Dairy Science Digest

It’s well accepted that management decisions during the first few weeks of life, can impact the long-term trajectory of success. Easy examples of this fact are colostrum management, plane of nutrition and vaccinations just to name a few. One can typically expect an increase in average daily gain, will return in the bulk tank 2 years later.

Research on social housing over the years has shown an increased rate of gain during the milk phase, but hasn’t captured the implications later in life.

First calf heifers transitioning into the milk string tend to be skittish, reluctant to enter the feed alley and fight with the boss cow. Through this transition, her size matters but also her ability to remain resilient in consistently tolerating the social attributes of the milk string.

Dr. Emily Miller-Cushon, and her team of researchers from the University of FL in Gainesville really wanted to measure the impact of housing type on long-term effects, therefore they made the investment to compare individual, paired or group housing to determine if one housing type would dramatically impact her first lactation success.

Listen in today to learn how social housing could improve your profits through increased survival and milk yields through social resilience.

Topics of discussion

1:49      Introduction of Dr. Emily Miller-Cushon

Long-term effects of dairy calf social housing on first lactation survival and milk yield

Much research has focused around the transition period. Recent findings suggest feeding oleic and palmitic fatty acids could aid in improving the energy balance of the cow, but why? Dr. Andres Contreras and his team of researchers conducted benchtop science, studying fat tissue to best understand the mode of action documented in this month’s featured article.

The mitochondria is the powerhouse organelle in the cell which determines the energy status for the cow. If running efficiently, this ‘cellular engine’ will generate a substantial amount of energy, or ATP. However, when operating inefficiently, due likely to damage from oxidative stress, the organelle will generate less energy, resulting in the cow mobilizing more fat stores to fuel milk production.

We all know, if the negative energy balance “spiral” begins – the cow is going to struggle through the transition period which has lasting implications on the entire lactation. Listen in today to learn about how energy production in early lactation could be impacted by your feeding program.

Topics of discussion

1:45      Introduction of Dr. Andres Contreras

6:55       Two possible paths for the mitochondria in the first week of lactation.

Featured Article:

Oleic Acid Supports Mitochondrial Function During Lipolytic and Pro-Oxidant Challenges in Bovine Adipocytes

Day 3 NEFA article: Concentrations of nonesterified fatty acids and glucose in blood of periparturient dairy cows are indicative of pregnancy success at first insemination

Arguably the most important first step in the life of any calf is successful establishment of passive immunity through colostrum management. This key touchpoint ensures easy newborn calf management for weeks in the future and improved pay price for your bull calves.

Colostrum replacers occasionally need fed, for a variety of reasons. Understanding the key details of absorption, allows colostrum replacer manufacturers to optimize their product and therefore your success.

How does dilution impact the absorption of the colostrum replacer, based on the rate of abomasal emptying? Does this impact the calf’s IgG absorption and ultimately success of passive transfer? Listen in to Dr. Alberto Lopez has he describes the results of his recently released research and observations from the field.

Topics of discussion

1:43      Introduction of Dr. Alberto Lopez

Featured Article:

The effect of dilution of colostrum replacer on IgG absorption, abomasal emptying rate, and gastrointestinal permeability in newborn Holstein calves

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

Featured Article:

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

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  

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

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  

Featured Articles:

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

Supporting article:

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

Embryo transfer has become increasingly popular on US dairy farms to rapidly advance the genetic profile of the herd. This month’s feature article looks at the associations between fertility traits on the success of embryo transfer.

Fertility traits such as daughter pregnancy rate (DPR), cow conception rate (CCR) and heifer conception rate (HCR) are consistently classified with low heritability. However, this retrospective study takes a deep dive into the data stored at the Council of Dairy Cattle Breeding (CDCB) to use the statistical power of dairy farmers data. There, the researchers were able to find a clear impact of these traits on the success of an ET program and long term impact on herd fertility.

Because ultimately  … we’re just interested in more calves on the ground, so listen in to better understand how data is improving ET fertility setbacks.

Topics of discussion

1:39      Introduction of Dr. Sophia Ortega  

Featured Articles:

Association of fertility traits with embryo development and pregnancy establishment

Resources:

Sorghum costs less to plant and requires less water to generate productive tonnages. For years, sorghum has been ignored as a dairy forage, because the starch filled berry was nearly impossible to process, limiting the energy available to the cow. To combat this issue a male sterile bmr dwarf variety was developed with no grain head as an opportunity to harvest a nutrient dense, resilient leafy forage.

Researcher Juan Pineiro, Associate Professor & Extension Dairy Specialist at Texas A&M AgriLife Research and Extension Center in Amarillo and his team substituted a portion of corn silage in the TMR with sorghum silage to determine the feasibility of this forage for dairy farms.

The team found an improvement in dry matter intake which resulted in a nearly 8lb increase in milk produced when substituting 25% of the corn silage with headless sorghum silage. To compensate for the decrease in dietary starch, Dr. Pineiro added ground corn into the ration to balance energy.

Additionally, Dr. Pineiro drew our attention to the recent advancements in berry processing for the non-sterile varieties.

“We were able to see 0-1% intact berries remaining with the recently patented processor,” he explained. This unlocks the starch available to the cow and should causes dairymen to consider planting once again.

He cautions hybrid selection, harvest timing and processing are all keys to making this affordable resilient forage to earn a spot in your ration. Sorghum should be given a second look, especially in water limiting – dairy dense regions. Listen-in to this episode for an update in sorghum advancements for your dairy.

Topics of discussion

2:05      Introduction of Dr. Juan Pineiro

32:21     What’s the custom harvesters charging with this new berry processor

Featured Articles:

Effects of partially replacing corn silage with brown midrib male-sterile sorghum silage on intake, digestibility, and milk production in dairy cows

Effects of a novel onboard sorghum kernel processor and height of cut on berry processing score and ruminal in situ starch disappearance of forage sorghum ensiled for 0 and 90 days

Seventy percent of the protein your herd uses for lactation is derived from the microbial population in her rumen. Researchers from UC Davis and Feedworks USA sought to learn more about how different substrates might impact rumen microbial efficiency. They did this with the ultimate goal of increasing the flow of protein available for absorption to help offset feed costs, recognizing protein is the highest cost of the ration, and likely the largest fraction to the cost of production on most dairies.

“We know that efficency of growth in the rumen varies dramatically, nearly 2 fold. Microbes can use 1/3 of their energy for growth or as much as 2/3,” Hackmann described. His lab is using invitro cultures to attempt to determine why this variation exists. “If we can pinpoint cause then we can accomidate and make microbes grow more efficiently and deliver more protein to the ruminant at a lower cost.”

Past models, used in ration formulation software such as CNCPS, claim rumen bacteria perform digestion more efficiently when fed cellulose, over glucose. However, featured work by Dr. Tim Hackmann’s invitro lab suggests a different result. “We found there will be a larger mass of microbes that grow on glucose then cellulose but they also digest more, so the efficiency is not differnet.”

Listen-in to this episode for in interesting dive into the expected changes in the rumen under these conditions. An added bonus banter from Dr. Benjamin Wenner, ruminant nutritionist with FeedWorks USA and co-author on the featured article, about the futuristic concepts possible for ruminant nutrition with mindful investment.

Topics of discussion

1:29      Introduction of Dr. Tim Hackman and Dr. Benjamin Wenner

Mixed rumen bacteria grow with similar efficiency on cellulose and glucose 

DSD 6.12 | Brachytic corn for increased production

The brachytic gene mutation results in corn that is shorter in stature but an improved digestibility profile. Through a reduction in intranode distance, the corn plant reduces indigestible fiber. Dr. Antonio Gallo, PhD ruminant nutritionist from Università Cattolica del Sacro Cuore and his team in Italy recently studied the impact of this gene mutation on the productivity of the dairy herd.

High quality, home grown forages allow dairy producers to maintain the competitive edge. By limiting the purchase of off-farm nutrients, forages possess the ability to advance or hold back a herd. When brachytic corn was fed, they found a yield increase of 3.8 lbs/cow/day. However, the higher producing animals did not consume more.

“This is likely due to a chemotactic effect,” Gallo describes. The team measured changes in the intake pattern which provided insight to future research questions for data to better understand how this phenomenon could have happened.

The quality of corn silage impacts the health and productivity of the dairy cow. Additionally, her intake behavior is impacted by the ration. As more dairy farms move toward robotic systems, maximizing the energy density of the PMR will directly impact productivity, perhaps brachytic corn is most important in these systems.

Listen in to understand how the brachytic corn variety might work in your operation.

Topics of discussion

1:24      Introduction of Dr. Antonio Gallo

Effect of silage from a new brachytic corn hybrid with a high harvest index on feeding behavior and performance of lactating dairy cows