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Full-Text Articles in Dairy Science

Liquid Chromatography With Tandem Mass Spectrometry Method Development For The Determination Of Β–Defensins In Bovine Milk, Symone T. Whalin May 2022

Liquid Chromatography With Tandem Mass Spectrometry Method Development For The Determination Of Β–Defensins In Bovine Milk, Symone T. Whalin

Masters Theses & Specialist Projects

Bovine mastitis, caused by a wide array of pathogens, results in a substantial economic loss for the dairy cattle livestock industry. β-defensins are a part of the bovine’s innate immune system and act as the first line of defense against mastitis. Only foundational research has been done on β-defensins’ ability to treat and prevent mastitis. There have been no analytical methods reported in the literature for analyzing β-defensins in bovine milk. This research aims to create an analytical approach to determine β-defensins in bovine milk. It is challenging to determine an analyte in a complex sample matrix, and milk is …


Shortening Sow Restraint Period During Lactation Improves Production And Decreases Hair Cortisol Concentrations In Sows And Their Piglets, L. Morgan, J. Meyer, S. Novak, A. Younis, W.A. Ahmad, T. Raz Jan 2021

Shortening Sow Restraint Period During Lactation Improves Production And Decreases Hair Cortisol Concentrations In Sows And Their Piglets, L. Morgan, J. Meyer, S. Novak, A. Younis, W.A. Ahmad, T. Raz

Elaine Marieb College of Nursing Faculty Publication Series

Food animal welfare is an issue of great concern, as society has a responsibility for animals under human care. Pork is the most consumed meat worldwide, with more than a billion pigs being slaughtered globally every year. Still, in most countries, sows are restrained in farrowing crates throughout lactation. In these crates, sows arc confined with bars to an area that is just slightly larger than their body. Thus, moving and turning around, grooming, or expressing other natural behaviors are typically impossible. In this study, we utilized a simple and practical modification of conventional farrowing crates to designed farrowing pens, …


Nad Metabolism In Male Reproductive Aging, Mirella L. Meyer-Ficca Oct 2020

Nad Metabolism In Male Reproductive Aging, Mirella L. Meyer-Ficca

Funded Research Records

No abstract provided.


Functional Genomics And Immunologic Tools: The Impact Of Viral And Host Genetic Variations On The Outcome Of Zika Virus Infection, Sang-Im Yun, Byung-Hak Song, Jordan C. Frank, Justin G. Julander, Aaron L. Olsen, Irina A. Polejaeva, Christopher J. Davies, Kenneth L. White, Young-Min Lee Aug 2018

Functional Genomics And Immunologic Tools: The Impact Of Viral And Host Genetic Variations On The Outcome Of Zika Virus Infection, Sang-Im Yun, Byung-Hak Song, Jordan C. Frank, Justin G. Julander, Aaron L. Olsen, Irina A. Polejaeva, Christopher J. Davies, Kenneth L. White, Young-Min Lee

Animal, Dairy, and Veterinary Science Faculty Publications

Zika virus (ZIKV) causes no-to-mild symptoms or severe neurological disorders. To investigate the importance of viral and host genetic variations in determining ZIKV infection outcomes, we created three full-length infectious cDNA clones as bacterial artificial chromosomes for each of three spatiotemporally distinct and genetically divergent ZIKVs: MR-766 (Uganda, 1947), P6-740 (Malaysia, 1966), and PRVABC-59 (Puerto Rico, 2015). Using the three molecularly cloned ZIKVs, together with 13 ZIKV region-specific polyclonal antibodies covering nearly the entire viral protein-coding region, we made three conceptual advances: (i) We created a comprehensive genome-wide portrait of ZIKV gene products and their related species, with several previously …


Fetal Demise And Failed Antibody Therapy During Zika Virus Infection Of Pregnant Macaques, Diogo M. Magnani, Thomas F. Rogers, Nicholas J. Maness, Nathan D. Grubaugh, Nathan Beutler, Varian K. Bailey, Lucas Gonzalez-Nieto, Martin J. Gutman, Núria Pedreño-Lopez, Jaclyn M. Kwal, Michael J. Ricciardi, Tereance A. Myers, Justin G. Julander, Rudolf P. Bohm, Margaret H. Gilbert, Faith Schiro, Pyone P. Aye, Robert V. Blair, Mauricio A. Martins, Kathrine P. Falkenstien, Amitinder Kaur, Christine L. Curry, Esper G. Kallas, Ronald C. Desrosiers, Pascal J. Goldschmidt-Clermont, Stephen S. Whitehead, Kristian G. Andersen, Myrna C. Bonaldo, Andrew A. Lackner, Antonito T. Panganiban, Dennis R. Burton, David I. Watkins Apr 2018

Fetal Demise And Failed Antibody Therapy During Zika Virus Infection Of Pregnant Macaques, Diogo M. Magnani, Thomas F. Rogers, Nicholas J. Maness, Nathan D. Grubaugh, Nathan Beutler, Varian K. Bailey, Lucas Gonzalez-Nieto, Martin J. Gutman, Núria Pedreño-Lopez, Jaclyn M. Kwal, Michael J. Ricciardi, Tereance A. Myers, Justin G. Julander, Rudolf P. Bohm, Margaret H. Gilbert, Faith Schiro, Pyone P. Aye, Robert V. Blair, Mauricio A. Martins, Kathrine P. Falkenstien, Amitinder Kaur, Christine L. Curry, Esper G. Kallas, Ronald C. Desrosiers, Pascal J. Goldschmidt-Clermont, Stephen S. Whitehead, Kristian G. Andersen, Myrna C. Bonaldo, Andrew A. Lackner, Antonito T. Panganiban, Dennis R. Burton, David I. Watkins

Animal, Dairy, and Veterinary Science Faculty Publications

Zika virus (ZIKV) infection of pregnant women is associated with pathologic complications of fetal development. Here, we infect pregnant rhesus macaques (Macaca mulatta) with a minimally passaged ZIKV isolate from Rio de Janeiro, where a high rate of fetal development complications was observed. The infection of pregnant macaques with this virus results in maternal viremia, virus crossing into the amniotic fluid (AF), and in utero fetal deaths. We also treated three additional ZIKV-infected pregnant macaques with a cocktail of ZIKV-neutralizing human monoclonal antibodies (nmAbs) at peak viremia. While the nmAbs can be effective in clearing the virus from …


Symptoms And Causes Of Foamy Bloat In Cattle, Zachary Christman Oct 2017

Symptoms And Causes Of Foamy Bloat In Cattle, Zachary Christman

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The bovine stomach normally produces gases such as ammonia, carbon dioxide and methane. However when these gases become trapped in the bovine stomach because of a thick, frothy or foamy liquid it is called bloat. Cattle bloat is a very old condition and goes by many names but is primarily trapped gas within the bovine stomach. Readily digested feedstuff such as highly processed grain diets or an overabundance of fresh immature alfalfa often leads to a vast amount of small particles and carbohydrates in the rumen; this is the major cause of foamy bloat. Severe bloat causes death by suffocation …


Insulin-Dependent Glucose Metabolism In Dairy Cows With Variable Fat Mobilization Around Calving, C. Weber, C. T. Schäff, U. Kautzsch, S. Börner, S. Erdmann, S. Görs, M. Röntgen, H. Sauerwein, R. M. Bruckmaier, C. C. Metges, B. Kuhla, H. M. Hammon Aug 2016

Insulin-Dependent Glucose Metabolism In Dairy Cows With Variable Fat Mobilization Around Calving, C. Weber, C. T. Schäff, U. Kautzsch, S. Börner, S. Erdmann, S. Görs, M. Röntgen, H. Sauerwein, R. M. Bruckmaier, C. C. Metges, B. Kuhla, H. M. Hammon

Physiology Collection

Dairy cows undergo significant metabolic and endocrine changes during the transition from pregnancy to lactation, and impaired insulin action influences nutrient partitioning toward the fetus and the mammary gland. Because impaired insulin action during transition is thought to be related to elevated body condition and body fat mobilization, we hypothesized that over-conditioned cows with excessive body fat mobilization around calving may have impaired insulin metabolism compared with cows with low fat mobilization. Nineteen dairy cows were grouped according to their average concentration of total liver fat (LFC) after calving in low [LLFC; LFC <24% total fat/dry matter (DM); n = 9] and high (HLFC; LFC >24.4% total fat/DM; n = 10) fat-mobilizing …


Trophoblast Major Histocompatibility Complex Class I Expression Is Associated With Immune-Mediated Rejection Of Bovine Fetuses Produced By Cloning, Heloisa M. Rutigliano, Aaron J. Thomas, Amanda Wilhelm, Benjamin R. Sessions, Brady A. Hicks, Donald H. Schlafer, Kenneth L. White, Christopher J. Davies Aug 2016

Trophoblast Major Histocompatibility Complex Class I Expression Is Associated With Immune-Mediated Rejection Of Bovine Fetuses Produced By Cloning, Heloisa M. Rutigliano, Aaron J. Thomas, Amanda Wilhelm, Benjamin R. Sessions, Brady A. Hicks, Donald H. Schlafer, Kenneth L. White, Christopher J. Davies

Animal, Dairy, and Veterinary Science Faculty Publications

Trophoblast cells from bovine somatic cell nuclear transfer (SCNT) conceptuses express major histocompatibility complex class I (MHC-I) proteins early in gestation, and this may be one cause of the significant first-trimester embryonic mortality observed in these pregnancies. MHC-I homozygous-compatible (n = 9), homozygous-incompatible (n = 8), and heterozygous-incompatible (n = 5) SCNT pregnancies were established. The control group consisted of eight pregnancies produced by artificial insemination. Uterine and placental samples were collected on Day 35 ± 1 of pregnancy, and expression of MHC-I, leukocyte markers, and cytokines were examined by immunohistochemistry. Trophoblast cells from all SCNT pregnancies expressed MHC-I, while …


Analysis Of Johne's Disease Elisa Status And Associated Performance Parameters In Irish Dairy Cows, A. E. Kennedy, N. Byrne, A. B. Garcia, Jim O'Mahony, R. G. Sayers Mar 2016

Analysis Of Johne's Disease Elisa Status And Associated Performance Parameters In Irish Dairy Cows, A. E. Kennedy, N. Byrne, A. B. Garcia, Jim O'Mahony, R. G. Sayers

Department of Biological Sciences Publications

Background

Infection with Mycobacterium avium subspecies paratuberculosis (MAP) has been associated with reductions in milk production in dairy cows and sub optimal fertility. The aim of this study was to highlight the production losses associated with testing MAP ELISA positive in Irish dairy cows. Secondary objectives included investigation of risk factors associated with testing MAP ELISA positive. A survey of management practices on study farms was also conducted, with examination of associations between management practices and herd MAP status.

Blood samples were collected from 4188 breeding animals on 22 farms. Samples were ELISA tested using the ID Screen Paratuberculosis Indirect …


Circulating Amino Acids In Blood Plasma During The Peripartal Period In Dairy Cows With Different Liver Functionality Index, Z. Zhou, J. J. Loor, F. Piccioli-Cappelli, F. Librandi, G. E. Lobley, E. Trevisi Mar 2016

Circulating Amino Acids In Blood Plasma During The Peripartal Period In Dairy Cows With Different Liver Functionality Index, Z. Zhou, J. J. Loor, F. Piccioli-Cappelli, F. Librandi, G. E. Lobley, E. Trevisi

Physiology Collection

The liver functionality index (LFI) measures the changes of albumin, cholesterol, and bilirubin concentrations between 3 and 28 d postpartum. This composite index, based on variables with direct relevance to liver-specific plasma protein synthesis (albumin), hepatic/intestinal lipoprotein synthesis (cholesterol), and clearance of breakdown products of heme catabolism (bilirubin), provides a tool for evaluating manifestations of hepatic disease. Both energy and protein metabolism are likely to be affected by various physiological challenges in this period but have not been tested systematically. The present study was conducted to profile AA in cows with high or low LFI during the peripartal period …


Evaluation Of Calving Indicators Measured By Automated Monitoring Devices To Predict The Onset Of Calving In Holstein Dairy Cows, V. Ouellet, E. Vasseur, W. Heuwieser, O. Burfeind, X. Maldague, É. Charbonneau Feb 2016

Evaluation Of Calving Indicators Measured By Automated Monitoring Devices To Predict The Onset Of Calving In Holstein Dairy Cows, V. Ouellet, E. Vasseur, W. Heuwieser, O. Burfeind, X. Maldague, É. Charbonneau

Physiology Collection

Dystocias are common in dairy cows and often adversely affect production, reproduction, animal welfare, labor, and economics within the dairy industry. An automated device that accurately predicts the onset of calving could potentially minimize the effect of dystocias by enabling producers to intervene early. Although many well-documented indicators can detect the imminence of calving, research is limited on their effectiveness to predict calving when measured by automated devices. The objective of this experiment was to determine if a decrease in vaginal temperature (VT), rumination (RT), and lying time (LT), or an increase in lying bouts (LB), as measured by …


Body Condition Score And Plane Of Nutrition Prepartum Affect Adipose Tissue Transcriptome Regulators Of Metabolism And Inflammation In Grazing Dairy Cows During The Transition Period, M. Vailati-Riboni, M. Kanwal, O. Bulgari, S. Meier, N. V. Priest, C. R. Burke, J. K. Kay, S. Mcdougall, M. D. Mitchell, C. G. Walker, M. Crookenden, A. Heiser, J. R. Roche, J. J. Loor Jan 2016

Body Condition Score And Plane Of Nutrition Prepartum Affect Adipose Tissue Transcriptome Regulators Of Metabolism And Inflammation In Grazing Dairy Cows During The Transition Period, M. Vailati-Riboni, M. Kanwal, O. Bulgari, S. Meier, N. V. Priest, C. R. Burke, J. K. Kay, S. Mcdougall, M. D. Mitchell, C. G. Walker, M. Crookenden, A. Heiser, J. R. Roche, J. J. Loor

Physiology Collection

Recent studies demonstrating a higher incidence of metabolic disorders after calving have challenged the management practice of increasing dietary energy density during the last ~3 wk prepartum. Despite our knowledge at the whole-animal level, the tissue-level mechanisms that are altered in response to feeding management prepartum remain unclear. Our hypothesis was that prepartum body condition score (BCS), in combination with feeding management, plays a central role in the peripartum changes associated with energy balance and inflammatory state. Twenty-eight mid-lactation grazing dairy cows of mixed age and breed were randomly allocated to 1 of 4 treatment groups in a 2 × …


Dry Period Plane Of Energy: Effects On Glucose Tolerance In Transition Dairy Cows, S. Mann, F. A. Leal Yepes, M. Duplessis, J. J. Wakshlag, T. R. Overton, B. P. Cummings, D. V. Nydam Jan 2016

Dry Period Plane Of Energy: Effects On Glucose Tolerance In Transition Dairy Cows, S. Mann, F. A. Leal Yepes, M. Duplessis, J. J. Wakshlag, T. R. Overton, B. P. Cummings, D. V. Nydam

Physiology Collection

Overfeeding energy in the dry period can affect glucose metabolism and the energy balance of transition dairy cows with potential detrimental effects on the ability to successfully adapt to early lactation. The objectives of this study were to investigate the effect of different dry cow feeding strategies on glucose tolerance and on resting concentrations of blood glucose, glucagon, insulin, nonesterified fatty acids (NEFA), and β-hydroxybutyrate (BHB) in the peripartum period. Cows entering second or greater lactation were enrolled at dry-off (57 d before expected parturition) into 1 of 3 treatment groups following a randomized block design: cows …


Nebraska Bqa: Antibiotic Use Guidelines, Rob Eirich Jan 2014

Nebraska Bqa: Antibiotic Use Guidelines, Rob Eirich

Nebraska Beef Quality Assurance Program

Cattlemen have demonstrated a commitment to animal health through vaccination programs developed carefully in cooperation with their veterinarian. When animals must be treated with an antibiotic after disease diagnosis, producers need to follow important antibiotic use guidelines established through the National Beef Quality Assurance (BQA) program.


Nebraska Bqa: Effective Cattle Handling, Rob Eirich Jan 2014

Nebraska Bqa: Effective Cattle Handling, Rob Eirich

Nebraska Beef Quality Assurance Program

Cattlemen know the importance of proper cattle handling and its effect on animal health and performance. Beef Quality Assurance has been implementing effective cattle handling (low-stress) into educational programs since its establishment in the 1980s.


Handling Cattle Through High Heat Humidity Indexes, Rob Eirich Jan 2014

Handling Cattle Through High Heat Humidity Indexes, Rob Eirich

Nebraska Beef Quality Assurance Program

As cattlemen enter the summer months, they need to understand and deal with heat and humidity. Consider incorporating the following practices into management plans to help reduce additional stress.


Nebraska Bqa: Handling Compromised Animals, Rob Eirich Jan 2014

Nebraska Bqa: Handling Compromised Animals, Rob Eirich

Nebraska Beef Quality Assurance Program

Cattle producers have long recognized the need of proper husbandry and stewardship for the animals entrusted into their care. Best livestock production practices, based on research and sound science, help ensure the well-being, animal health and productivity of cattle.


Calf Branding/Processing Time And Beef Quality Assurance, Rob Eirich Jan 2014

Calf Branding/Processing Time And Beef Quality Assurance, Rob Eirich

Nebraska Beef Quality Assurance Program

It is spring and that means branding time across cattle country. As producers are finishing calving season and preparing for branding/processing, it is important to review Beef Quality Assurance (BQA) guidelines. Let's take a minute to look at the key BQA principles:


Audits And Assessments In Beef Cattle Production, Rob Eirich Jan 2014

Audits And Assessments In Beef Cattle Production, Rob Eirich

Nebraska Beef Quality Assurance Program

Assessments and audits are becoming a part of doing business in beef cattle production, as we are seeing beef processors implementing third-party audits. Since beginning as the Nebraska Director of Beef Quality Assurance (BQA) in July, I have been studying and gathering information on the National Cattlemen's Beef Association (NCBA) Assessment Guides and third-party audits in the beef industry.


Nebraska Beef Quality Assurance: Focused On The Safety, Wholesomeness And Quality Of Beef Jan 2014

Nebraska Beef Quality Assurance: Focused On The Safety, Wholesomeness And Quality Of Beef

Nebraska Beef Quality Assurance Program

Across the nation, beef producers face the challenge of making a living from the land, while producing safe, wholesome beef. Beef that will provide a great eating experience each and every time for American and International consumers.


Nebraska Bqa: Herd Health Plan/Protocol, Rob Eirich Jan 2013

Nebraska Bqa: Herd Health Plan/Protocol, Rob Eirich

Nebraska Beef Quality Assurance Program

Nebraska cattlemen have demonstrated a commitment to the integrity of today's beef products by implementing sound cattle management practices. Consumers are looking for beef raised in a healthy and safe environment. An appropriate Herd Health Plan/Protocol ensures that all cattle are raised in the best health.


Nebraska Bqa: Veterinarian Client Patient Relationship, Rob Eirich Jan 2013

Nebraska Bqa: Veterinarian Client Patient Relationship, Rob Eirich

Nebraska Beef Quality Assurance Program

Beef producers are committed producing a high quality, safe and wholesome beef product. A commitment to herd health and veterinary input is critical to achieving this goal. To this end, developing a veterinarian client-patient relationship (VCPR) is important and will benefit all aspects of cattle performance. Veterinarians' working understanding of cattle disease and parasites can help cattle raisers develop targeted vaccination and treatment programs.


Mammary Cell Activity And Turnover In Dairy Cows Treated With The Prolactin-Release Inhibitor Quinagolide And Milked Once Daily, M. Boutinaud, V. Lollivier, L. Finot, R. M. Bruckmaier, P. Lacasse Jan 2012

Mammary Cell Activity And Turnover In Dairy Cows Treated With The Prolactin-Release Inhibitor Quinagolide And Milked Once Daily, M. Boutinaud, V. Lollivier, L. Finot, R. M. Bruckmaier, P. Lacasse

Physiology Collection

To assess the regulation of mammary cell activity, survival, and proliferation by prolactin (PRL), 5 Holstein cows in early lactation received daily i.m. injections of 1 mg of quinagolide, a suppressor of PRL release, for 9 wk, whereas 4 control cows received the vehicle (water) only. During the last week of treatment, one udder half was milked once a day (1×) and the other twice a day (2×). Mammary biopsies were harvested 1 wk before and 4 and 8 wk after the start of quinagolide treatment. The quinagolide injections reduced milk yield and resulted in lower levels of κ-casein and …


Caring For Compromised Cattle: Assessing Animals At Risk Jan 2011

Caring For Compromised Cattle: Assessing Animals At Risk

Nebraska Beef Quality Assurance Program

Cattlemen have long recognized the need to properly care for their livestock. Sound animal husbandry practices – based on research and decades of practical experience – are known to impact the well-being of cattle, individual animal health and herd productivity. There is no doubt that producers work hard to ensure that their cattle are properly cared for throughout all stages of production. Unfortunately, it’s a fact of raising cattle that some animals will become injured to the extent that they are unable to stand or walk without assistance.


Assessor’S Guide To A Beef Quality Assurance Cow-Calf Assessment Jan 2011

Assessor’S Guide To A Beef Quality Assurance Cow-Calf Assessment

Nebraska Beef Quality Assurance Program

The BQA Cow-Calf Assessment is an on-site educational tool that allows for assessing and benchmarking key indicators of animal care and well-being as well as operational conditions. The Cow-Calf Assessment focuses on three main areas – Animals, Records and Best Management Practices (BMP), and Facilities and Equipment.


Dairy Animal Care: Quality Assurance Jan 2010

Dairy Animal Care: Quality Assurance

Nebraska Beef Quality Assurance Program

Dairy producers are encouraged to participate in the voluntary Dairy Animal Care and Quality Assurance (DACQA) Certification program. The purpose of this program is to enhance and demonstrate quality animal care practices, which assure food safety, quality and value as well as enhance consumer confidence in the milk and beef products that are harvested from cattle on America’s dairy farms.


Development Of A New Tacaribearenavirus Infection Model And Its Use To Explore Antiviral Activity Of A Novelaristeromycin Analog, Brian B. Gowen, M. H. Wong, D. Larson, W. Ye, K. H. Jung, E. J. Sefing, Ramona T. Skirpstunas, Donald F. Smee, John D. Morrey, S. W. Schneller Jan 2010

Development Of A New Tacaribearenavirus Infection Model And Its Use To Explore Antiviral Activity Of A Novelaristeromycin Analog, Brian B. Gowen, M. H. Wong, D. Larson, W. Ye, K. H. Jung, E. J. Sefing, Ramona T. Skirpstunas, Donald F. Smee, John D. Morrey, S. W. Schneller

Animal, Dairy, and Veterinary Science Faculty Publications

Background

A growing number of arenaviruses can cause a devastating viral hemorrhagic fever (VHF) syndrome. They pose a public health threat as emerging viruses and because of their potential use as bioterror agents. All of the highly pathogenic New World arenaviruses (NWA) phylogenetically segregate into clade B and require maximum biosafety containment facilities for their study. Tacaribe virus (TCRV) is a nonpathogenic member of clade B that is closely related to the VHF arenaviruses at the amino acid level. Despite this relatedness, TCRV lacks the ability to antagonize the host interferon (IFN) response, which likely contributes to its inability to …


Feedyard Assessment: Assessor's Guide Jan 2009

Feedyard Assessment: Assessor's Guide

Nebraska Beef Quality Assurance Program

The BQA Feedyard Assessment is an on-site educational tool that allows for assessing and benchmarking key indicators of animal care and well-being as well as feedyard conditions. The Feedyard Assessment focuses on three main areas – Animals, Records and Best Management Practices (BMP), and Facilities and Equipment.


Stocker And Backgrounding Self Assessment Jan 2009

Stocker And Backgrounding Self Assessment

Nebraska Beef Quality Assurance Program

Cattlemen in stocker operations have long recognized the need to properly care for livestock. Sound animal husbandry practices, based on decades of practical experience and research, are known to impact the well-being of stocker cattle, individual animal health and herd productivity. Stocker cattle operations are located in many diverse environments and geographic locations in the United States. A universal set of production practices can not be recommended for all stocker cattle producers in light of the divergent climate and geographic variations of the stocker and backgrounding segment. Personal experience, training and professional judgment can serve as a valuable resource for …


Got Controversy - Milk Does, Margaret Sova Mccabe Oct 2008

Got Controversy - Milk Does, Margaret Sova Mccabe

Law Faculty Scholarship

This article analyzes ongoing controversy over how to best label rBST-free milk. Recombinant bovine somatotropin is a genetically engineered drug administered by some farmers to their dairy herds to increase milk production. FDA first approved its use in 1994, despite great controversy. The FDA also issued labeling guidelines that allowed voluntary disclosure of rBST-free milk, so long as it carried the disclaimer that no difference could be detected between milk produced with rBST and rBST-free. The controversy continues today as consumers express a preference for rBST-free milk and many rBST-free producers label their milk this way. "Conventional" milk (with rBST) …