Dairy Science Commons^™

Investigating Health Events In Dairy Cattle, Samantha Blocker

Capstone Projects

This research focuses on identifying the key predictors of mastitis and ketosis in dairy cattle, two common and costly diseases affecting milk production and animal health. The primary objective was to identify significant risk factors and evaluate the predictive performance of modeling approaches.

To analyze these complex relationships, a longitudinal dataset following a large sample of dairy cattle is studying using several advanced methods. Survival analysis techniques, like Kaplan-Meier estimations, help measure how long cows remain free from health issues. The Cox Proportional Hazards (CPH) model complements this approach by identifying risk factors associated with health-related events over time. These …

Potential Of Anogenital Distance As A Genetic Selection Trait In Canadian Holstein, G.R. Dodd, F.S. Schenkel, F. Miglior, T.C. Bruinjé, M. Gobikrushanth, J.E. Carrelli, M. Oba, D.J. Ambrose, C.F. Baes

Dairy Science and Food Science Faculty Publications: 2022 to Present

Maintaining optimal fertility in dairy cattle herds is a global challenge that is typically addressed through the genetic selection of fertility indicator traits. However, many of the traits currently implemented in breeding programs are heavily influenced by environmental factors, resulting in a slow rate of genetic improvement. Anogenital distance (AGD) has recently emerged as a promising fertility indicator trait due to its association with favorable reproductive outcomes and its higher heritability estimates compared with currently evaluated traits. This study aimed to enhance the understanding of AGD's genetic potential by estimating its genetic parameters in Canadian Holsteins, assessing the reliability …

Derivation Of The Maintenance Energy Requirements In Growing Jersey Heifers: Supplementary Table S1, Addison L. Carroll, Michael J. Vandehaar, Paul J. Kononoff

Department of Animal Science: Faculty Publications

Supplemental table for Addison L. Carroll, Michael J. VandeHaar, and Paul J. Kononoff. Derivation of the maintenance energy requirements in growing Jersey heifers. Journal of Dairy Science (2025).

Comparative Study Of Single Imputation Techniques For The Prediction Of Missing Dairy Data, Ahmed M. Gad Prof, Ahmed Abdelhakim Ahmed Mr, Eman Manaa Prof, Basant Shafik Dr, Sakr Mostafa Prof

Business Administration

Dairy farm records are a crucial component of effective livestock business management. Record analysis allows a farm’s owner to make informed decisions. Incomplete records are less useful for data analysis, so it's important to handle missing values correctly. This study compares different imputation methods for handling missing values in a dataset of dairy records comprising 997 records collected from 234 cows between 2012 and 2022. The dataset was screened against records with missing values and then deleted, resulting in 858 observations from 200 animals. There were missing values in two variables, with a missing percentage of 13.9%: days in milk …

The Impact Staphylococcus Aureus Has On Conventional And Organic Dairy Herds In New Hampshire And New York, Jacqueline Rose Holmes

Honors Theses and Capstones

Staphylococcus aureus is a potentially virulent bacterium that causes mastitis in dairy cattle. The toxins produced from S. aureus impact host immunity, damage the mammary gland, and can adapt to cause antimicrobial resistance. It is important to manage both organic and conventional farms correctly by practicing proper hygiene while milking and providing a clean environment. There is a significant increase of S. aureus cases on organic farms compared to conventional, so there may be ways in which organic management and treatment options could be altered to reduce economic loss and animal suffering. The thesis focuses on the involvement S. aureus …

Developing A Ninhydrin Assay To Determine Methionine And Lysine Loss From Rumen Protected Amino Acid Supplements, Ashley K. Miske

Honors Theses and Capstones

No abstract provided.

Effect Of Pulsed Electromagnetic Field Therapy On Milk Quality In Organic Dairy Cows, Kayla A. Young

Honors Theses and Capstones

Organic dairy systems are limited when it comes to the use of antibiotics and pharmaceuticals which creates opportunities to explore alternative treatments to promote cow health. Pulsed electromagnetic field therapy (PEMF), a form of electromagnetic stimulation, promotes various types of healing for both animal and human medicine. Our objective was to explore the effect of PEMF on milk yield and composition in organic dairy cows. Mid-lactation Jersey cows (n = 35) of various parities were randomly assigned to 1 of 3 treatments: 1) control (CON; n = 12); no PEMF, 2) once daily PEMF (PEMF1; n = 12), …

The Effects Of Heat Stress On The Rumination In Lactating Dairy Cows, Kailey Anne Deighan

Honors Theses and Capstones

This study aimed to (1) investigate the association between Temperature-Humidity Index (THI) and rumination activity patterns in lactating dairy cows, and (2) explore the breed-specific impacts of THI on rumination time in Holstein and Jersey cows. The first hypothesis was that higher THI values would be associated with decreased rumination time (RT). The second hypothesis proposed that Holsteins, due to their lower heat tolerance, would experience greater reductions in RT than Jerseys under heat stress. From June 1 to October 1, 2024, daily climatic data were collected in New Hampshire using VisualCrossing to calculate THI. Each day was categorized into …

Fluke Egg Sedimentation Test Procedure, Department Of Primary Industries And Regional Development, Western Australia

Animal production and livestock factsheets

The department’s approved procedure for detecting trematode eggs and the Eimeria leuckarti sedimentation method (FEST) on faecal samples.