Past Events

Good morning CGIL, We are happy to have with us Dr. Lassen, a Senior Project Manager at VikingGenetics and an Adjunct Associate Professor at Aarhus University, to present this Friday, January 20th, 2023. The seminar will begin at 1:30 PM EDT/EST on the virtual platform Microsoft Teams. The title of the presentation is: "Genetic and management analysis of efficiency and body weight data using 3D measures in commercial farms".

The objectives of this thesis were to 1) evaluate the impact of supplementing omega-3 (n3) fatty acids (FA) using calcium salts enriched in fish oil (Ca-FO) during the early postpartum period on the degree and resolution of inflammation using an induced acute inflammation model, and 2) test whether these effects were from an increased energy density of the diet or were due to the effects of n3 FA on immune cell biology. Supplementing Ca-FO was reflected by changes in the FA composition of plasma, milk, and peripheral blood leukocytes.

Several components of dairy farm rearing systems are known to affect developmental programming of calves by acting as epigenet-ic regulators, influencing the trajectory of immune system development.

Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis (leukosis) and is endemic to the North American dairy cattle population. It is a chronic, contagious disease with no available treatment or vaccine, resulting in lifelong infection. Infection with BLV can lead to persistent lymphocytosis and tumour development within two to five year of infection, and is associated with decreased milk production, immune dysregulation, fertility challenges, and reduced longevity.

The objective of this dissertation was to investigate if dietary supplements could improve dairy calf health and welfare. The first study was focused on investigating the effects of Echinacea purpurea (EP) supplementation on markers of immunity, health, feed intake, and growth of dairy calves. Overall, EP supplementation was associated with blood markers indicative of reduced inflammation and stimulated immunity, with minor benefits to health and growth.

Butyrate is a short-chain fatty acid with considerable benefits to gut health, and in recent years has been commonly used as an alternative to antimicrobials in agricultural animal production. In this thesis, we assessed the protective effects of sodium butyrate (NaB) on larval zebrafish during a lethal Pseudomonas aeruginosa polysaccharide (LPS) challenge and elucidated potential protective mechanisms of action. Larval zebrafish were pre-treated with 3 concen-trations of NaB for 24 hours at 72 hours post fertilization (hpf), and then immune challenged with 60 μg/mL of LPS at 96 hpf.

Poorly developed immune and digestive systems in neonatal chicks impede smooth transition to the production environment and have a significant impact on lifetime biological and economic performance. Integration of breeder nutrition may bolster perinatal immunocompetence and resiliency to production stressors. The work presented in this thesis investigated the impact of dietary sources of omega -3 polyunsaturated fatty acids (n-3 PUFA) in broiler breeders and their progeny.

Laying hens housed in complex housing systems (e.g., aviaries) must be raised in equally complex rearing systems to thrive. Using three-dimensional space requires physical and cognitive spatial skills, and low levels of fearfulness reduce the risk of injury. However, rearing aviaries vary greatly in the space and complexity of their brooding compartments, where chicks are confined for the first few weeks of life.

The object of the study was the assessment of the potential and limitations of predicting beef cattle body weight (BW) using machine learning (ML) models trained on measurements extracted from 2D images. From 51 Angus-cross calves, five linear body measurements were measured and recorded either directly from the cattle or from their images. These measurements were collected weekly from ages two to eight weeks.