Niel Karrow

Dr. Niel Karrow

Department of Animal Biosciences, University of Guelph, Guelph, ON N1G2W1, Canada

Research Focus & Metrics

Academic Career Length

24Years (2003-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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7 March 2018 in Toxins
Verified
Journal Article
Open access
PDF file
RMRui Ma
Rui Ma
LZLei Zhang
Lei Zhang
MLMeng Liu
Meng Liu
YSYong-Teng Su
Yong-Teng Su
WXWen-Mei Xie
Wen-Mei Xie
Lvhui SunLvhui Sun
Lvhui Sun
The objective of this study was to investigate the individual and combined contamination of aflatoxin B1 (AFB1), zearalenone (ZEN) and deoxynivalenol (DON) in feedstuffs from different Provinces of China between 2016 and 2017. A total of 1569 samples, including 742 feed ingredients and 827 complete pig feed samples, were collected from various regions of China for mycotoxins analysis. The results showed that individual occurrence rates of AFB1, ZEN, and DON were more than 83.3%, 88%, and 74.5%, respectively, in all the tested samples. DON was the most prevalent contaminant, followed by ZEN and AFB1, with the average concentrations ranging from 450.0–4381.5 μg/kg, 2.3–729.2 μg/kg, and 1.3–10.0 μg/kg, respectively. Notable, 38.2%, 10.8%, and 0.6% of complete pig feeds were contaminated with DON, ZEN, and AFB1 over China’s regulatory limits, respectively. Moreover, over 75.0% analyzed samples were co-contaminated with two or three mycotoxins. In conclusion, the current study revealed that the feedstuffs in China were severely contaminated with DON, followed by ZEN and AFB1 during the past two years. These findings highlight the importance of monitoring mycotoxins in livestock feed and implementing feed management and bioremediation strategies to reduce mycotoxin exposure.

8 June 2022 in Journal of Animal Science and Biotechnology
Verified
Journal Article
Open access
PDF file
RXRan Xu
Ran Xu
EKElijah G. Kiarie
Elijah G. Kiarie
AYAlex Yiannikouris
Alex Yiannikouris
Lvhui SunLvhui Sun
Lvhui Sun
NKNiel Karrow
Niel Karrow
Mycotoxins are toxic secondary metabolites produced by filamentous fungi that are commonly detected as natural contaminants in agricultural commodities worldwide. Mycotoxin exposure can lead to mycotoxicosis in both animals and humans when found in animal feeds and food products, and at lower concentrations can affect animal performance by disrupting nutrient digestion, absorption, metabolism, and animal physiology. Thus, mycotoxin contamination of animal feeds represents a significant issue to the livestock industry and is a health threat to food animals. Since prevention of mycotoxin formation is difficult to undertake to avoid contamination, mitigation strategies are needed. This review explores how the mycotoxins aflatoxins, deoxynivalenol, zearalenone, fumonisins and ochratoxin A impose nutritional and metabolic effects on food animals and summarizes mitigation strategies to reduce the risk of mycotoxicity.


1 September 2006 in Journal of Dairy Science
Verified
Journal Article
Closed access
PDF file
BSB.S. Sharma
B.S. Sharma
ILI. Leyva
I. Leyva
Flavio Schramm SchenkelFlavio Schramm Schenkel
Flavio Schramm Schenkel
NKNiel Karrow
Niel Karrow
Mastitis, an inflammatory disease of the mammary gland generally caused by intramammary infections, is the most frequently occurring disease in the North American dairy industry. Reduced milk yield, milk quality, and lactation persistency as well as early culling contribute to the economic losses associated with this disease. During intramammary infections, cells of the innate immune system become activated through pattern recognition receptors that recognize conserved molecular signatures associated with the invading pathogen. The quality, timing, and intensity of the host inflammatory and subsequent immune response determine the fate of this disease. Toll-like receptor 4 (TLR4) is an important pattern recognition receptor that recognizes endotoxins associated with gram-negative bacterial infections. Its role in pathogen recognition and subsequent initiation of the inflammatory and immune response makes it a suitable candidate gene for enhancing disease resistance in Canadian Holsteins. In this study, polymorphisms in the TLR4 gene were identified in the Canadian Holstein bull population. Genotypes and haplotypes were constructed, and their associations with somatic cell score and lactation persistency were determined. Sequencing of selective DNA pools was used to reveal polymorphisms in TLR4. Two DNA pools were constituted based on high and low estimated breeding values for somatic cell scores. A total of 3 single nucleotide polymorphisms (SNP), including 1 SNP in a putative promoter region (P-226) and 2 SNP in exon3 (E3+1656 and E3+2021) of TLR4 were detected. A total of 388 bulls were genotyped for the SNP, haplotypes were reconstructed, and their frequencies were obtained. Polymorphisms in these regions were found to be associated with estimated breeding values for lactation persistency, and somatic cell scores in the Canadian Holstein bull population. The unfavorable alleles at P-226 and E3+1656 were found at a frequency of 40 and 37%, respectively; hence, selection against these alleles is promising in Canadian Holsteins. Selection against the unfavorable allele, T at E3+2021, is limited because of its low frequency (7%). Two frequently occurring haplotypes (GCC and CTC) occurred in 86% of the Canadian Holstein bull population chosen for genotyping. The most frequent haplotype (GCC; 54%) was found to be associated with higher lactation persistency and lower somatic cell scores. The transversion SNP in the putative promoter region (P-226) was in a potential DNA binding site.

16 October 2023 in Antioxidants
Verified
Journal Article
Open access
PDF file
STSophie Tieu
Sophie Tieu
ACArmen Charchoglyan
Armen Charchoglyan
LPLauryn Paulsen
Lauryn Paulsen
LWLauraine (Lauri) Wagter-Lesperance
Lauraine (Lauri) Wagter-Lesperance
USUmesh Kumar Shandilya
Umesh Kumar Shandilya
NKNiel Karrow
Niel Karrow
N-acetylcysteine (NAC), an acetylated derivative of the amino acid L-cysteine, has been widely used as a mucolytic agent and antidote for acetaminophen overdose since the 1960s and the 1980s, respectively. NAC possesses antioxidant, cytoprotective, anti-inflammatory, antimicrobial, and mucolytic properties, making it a promising therapeutic agent for a wide range of diseases in both humans and domesticated animals. Oxidative stress and inflammation play a major role in the onset and progression of all these diseases. NAC’s primary role is to replenish glutathione (GSH) stores, the master antioxidant in all tissues; however, it can also reduce levels of pro-inflammatory tumor necrosis factor-alpha (TNF-∝) and interleukins (IL-6 and IL-1β), inhibit the formation of microbial biofilms and destroy biofilms, and break down disulfide bonds between mucin molecules. Many experimental studies have been conducted on the use of NAC to address a wide range of pathological conditions; however, its effectiveness in clinical trials remains limited and studies often have conflicting results. The purpose of this review is to provide a concise overview of promising NAC usages for the treatment of different human and domestic animal disorders.

1 July 2020 in Food and Chemical Toxicology
Verified
Journal Article
Closed access
MLMeng Liu
Meng Liu
LZLei Zhang
Lei Zhang
XCXiao-Han Chu
Xiao-Han Chu
RMRui Ma
Rui Ma
YWYou-Wei Wang
You-Wei Wang
Lvhui SunLvhui Sun
Lvhui Sun