Opportunistic Grazing is a term used to maximize forage grazed on marginal land for heifer development. Research work completed in Wisconsin nearly a decade ago and recently published defined the differences between heifers reared on pasture for 6 months annually vs those housed in confinement year-round.

Heifer development is the second most expensive portion of the dairy enterprise, and feed going into your replacements is the easiest metric to change. Simply by rotating the females between pastures every 2-4 days during optimum grazing conditions, this data suggests a return of nearly 2700 lbs milk during her first lactation when compared to the ‘couch potato’ counterpart on TMR.

Listen in today to learn about what observations to expect, how to be responsive and nimble to weather while decreasing cost of production. Additionally, researchers Ken Kalscheur and Carlos Camisa Nova provides a sneak peek at future research being conducted to better understand what is changing in the heifer to improve first lactation performance.

Topics of discussion

1:57 Introduction of Dr. Kalscheur and Carlos Camisa Nova 3:07 Project design/details/background 6:30 How was the pasture measured 7:46 Discussion of supplementation strategies 9:04 TMR composition for 1.8 ADG goal 10:03 Bodyweight difference after first grazing season 12:24 Supplementation strategy to bred heifers, during a drought year 14:59 Feed costs – pasture vs TMR, reduction of 35% 17:21 Repro effect of pasture vs confinement 18:59 First lactation performance of pasture based heifer development 20:02 Impact on Dry matter intake during first lactation 22:23 Follow up project, in progress, to assess possible metabolic differences 25:40 Impact of an activity difference in the two styles of rearing animals 27:57 What do you want ‘boots on the ground’ dairymen to know about your project

Featured Article:

Growth and lactation performance from dairy heifers raised in confinement or on pasture

#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #pasture; #replacement; #heiferdevelopment; #milk; #dmi; #active; #dairysciencedigest; #ReaganBluel

The A2 protein variant was identified back in the 60s as a genetic difference among cattle. Recent consumer interest has driven a demand for A2/A2 milk, resulting in increased prevalence in the dairy industry. Acknowledging the importance of protein in cheese production, food scientists have worked with cheese makers to both identify and reduce the impact of A2 on cheese yield.

Beyond yield impacts, Dr. Ibanez and his team of researchers at the Center for Dairy Research wanted to better understand specifically how proteolysis differs when casein proteins change and if this knowledge can ultimately be used to improve the human health impacts of cheese.

Listen in to better understand how one slight change in amino acid sequence can transform the ripening process and ultimately the nutrients in your cheese.

Topics of discussion

1:26 Introduction of Dr. Rodrigo Ibanez 2:32 Different proteins present in milk, based on genetics 4:00 How A2 milk impacts cheese making efficiency 5:52 Description of 4 types of casein in milk protein 8:07 Cheese yield losses with A2 milk ameliorated with skill of cheese makers. 9:46 Art of stirring the curd 10:30 Sire selection for A2, is it moving the mark? 12:10 Experimental design 12:50 How does A2 milk impact cheese quality – gel firmness and ripening 14:14 Protein and Fatty acid impact on flavor 15:50 Description of β-casomorphin peptides 19:11 A2 tend to be a little bit firmer then A1, and slower digestion. 20:20 Opioid activity in cheese 21:00 Testing for A2 protein fractions to confirm A2 milk was used for A2 cheese 22:42 Will aging help all cheeses be easier to digest? β-casomorphin 7 concentrations. 25:04 β-casomorphin impact on human health 26:54 What do you want ‘boots on the ground’ dairymen to know about your project

Featured Articles:

Comparison of the proteolysis and occurrence of a range of β-casomorphin peptides in commercial U.S. Cheddar cheeses manufactured from A1/A2 and A2/A2 β-casein milks

#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #A2; #β-casomorphin; #casein; #A1; #ripening; #cheese; #whey; #DRMS; #dairysciencedigest; #ReaganBluel

The trajectory of the success for a dairy cow begins with mammary development, long before lactation begins. Dr. Benjamin Enger, Associate Professor for The Ohio State University in Wooster, has worked with his team for years to best understand how infection can change the development and if the timing of infection impacts that response.

He was specifically interested in Staphylococcus aureus (SA), a common contagious pathogen in dairy farms. To study this, 21 bred heifers at three stages (6.5, 7.5 and 8.5 months) of pregnancy were inoculated, and tissue samples were collected 21 days later to determine the damage done.

In this edition, there is much discussion about the physiology of mammary gland development and how different stages of pregnancy impacts progress towards lactation. Understanding the development of the mammary, will likely illuminate the importance of seemingly meniscal management steps. Analyzing your farm’s data could hold the key to eliminating what might be the source of this devastating pathogen.

Listen in today to learn more!

Topics of discussion

1:40 Introduction of Dr. Ben Enger 3:08 Project set up 3:47 Knowledge gained in projects leading up to this hypothesis 6:53 What is mammary epithelial cells (MEC) and stromal cells 10:18 How did Staph Aureus (SA) impact amount of MEC and stromal cells in infected quarters 13:21 Cellular changes in heifers 6.5 vs 8.5 months pregnant 17:00 Cellular differences between the edge tissue vs the center (pic p4) 18:40 Duration of impact as the result of SA infection in pregnant heifers 20:54 How does SA get into calves prior to freshening? 22:53 Did you observe immunotolerance in the pregnant heifers? 25:53 What do you want ‘boots on the ground’ dairymen to know about your project 27:26 Experimental increase of milk using blanket therapy to heifers precalving 28:17 Examine first test SCC in first calf heifers 27:20 What do you want ‘boots on the ground’ dairymen to know about your project

Featured Articles:

Impact of Staphylococcus aureus intramammary infection on cellular proliferation and apoptosis on developing mammary glands of pregnant dairy heifers

Supporting article: Impact of intramammary infections on mammary gland development in pregnant dairy heifers during late gestation

#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #SA; #staphaureus ; #SA; #mammary; #mammarydevelopment; #heifer; #milk; #dairysciencedigest; #ReaganBluel