贮60天。研究结果表明，与对照组相比，2%和4%乳清粉处理组的苜蓿青贮饲料的理化成分和发酵质量得到改善，霉菌生长受到抑制。添加2%和4%乳清粉（分别为3.77和1.85 g/kg干物质（DM））的青贮饲料的第7天CO2产量远低于对照组（21.36 g/kg DM）。此外，4%乳清粉处理组（76.45%）的体内干物质消化率（DMD）远高于对照组（55.82%）。在该处理组中，所有粗营养成分和细胞壁组分的在体表观消化率系数显著增加，因此泌乳净能值从1.18 Mcal/kg DM提高到1.31 Mcal/kg DM。但是，虽然经WP处理的青贮饲料的体外DMD高于对照组青贮饲料，且剂量显著，但体内和体外数值之间没有强相关性。我们的研究结果显示，乳清粉可为苜蓿青贮保存提供有利条件。此外，乳清粉可以作为一种可持续的青贮饲料添加剂进行评估。

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