scholarly journals A preliminary study of the effects of cold, frozen, or room temperature storage of commercial feeds on growth performance and feed consumption of juvenile rainbow trout (Oncorhynchus mykiss)

2021 ◽  
Vol 38 (4) ◽  
pp. 411-416
Author(s):  
Umar Khan ◽  
Kadir Seyhan

The storage of commercial feeds in a cool and dry place is a prerequisite management strategy to minimize the deterioration of commercial feeds. This study investigated the effects of feed storage conditions on feed intake and growth performances of juvenile rainbow trout (Oncorhynchus mykiss). A total of 240 juvenile rainbow trout, weighing 8.7–10.5 g, were randomly distributed into four groups. Each group was further subdivided into three replicates with 20 fish in each. The experimental fish were fed to apparent satiation twice daily over a 35-days period using four commercial feeds previously kept at different storage conditions, i.e., room temperature storage (20.8°C), cold storage (10°C), or frozen storages (-1.1°C and -15°C). The feed utilization was assessed by relative feed intake (RFI%) and feed conversion rate (FCR), while growth performance was evaluated by the thermal-unit growth coefficient (TGC) and specific growth rate (SGR). The preliminary findings suggest that the food storage conditions did not significantly affect feed intake and growth performance in juvenile rainbow trout. The findings provide practical information for fish farmers in the management of feed storage, which covers a remarkable proportion of the total production costs in aquaculture facilities.

Animals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 187 ◽  
Author(s):  
Paulo Rema ◽  
Subramanian Saravanan ◽  
Benjamin Armenjon ◽  
Constant Motte ◽  
Jorge Dias

Insects are emerging as a sustainable alternative to fishmeal and fish oil in aquafeeds. This study assessed the effect of graded incorporation levels of defatted yellow mealworm (Tenebrio molitor) protein meal on juvenile rainbow trout (Oncorhynchus mykiss) growth performance, body composition, and apparent nutrient digestibility. The trial comprised five dietary treatments: control diet with 25% fishmeal, and four experimental diets with yellow mealworm protein meal at 5%, 7.5%, 15%, or 25%, which corresponded to a fishmeal replacement of 20%, 30%, 60%, or 100%, respectively. After 90 days, the graded incorporation of insect protein meal led to a significant stepwise increase in final body weight, and a significant improvement of specific growth rate, feed conversion ratio, and protein efficiency ratio compared to the control treatment. Regardless of the incorporation level, the insect protein meal had no effects on fish whole-body composition and apparent digestibility coefficients of dry matter, protein, fat, phosphorus, and energy. Protein, phosphorus, and energy retention significantly increased in fish fed the diets with an insect protein meal. In conclusion, the yellow mealworm protein meal could effectively replace 100% of fishmeal in the diet of juvenile rainbow trout with positive effects on its overall zootechnical performance.


Author(s):  
James Chhay ◽  
BCIT School of Health Sciences, Environmental Health ◽  
Dale Chen ◽  
Hsin Kuo

  Background Kombucha tea is a fermented tea beverage that is mainly consumed for its associated-health benefits. These associated-health benefits may range from detoxifying the body to cancer treating. However, there is little to no scientific evidence that suggests that they work on humans. Similarly, kombucha tea is also prone to post-fermentation. This presents possible ethanol production and accumulation within the tea after packaging which can pose a possible health risk to susceptible population if not properly labelled or controlled. This study will investigate if there is any post-ethanol accumulation in commercially produced kombucha tea products under various storage conditions. Methods The ethanol concentration of 3 different kombucha tea brands (i.e.: Pure+, Health-Ade, and RISE) at various storage conditions (i.e.: no storage, refrigeration, and room temperature) were analyzed using GC-FID to determine post-ethanol accumulation. In addition, NCSS software was used to conduct a statistical analysis on the data to determine whether the 3 different kombucha tea brands exceeded the ethanol regulatory limit and whether the ethanol accumulation was dependent on storage temperatures. Results The mean ethanol concentration for Pure+, Health-Ade, and RISE after refrigeration for 3 weeks were 0.722%, 0.696%, and 0.050% relatively which all showed a slight decrease in ethanol compared to their baseline ethanol levels (i.e.: no storage). Similarly, Pure+, Health-Ade, and RISE mean ethanol concentration after room temperature storage were 1.766%, 1.285%, and 0.794% relatively which indicates ethanol accumulation. Statistical analysis showed that there is a significant difference between room temperature storage and the other 2 storage conditions (i.e.: no storage and refrigeration). Also, only Pure+ and Health-Ade under room temperature storage showed a statistically significant mean ethanol concentration above the regulatory limit. Conclusion Results suggests that room temperature storage of Pure+, Health-Ade, and RISE for 3 weeks increased the ethanol levels significantly while refrigerating them will decrease the ethanol levels slightly which can minimize any potential post-fermentation process from happening. Furthermore, only Pure+ and Health-Ade under room temperature storage for 3 weeks were over the 1% ABV regulatory limit. Lastly, the data obtained from this study can be used to develop guidelines and policies in regulating kombucha tea manufacturers and in educating the public and other regulatory agencies on the matter.  


2015 ◽  
Vol 59 (2) ◽  
pp. 51-61 ◽  
Author(s):  
Allna Piotraszewska-Pająk ◽  
Anna Gliszczyńska-Świgło

AbstractThe colour of honey is one of the most important quality criteria for consumers. The colour depends mainly on the content of plant pigments but the honey consistency, shape, and size of the crystals may also influence the honey colour parameters. It is related to the crystallisation and decrystallisation processes of honey during storage. In the present study, directions of colour changes of honey during storage were evaluated using a tristimulus colorimeter and the CIE 1976 L*a*b* and CIE L*C*hosystems. The effect of time (3 and 9 months) and storage conditions (cold storage, room temperature storage with access to light, and room temperature storage without access to light) on the colour of nectar honeys was investigated. The results obtained showed that both the type of honey and the storage conditions influenced the honey colour parameters. Significant differences in direction and intensity of the colour changes of honey during storage were observed. These differences make it difficult to indicate which storage conditions are optimal to preserve the colour of the honey. It was found that acacia and heather honeys were the most susceptible to colour changes during long-term storage in all of the study’s applied conditions, whereas rape and buckwheat honeys were the most stable in colour parameters.


mSphere ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Yali Liang ◽  
Tianyu Dong ◽  
Minjian Chen ◽  
Lianping He ◽  
Tingzhang Wang ◽  
...  

ABSTRACT The contribution of human gastrointestinal (GI) microbiota and metabolites to host health has recently become much clearer. However, many confounding factors can influence the accuracy of gut microbiome and metabolome studies, resulting in inconsistencies in published results. In this study, we systematically investigated the effects of fecal sampling regions and storage and retrieval conditions on gut microbiome and metabolite profiles from three healthy children. Our analysis indicated that compared to homogenized and snap-frozen samples (standard control [SC]), different sampling regions did not affect microbial community alpha diversity, while a total of 22 of 176 identified metabolites varied significantly across different sampling regions. In contrast, storage conditions significantly influenced the microbiome and metabolome. Short-term room temperature storage had a minimal effect on the microbiome and metabolome profiles. Sample storage in RNALater showed a significant level of variation in both microbiome and metabolome profiles, independent of the storage or retrieval conditions. The effect of RNALater on the metabolome was stronger than the effect on the microbiome, and individual variability between study participants outweighed the effect of RNALater on the microbiome. We conclude that homogenizing stool samples was critical for metabolomic analysis but not necessary for microbiome analysis. Short-term room temperature storage had a minimal effect on the microbiome and metabolome profiles and is recommended for short-term fecal sample storage. In addition, our study indicates that the use of RNALater as a storage medium of stool samples for microbial and metabolomic analyses is not recommended. IMPORTANCE The gastrointestinal microbiome and metabolome can provide a new angle to understand the development of health and disease. Stool samples are most frequently used for large-scale cohort studies. Standardized procedures for stool sample handling and storage can be a determining factor for performing microbiome or metabolome studies. In this study, we focused on the effects of stool sampling regions and stool sample storage conditions on variations in the gut microbiome composition and metabolome profile.


Sign in / Sign up

Export Citation Format

Share Document