Zinc oxide quantum dots as an alternative to conventional ZnO: Physicochemical characterization and its application in weaned piglets.
Zinc oxide quantum dots at doses of 250 and 500 mg/kg improved growth and reduced diarrhea in piglets, suggesting they could be a viable alternative to high-dose zinc oxide.
Where it sits
this study against the rest of the adipotide (prohibitin-tp01) corpusSummary and findings
This study investigated the potential of zinc oxide quantum dots (ZnO QDs) as an alternative to high-dose zinc oxide (ZnO) in weaned piglets. A total of 150 piglets were divided into groups receiving various doses of ZnO QDs or ZnO over a 28-day trial. Results indicated that ZnO QDs improved average daily gain and reduced diarrhea incidence compared to the control group.
Abstract
High-dose zinc oxide (ZnO) is effective in preventing diarrhea in piglets, but its use is limited by several concerns, including impaired intestinal barrier function, increased bacterial resistance, and the risks of heavy metal residues and environmental pollution. This study aimed to investigate whether zinc oxide quantum dots (ZnO QDs), a novel nanomaterial with diameters of less than 10 nm, could serve as an alternative to ZnO. In vitro, ZnO QDs were used to characterize the structure and evaluate antibacterial activity. In vivo, a total of 150 piglets (24 ± 1 d old, 7.45 ± 0.41 kg weight) were randomly divided into five groups: negative control group (CON), positive control group (ZnO; 1500 mg/kg Zn as ZnO), and 3 levels of ZnO QDs groups (250, 500, or 750 mg/kg Zn as ZnO QDs). Each group consisted of 10 replicates of 3 piglets for a 28-d trial. Results showed that ZnO QDs (size = 3.82 ± 0.38 nm, specific surface area = 17.65 m<sup>2</sup>/g) exhibited superior antibacterial activity in vitro due to their small size, large surface area, and high Zn release when compared to ZnO (size = 239.48 ± 78.02 nm, specific surface area = 0.91 m<sup>2</sup>/g). In vivo, the ZnO, ZnO QDs 250 and ZnO QDs 500 groups improved average daily gain (ADG; <i>P =</i> 0.003), while only the ZnO QDs 500 group decreased the feed to gain ratio (F/G; <i>P =</i> 0.038) compared with the CON group. Supplementation with ZnO QDs at 250 to 750 mg/kg also reduced diarrhea incidence in piglets (<i>P</i> < 0.05), with effects comparable to those observed with 1500 mg/kg ZnO. Dietary ZnO QDs supplementation mitigated Zn emissions and prevented hepatic Zn accumulation compared with high-dose ZnO (<i>P</i> < 0.001). Moreover, both ZnO QDs and ZnO improved the apparent digestibility of dry matter, organic matter, crude protein, and ether extract, enhanced digestive enzyme activities, and upregulated <i>SGLT1</i> mRNA expression in the jejunal mucosa (<i>P</i> < 0.05). In addition, supplementation of 250 and 500 mg/kg ZnO QDs promoted jejunal development, and 500 mg/kg ZnO QDs increased microbial α-diversity indices and enriched beneficial bacteria such as <i>norank_f_Muribaculaceae</i> in the colon (<i>P</i> < 0.05). Conversely, high-dose ZnO hindered intestinal development and decreased <i>Lactobacillus</i> abundance and increased <i>Escherichia-Shigella</i> and <i>Treponema</i> abundances (<i>P</i> < 0.05), all of which are detrimental to the intestinal health of piglets. In conclusion, dietary ZnO QDs at 250 and 500 mg/kg effectively promoted growth, prevented diarrhea, reduced Zn emissions, improved nutrient utilization, and regulated gut microbiota, suggesting their suitability as an alternative to high-dose ZnO. This study provides a novel approach to prevent diarrhea in piglets.
Background
This paper addresses the concerns associated with high-dose zinc oxide (ZnO) in preventing diarrhea in piglets, including impaired intestinal barrier function and environmental pollution. Prior studies have indicated that while ZnO is effective, its drawbacks necessitate alternative solutions. The introduction of zinc oxide quantum dots (ZnO QDs) as a novel nanomaterial could potentially address these issues, making this study relevant for improving animal health and welfare.
Methods
The study utilized a randomized design involving 150 weaned piglets (24 ± 1 d old, 7.45 ± 0.41 kg weight) divided into five groups: a negative control, a positive control receiving 1500 mg/kg Zn as ZnO, and three groups receiving ZnO QDs at 250, 500, or 750 mg/kg Zn. Each group consisted of 10 replicates of 3 piglets for a 28-day trial. Primary outcomes included average daily gain (ADG), feed to gain ratio (F/G), and diarrhea incidence.
Results
The primary endpoint showed that average daily gain (ADG) improved with ZnO, ZnO QDs 250 and ZnO QDs 500 groups, P = 0.003. Additionally, the ZnO QDs 500 group exhibited a decreased feed to gain ratio (F/G), P = 0.038. Diarrhea incidence was significantly reduced with ZnO QDs supplementation at 250 to 750 mg/kg, P < 0.05. ZnO QDs also mitigated Zn emissions and prevented hepatic Zn accumulation compared to high-dose ZnO, P < 0.001.
Interpretation
The findings suggest that ZnO QDs may offer advantages over traditional ZnO, particularly in promoting growth and reducing diarrhea in piglets. However, while the statistical significance of the results is noted, the clinical relevance may be limited by the small sample size and short duration of the study. Additionally, the effects observed may not be generalizable beyond the specific population of piglets studied.
Key findings
- ZnO QDs size = 3.82 ± 0.38 nm, specific surface area = 17.65 m²/g.
- Average daily gain (ADG) improved with ZnO, ZnO QDs 250 and ZnO QDs 500 groups, P = 0.003.
- Feed to gain ratio (F/G) decreased in the ZnO QDs 500 group compared with the CON group, P = 0.038.
- Diarrhea incidence was reduced with ZnO QDs supplementation at 250 to 750 mg/kg, P < 0.05.
- ZnO QDs supplementation mitigated Zn emissions and prevented hepatic Zn accumulation compared with high-dose ZnO, P < 0.001.
Limitations
- small n=150 piglets
- 28-day trial duration may not reflect long-term effects
- specific population limits generalizability
- no assessment of long-term health outcomes