Reduction of environmental risks and improving livestock productivity in Mixed Crop-Livestock Systems with cheap byproducts of berry fruits

Reduction of environmental risks and improving livestock productivity in Mixed Crop-Livestock Systems with cheap byproducts of berry fruits

Summary

Environmental and health risks associated with the products from Mixed Crop-Livestock Farming (MCLF) systems due to cross contamination with zoonotic bacterial pathogens are major safety concerns. Current intervention strategies such as, administration of antibiotics for livestock production are of limited use due to the emergence of resistant pathogens and/or presence of antibiotic residues in foods. Further, organic MCLFs are not allowed to use antibiotics or chemicals. As a result, alternative approaches are critical to address the current issue. Natural bioactive compounds from plant origin can play crucial role in such a situation. Berry fruits are well documented as sources of natural antimicrobials which primarily consist of polyphenols and their bioactive derivatives. These antimicrobial components are present in berry byproduct called “pomace”, which are primarily seeds and skins of fruits after juice is squeezed out. These components show promising antimicrobial activity against various zoonotic pathogens especially Campylobacter and Salmonella. In this project, we approach to use bioactive extracts from berry pomaces as an alternative intervention to reduce pathogenic bacterial colonization in poultry gut. These bioactive extracts will also replace chemical growth promoters in livestock farming system, improve animal health and increase productivity. Microbiological quality of the compost is also expected to improve resulting in reduced prevalence of cross contamination of crops with zoonotic bacterial pathogens. We believe, this proposed intervention will mitigate pathogen associated risks in the farm environment and its products and, therefore, increase profitability especially in the MCLFs. So far, we have completed all the proposed three in vivo trials in chick model. We received the IACUC approval for the animal experiment on December 11, 2014. We started Trial-1 on March 12, 2015; Trial-2 on June 1, 2015; and Trial-3 on October 6, 2015. We are still carrying out the sample processing from the 3^rd trial and analyzing the data for publication. Data from the first trial has been presented in IAFP 2015 conference. For completion of the project, we have been approved for a no-cost extension upto June 30, 2016 (approved on October 19, 2015).

Objectives/Performance Targets

In this study, we proposed to:

• • Assess the effects of berry pomace extracts (BPE) on the colonization of Campylobacter and Salmonella in poultry gut;

• • Evaluate the effects of bioactive components of BPE on the poultry productivity, feed conversion efficiency and overall health;

• • Compare the microbiological quality of the composts produced from the manure of birds grown in presence or absence of BPE.

In this project, blackberry and blueberry pomace extract is the major element that was tested as a water supplement on poultry growth and the colonization level of Campylobacter and Salmonella in poultry gut. So far, we prepared/extracted 5 lb of each blackberry and blueberry pomace extract powder and stored at 4?C for further use. Pomace extract powder was solubilized in water with 10 % ethanol, mixed at 1:1 ratio and provided to the chicken.

Accomplishments/Milestones

Events and activities of your project over that past year in sequence:

1. 1. March 12 to April 30, 2015: Trial 1 with 80 chicks.

1. 1. June 1 to July 13, 2015: Trial 2 with 80 chicks.

1. 1. July 27, 2015: Presented data from Trial 1 to IAFP 2015.

1. 1. October 6 to November 17, 2015: Trial 3 with 80 chicks.

1. 1. November 18, 2015 to present: Sample processing and data analysis.

In Trial 1, we used 80 chicks, which were divided into 4 groups. Group 1, provided with only tap water; Group 2, provided with 0.1 mg Gallic Acid Equivalent (GAE)/mL BPE in water; Group 3, provided with 0.5 mg GAE/mL BPE in water; and Group 4, provided with 1.0 mg GAE/mL BPE in water. Each week, fecal samples were collected to check bacterial shedding and weights were measured to check growth rate. After 7 weeks, all the chicks were euthanized, cecum were collected to check the colonization of Campylobacter and Salmonella.

Figure 1: Chicks provided with various concentrations (mg GAE/mL) of BPE. Colonization of Campylobacter (A) and Salmonella (B) per gram of chick cecum content. Growth performance of chick (C) when provided with various concentrations of BPE as water supplement.

Results indicated that 0.5 and 1.0 mg GAE/mL of BPE significantly reduced the colonization of two major pathogens, Campylobacter and Salmonella in chick cecum (Figure 1A, 1B). However, these two concentrations (0.5 and 1.0 mg GAE/mL) of BPE reduced the median chick weight compared to the control (Figure 1C). Reduction in chick weight will result in economic loss, hence may not be practical to be used in poultry industry. Interestingly, 0.1 mg GAE/mL BPE increased the median weight of the chicks compared to the chicks provided with only water but this concentration did not show any effect on the colonization of bacterial pathogens. As our target is two-fold, “reduction of environmental risks and improving livestock productivity,” we adopted a novel approach to use the BPE in our following trials. In this approach, the control group was provided with only water while the test group was provided with water supplemented with 0.1 mg GAE/mL BPE; and we increased this treatment concentration to 1.0 mg GAE/mL BPE in water for the last 72 h before euthanization. We are currently analyzing the results from the last two trials.

• Figure 1B
• Figure 1C
• Figure 1A

Impacts and Contributions/Outcomes

Current results from this project show the effectiveness of bioactive phenolic extracts from berry byproducts to reduce pathogenic bacterial colonization in chick gut while promoting the growth in chicks. This indicates, use of this extract as water supplement will result in reduced cross contamination of crops with pathogenic bacteria especially in the organic MCLF where animal manure serve as sole source of fertilizer. Moreover, bioactive berry extracts will work as organic growth promoters just like antibiotic growth promoters used in farm animals. We believe the use of organic and natural antimicrobials, instead of chemicals and antibiotics, will improve the biosecurity of products in the MCLF as well as reduce the environmental and health risks in agriculture. It will reduce the costs related to the administration of antibiotics and chemical growth promoters. In addition, natural or “green” antimicrobials will improve consumer satisfaction.

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