Alexa Gormley

Ms. Alexa Gormley

orcid

Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

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

Representative Publications

View All Publications
1 April 2024 in Animal Bioscience
Verified
Journal Article
Open access
PDF file
Sung Woo KimSung Woo Kim
Sung Woo Kim
AGAlexa Gormley
Alexa Gormley
KJKi Beom Jang
Ki Beom Jang
MDMarcos Elias Duarte
Marcos Elias Duarte
Global pig production has increased by 140% since the 1960s. The increase in global population, coupled with improving socioeconomic conditions of many countries has led to an increased consumption of meat globally, including pork. To keep up with demand and capitalize on economic opportunities, the countries of China, the United States (US), and the European Union (EU) have become the top 3 pork producers globally. China is of particular interest, as it is the both the largest country in pork production and pig numbers, as well as being the largest importer of pork from other countries. Globally, the efficiency of pork production has improved, in relation to the integration of pig production and the dramatic increase in research efforts in pig nutrition and production. Through integration, large producers can consolidate resources and maximize profits and efficiency. The increased research interest and efforts in pig production have given scientists and producers the opportunity to collaborate to adapt to challenges and identify possible solutions to issues brought on by a volatile global market. Intestinal health (23%), general nutrition and growth (23%), and amino acid nutrition (15%) were the top 3 areas (61%) leading research trends in pig nutrition and production. Major dietary interventions with feed additives evaluated include functional amino acids, feed enzymes, pre-/pro-/post-biotics, and phytobiotics with a common goal to improve the growth efficiency by enhancing nutrient utilization and intestinal health. With increasing global issues with environment, pig producers and the supporting scientists should continue their efforts to improve the production efficiency and to reduce the environmental footprint from pig production.

17 January 2025 in Toxins
Verified
Journal Article
Open access
PDF file
HCHyunjun Choi
Hyunjun Choi
YGYesid Ricardo Garavito
Yesid Ricardo Garavito
AGAlexa Gormley
Alexa Gormley
Sung Woo KimSung Woo Kim
Sung Woo Kim
The objective of this review is to investigate the impacts of aflatoxins, particularly aflatoxin B1 (AFB1), on intestinal microbiota, intestinal health, and growth performance in monogastric animals, primarily chickens and pigs, as well as dietary interventions to mitigate these effects. Aflatoxin B1 contamination in feeds disrupts intestinal microbiota, induces immune responses and oxidative damage, increases antioxidant activity, and impairs jejunal cell viability, barrier function, and morphology in the small intestine. These changes compromise nutrient digestion and reduce growth performance in animals. The negative impact of AFB1 on the % change in average daily gain (ΔADG) of chickens and pigs was estimated based on meta-analysis: ΔADG (%)chicken = −0.13 × AFB1 intake per body weight (ng/g·d) and ΔADG (%)pig = −0.74 × AFB1 intake per body weight (µg/kg·d), indicating that increasing AFB1 contamination linearly reduces the growth of animals. To mitigate the harmful impacts of AFB1, various dietary strategies have been effective. Mycotoxin-detoxifying agents include mycotoxin-adsorbing agents, such as clay and yeast cell wall compounds, binding to AFB1 and mycotoxin-biotransforming agents, such as specific strains of Bacillus subtilis and mycotoxin-degrading enzyme, degrading AFB1 into non-toxic metabolites such as aflatoxin D1. Multiple mycotoxin-detoxifying agents are often combined and used together to improve the intestinal health and growth of chickens and pigs fed AFB1-contaminated feeds. In summary, AFB1 negatively impacts intestinal microbiota, induces immune responses and oxidative stress, disrupts intestinal morphology, and impairs nutrient digestion in the small intestine, leading to reduced growth performance. Supplementing multi-component mycotoxin-detoxifying agents in feeds could effectively adsorb and degrade AFB1 co-contaminated with other mycotoxins prior to its absorption in the small intestine, preventing its negative impacts on the intestinal health and growth performance of chickens and pigs.

23 June 2024 in Animals
Verified
Journal Article
Open access
PDF file
AGAlexa Gormley
Alexa Gormley
KJKi Beom Jang
Ki Beom Jang
YGYesid Ricardo Garavito
Yesid Ricardo Garavito
ZDZixiao Deng
Zixiao Deng
Sung Woo KimSung Woo Kim
Sung Woo Kim
The objectives of this review are to identify the nutritional challenges faced by modern sows and present potential solutions to mitigate excessive maternal tissue loss and reproductive failure as it relates to recent genetic improvements. Current feeding programs have limitations to support the rapid genetic improvements in reproductive performance for modern sows. Since 2012, both litter size at birth and fetal weight have increased by 2.26 pigs per litter and 0.22 kg per piglet, respectively, thereby increasing the nutrient needs for sows during gestation and lactation. Prediction models generated in this review predict that modern sows would need 31% more lysine during gestation when compared with current feeding programs. Physiological challenges facing modern sows are also addressed in this review. High oxidative stress, pelvic organ prolapse, and lameness can directly affect the sow, whereas these physiological challenges can have negative impacts on colostrum and milk quality. In response, there is growing interest in investigating the functional roles of select bioactive compounds as feed additives to mitigate the severity of these challenges. Selenium sources, catechins, and select plant extracts have been utilized to reduce oxidative stress, calcium chloride and phytase have been used to mitigate pelvic organ prolapse and lameness, algae and yeast derivatives have been used to improve colostrum and milk quality, and fiber sources and probiotics have been commonly utilized to improve sow intestinal health. Collectively, this review demonstrates the unique challenges associated with managing the feeding programs for modern sows and the opportunities for revision of the amino acid requirements as well as the use of select bioactive compounds to improve reproductive performance.

26 August 2024 in Biology
Verified
Journal Article
Open access
PDF file
AGAlexa Gormley
Alexa Gormley
YGYesid Ricardo Garavito
Yesid Ricardo Garavito
Sung Woo KimSung Woo Kim
Sung Woo Kim
The objective of this review was to identify the characteristics and functional roles of milk coproducts from human, bovine, and porcine sources and their impacts on the intestinal microbiota and intestinal immunity of suckling and nursery pigs. Modern pig production weans piglets at 3 to 4 weeks of age, which is earlier than pigs would naturally be weaned outside of artificial rearing. As a result, the immature intestines of suckling and nursery pigs face many challenges associated with intestinal dysbiosis, which can be caused by weaning stress or the colonization of the intestines by enteric pathogens. Milk oligosaccharides are found in sow milk and function as a prebiotic in the intestines of pigs as they cannot be degraded by mammalian enzymes and are thus utilized by intestinal microbial populations. The consumption of milk oligosaccharides during suckling and through the nursery phase can provide benefits to young pigs by encouraging the proliferation of beneficial microbial populations, preventing pathogen adhesion to enterocytes, and through directly modulating immune responses. Therefore, this review aims to summarize the specific functional components of milk oligosaccharides from human, bovine, and porcine sources, and identify potential strategies to utilize milk oligosaccharides to benefit young pigs through the suckling and nursery periods.