Dairy Science Digest

DSD 5.11 | Subtle Sync changes to synergize estrus with ovulation

Reproductive physiologists are always trying to improve conception rates for the dairy herd. Double ovsync is one of the best tools in our toolbox to submit cows to first insemination. However, as estrus detection technology becomes more affordable and we learn more about physiology, perhaps combining the expression of estrus at insemination may improve fertility through optimizing ovulation timing.
Dr. Julio Giordano and Ana Laplacette worked with their Cornell reproduction team to investigate this theory on over 4600 cows in 2 commercial herds. “We are trying to take advantage of the power of sync of ovulation and the power of estrus” Giordano explains. “To get the best of both, synergize the two.”
The only change to the well-known Double ovsync protocol includes a delay in the final administration of GnRh before breeding. The goal, allowing the cows more time to show estrus. Take a moment to listen in to better understand the physiology of this synchronization program and how to improve your herd’s reproductive management.  
Topics of discussion
2:03       Introduction of Dr. Julio Giordano & Ana Laplacette3:37       Why introduce Estrus detection to double ovsync? 6:25       Treatment description, Double ovsync9:12       Did you cherry pick? 10:04     What metrics do you focus in on to determine the success of synchronization protocol11:36     Considerations to grouping animals to best understand the data 13:57     How did you determine “heat” 15:23     Specific difference between G56 and G80 treatments 16:38   Increase in Estrus observed 2.2% vs 29.9% 17:09     Three types of cows –                (1) Show estrus without GnRh, 1/3               (2) Show estrus after GnRh, 1/3               (3) Never show estrus, 1/3  20:01     Anestrus cows – table 5 22:16     Follicle size differences between treatment26:12     Did it work? Take home message for boots on the ground dairy producers 30:41     What is the difference between the estrus and non-estrus cows? 32:16     Follow up project: Give cows 1 week to show estrus after PGH of breeding OvSync
Featured Article:
Delaying induction of ovulation and timed AI in a Double-Ovsynch protocol increased expression of estrus and altered first service reproductive outcomes of lactating dairy cows
 
#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #DoubleOvSync; #G56; #G80; #cherrypick; #sync; #estrus; #dairy; #Lut; #GnRH; #conceptionrate; #dairysciencedigest; #ReaganBluel; 

DSD 5.10 | Rumen friendly fatty acids in High Oleic Beans

DSD 5.10 | Rumen friendly fatty acids in High Oleic Beans
Soybeans and dairy cows have walked hand for decades. These oil beans are known specifically for the amino acid sequence in their high-quality protein and energy to support lactation. Recent developments in plant breeding has shifted the fat profile of the bean contain a higher amount of Oleic fat, which is easier for the rumen to digest, in certain varieties.  Substituting linoleic acid for higher concentrations of oleic allows nutritionists to increase the inclusion rate in the diet and therefore support the herd during times of high production. This month we feature an article from  Dr. Adam Lock and his team at Michigan State University as highlighting research generated from on-farm questions.
Ensuring producers know how much to feed, and how to feed high oleic soybeans to the herd was the objective of a series of research projects in the pipeline of publications due to come from MSU in the coming months and years. Listen in to here if growing this new variety of bean makes sense for your operation.
Topics of discussion
1:56       Introduction of Adam Lock  3:37       What’s the difference between conventional beans and HOSB?7:41       Raw vs Roasted10:38     Research Treatments, 4 rations 12:28     Table 2 – Statistical Contrasts13:24     ECM impacts 16:48     Sourcing HOSB18:45     Future research questions19:34     Palmitic acid for milk fat improvements 21:03     Upcoming transition cow research 22:43     HOSB impacts on metabolism – research in works24:10     DMI/ECM25:03     Take home message for boots on the ground dairy producers27:28   On-Farm Roasting
Featured Article:
Effects of raw and roasted high oleic soybeans on milk production of high-producing dairy cows
 
Supporting Article:
Effects of increasing dietary inclusion of high oleic acid soybeans on milk production of high-producing dairy cows
 
 
 
 
 
 
#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #HighOleic ; #soybean; #Plenish; #soyleic; #HOSB; #ration; #dairy; #rumen; #FA; #oleic; #dairysciencedigest; #ReaganBluel; 

DSD 5.9 | Undegradable NDF clogging your herd?

Despite decades of dedicated research, the rumen still remains a bit of a ‘black box’. This month we feature an article from  Dr. Gonzalo Ferreira and his team at Virginia Tech as they try further define how undegradable fiber impacts the rumen's flow rate, and therefore productivity.
Comprehending the kinetics of degradation will assist in identifying the ideal combination of ingredients to create a profitable ration for your herd.
Could this help you make future planting decisions, as the nation is repairing from several rounds of drought? Does the ‘queen of forages’ belong in your cropping program?
Listen in to learn more!
Topics of discussion
1:48       Introduction of Dr. Gonzalo Ferreira 3:33       Impact of Fiber in the ration4:15       Compare Alfalfa to temperate grasses 5:16       Segregating Fiber, pdNDF vs uNDF8:04       Design of research rations 9:23       Feeding grasses to lactating dairy cows 12:40     Main variable of interest, ruminal passage rate 13:34     Dry matter intake 16:03    Ration strategy around flow rates and rumen pool size 19:08     Forage sample analysis selection 21:21     Cost of the rations23:32     Plant more Alfalfa or Orchard Grass? 26:36     Take home message for boots on the ground dairy producers
Featured Article:
Ruminal passage rate and digestibility of fiber from dairy cows consuming diets containing alfalfa and orchardgrass hays with different concentrations of undegradable neutral detergent fiber (uNDF)
#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #queenofforages; #Alfalfa; #NDF; #uNDF; #pdNDF; #orchardgrass; #ration; #kinetics; #dairy; #rumen; #dairysciencedigest; #ReaganBluel; 

DSD 5.8 | Magnesium matters

Seems like calcium and phosphorus gather up all the attention, but there is growing awareness of the importance of magnesium – the “runner up mineral” in the dairy cow diet. Some sources of magnesium are simply more available than others. This fact has the ignited the interest of ruminant nutritionists looking to focus their research efforts on determining the most available Mg source so you can get the biggest bang for your buck.
This month we featured an article from Dr. Noelia Silva Del Rio, from UC Davis. She describes her research on the rumen availability of different popular magnesium sources and explains the importance of magnesium and how to improve the mineral status of your herd. Listen in to learn more!
Topics of discussion
1:32       Introduction of Dr. Noelia Silva 3:28       How does vitamin D impact mineral absorption? 3:42       Regulation of bone mineral mobilization 3:55       relationship of Mg normalizing blood vitamin D4:53       Human mineral deficiencies 6:21       5 forms of Mg researched:               Most soluble, most common and a proprietary blend 7:57       Bolus vs pre-mix8:51       How magnesium is absorbed in the cow9:42       Solubility trial: popular is not the same as available 12:18     Why were open, non-lactating dairy cows tested? 13:11     Urine results over 24 hour15:22     MgS most available (Figure 2)16:27     Adjust for pre-treatment Mg excretion (Figure 3) 18:09     Recommendations for Nutritionists20:17     Quick field test for Mg availability 20:57     Take home message for boots on the ground dairy producers
Featured Article: Relative availability of 5 inorganic magnesium sources in non-pregnant, non-lactating Holstein cows.
Additional Information:Dr. Goff’s field test - https://www.dairyherd.com/news-news-news/magnesium-most-critical-mineralRecommended mineral paper for producers: https://avmajournals.avma.org/view/journals/javma/222/11/javma.2003.222.1518.xml
 
#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #Magnesium; #Mg; #Ca; #P; #mineral; #dairy; #hypocalcemia; #dairysciencedigest; #ReaganBluel; 

DSD 5.7 |Machine learning to find SARA prevalence in your herd

Subacute Ruminal acidosis, commonly referred to as SARA, could be robbing your herd of production. When pH dips too low for too long the biology of the rumen shifts, butterfat slides and overall health of the herd is negatively impacted.
But how can you tell if your herd has SARA?
This month we invite Dr. Eric Paquet and Felix Huot, from Université Laval in Quebec Canada to explain the method of using DHI milk samples to map the prevalence of SARA in the dairy herd of Quebec.
Listen in to learn more - 
Topics of discussion
1:48       Introduction of Dr. Eric Paquet and Felix Huot 2:55       What is SARA – how is it defined what are the symptoms?  4:42        Pair Feeding – Intake experimental design5:10       Rumen Bolus for research monitoring for calibration6:57        Rumen pH for definition of SARA7:40        7 commercial herds for phase 1 calibration 10:35     Ruminal Biochemistry changed by SARA13:08     Ruminal variability among cows within the same herd14:54     Phase 2: applied statistical model to a dataset of 3000 farms in Quebec to predict prevalence 17:24     Mean, range (min-max) prevalence of SARA18:35     Factors associated with an increase prevalence of SARA19:27     Robotic herds20:50     Seasonal effect 21:40     Higher milk yield 22:05     Take home message for boots on the ground dairy producers
Featured Article:
Featured Article: Predicting subacute ruminal acidosis from milk mid-infrared estimated fatty acids and machine learning on Canadian commercial dairy herds
Background Information:Relationship between farm management strategies, reticuloruminal pH variations, and risks of subacute ruminal acidosis
 
 
#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #SARA; #machinelearning; #VFA; #milk; #fattyacid; #acidosis; #FA; #dairysciencedigest; #ReaganBluel; 
 

DSD 5.6 | Heat stress changes to the Mammary Gland

When your bulk tank volume takes a plunge through the last bout of heat, do you ever wonder exactly WHY? What is it in the udder that changes to cause the decline? Why do we also commonly see elevated SCC in our tanks too?
To best understand the why, the Virgina Tech dairy team collected tissue samples from the mammary gland of cows in controlled environmental chambers. This month we invite Dr. Ben Corl to explain the cellular changes observed in the alveoli, epithelial and even immune cells of the mammary gland of cows undergoing a controlled heat stress challenge.  
Additionally, he’ll describe the changes in gene expression in those same tissue samples that controls protein production and mammary health.
This continuation of our heat stress series features two papers titled: (1) Cyclical heat stress during lactation influences the microstructure of the bovine mammary gland(2) 2022: Heat stress increases mammary epithelial cells and reduces viable immune cells in milk of dairy cows
Topics of discussion
1:28       Introduction of Dr. Ben Corl2:36       Describe the experimental design 3:58        Pair Feeding – Intake experimental design7:14        Could the cows cool during the evening ? 8:47        Microscopic changes to the mammary 10:31     Cellular turnover in the alveoli  13:20     Increased losses of epithelial cells, a portion of the somatic cell population 16:39     Decline in viable Immune cell population in the mammary 19:38     Body temperature before and after milking 20:16     Number of alveoli24:07     Gene & protein expression changes 24:56     Gene expression pathway for cellular health in the mammary26:25     What do you want Boots on the ground dairyman to know
Background Information:Temperature Humidity Index (THI)
#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #heatstress; #alveoli; #milk; #mammarydevelopment; #mammary; #dairysciencedigest; #ReaganBluel;
 

DSD 5.5 | Avoid generations of production losses

Florida researchers began a generational study in 2007 that is still years in the making. It all began with the investigation of the impact of heat stress on dry cows to measure changes that might occur to the calf incubating inside the hot dam, like a crock pot.
In addition to seeing negative production impacts on mama, the researchers began to measure numerous changes in the damaged calf coming out of the heat stressed dry cow. This month’s edition, we’ll be interviewing Dr. Jimena Laporta, of the University of Wisconsin, to better understand the physiological changes of the calf that results in lost production for her entire life. She and her team measured changes in mammary and adrenal gland development.
Several separate papers have been peer reviewed over the 17 years of research. Many are linked at the bottom of the show notes for additional reference.
Listen in to understand how heat stressed dry cows can destroy your favorite cow families’ production records.
This month features two released paper titled: (1) Carry-over effects of maternal late-gestation heat stress on granddaughter’s growth and mammary gland development (ck out histology – Fig 1&2) (2) Programming effects of intrauterine hyperthermia on adrenal gland development
Topics of discussion
1:58       Introduction of Dr. Jimena Laporta4:17       Describe the experimental design 6:19        Description of the generations impacted through in utero heat stress 7:29        The biological link between the grand dam and the grand daughter (F2) 9:16        Eight years of research to collect multigenerational data 10:39     F1 management in WI beginning at 8 weeks12:00     F1 mammary implications following heat stress while developing in utero 13:32     F2 calves – changes as a result of dam’s exposure to heat stress while developing in utero15:01     Early mammary growth 15:32     What is causing these differences in F217:35     Lumen space and estrogen receptors 19:06     Summary of 3 generations of damage    20:34     Should I build a lactating barn or dry cow barn? 22:39     The Adrenal Gland 27:38     Adrenal effect on inflammation28:56     What do you want Boots on the ground dairyman to know
Background Information:Temperature Humidity Index (THI)2020 Dairy Science Digest Podcast interview 2020: Late-gestation heat stress impairs daughter and granddaughter lifetime performance (economic impact)2016: In utero heat stress decreases calf survival and performance through the first lactation
#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #heatstress; #fetalprogramming; #F1; #milk; #adrenal; #mammarydevelopment; #mammary; #dairysciencedigest; #ReaganBluel;

DSD 5.4 | Reconsider Choline for lasting returns

Choline, a pseudovitamin, is required by all mammals including the dairy cow for many essential functions. Research in supplementing rumen protected choline really took off about twenty years ago, however continues today to best understand how this feed through additive can positively influence profitability. Dr. Usman Arshad joins the conversation for this episode to highlight his comprehensive summary of all the peer reviewed, published research completed on Choline. Listen in to best understand the assumed mode of action choline uses to help provide an improved efficiency in milk production for the majority of the lactation, even when only fed during the 42-day transition period.
The findings we discuss are published in the recently released paper titled: Exploring choline's important roles as a nutrient for transition dairy cows
Topics of discussion
1:19       Introduction of Dr. Usman Arshad2:17       What is Choline?3:45       Phospholipid production – choline’s role6:15       How does choline impacts the transition Cow7:46       Fatty acid impact on the Liver 8:39       Major factor choline plays on fatty acid transport 13:16    Twenty year average Milk Response when feeding choline for 42 days (-21 to 21 dim)15:47    Milk Response when feeding choline – more current average from 2020-202417:18    Mode of action, intestinal lining?20:02    Additional possible modes of action21:47    Choline as a treatment for fatty liver 23:24    Choline results in elevated milk yield, regardless of body condition score 26:16    Inflammation through in early lactation 27:29    Energy cost of bacterial infection30:30    What’s the one take home message for boots on the ground dairymen31:35    Return on investment calculations
Featured article: Exploring choline's important roles as a nutrient for transition dairy cows
#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #Choline; #transition; #transitiondairy; #vitamin; #fattyacid; #negativeenergybalance; #TMR; #dairysciencedigest; #ReaganBluel;

DSD 5.3 | Slight modifications of CIDR Sync - help or hinder?

DSD 5.3 | Slight modifications of CIDR Sync - help or hinder?
In this time of heifer inventory shortage – getting heifers pregnant (in a timely fashion) is even more important than ever.
Contract heifer growers in California sought the help of Dr. Fabio Lima and his team at UC Davis to best understand the use of a 6-day CIDR sync with variable rates of GnRH could increase pregnancies when bred to sexed semen.
The findings we discuss are published in the recently released Journal of Dairy Science article titled: Effect of 200 μg of gonadorelin hydrochloride at the first GnRH of a CIDR Synch program on  ovulation rate and pregnancies per AI in Holstein heifers.
Listen in to hear the results and nuanced details of controlling reproductive structures using timed AI protocols.
Topics of discussion
1:03       Production costs of heifer rearing - survey results 2:09       Introduction of Dr. Fabio Lima 3:46       Description of the project 4:20       TAI protocol description5:31       Varying GnRH dose6:34       What is the function of GnRH in the heifer? 7:51       Hallmark of a successful synchronization 8:24       Results of ultrasound (ovulation) and P4 blood sample analysis 10:04    Did increased ovulation translate into improved pregnancy outcome? 10:44    Pregnancy at d47, 100% sex semen discussion13:41    Relationship of Luteinizing hormone and progesterone 15:16    What causes elevated circulating progesterone 16:30    How did we land on 2cc of GnRH to begin with? 18:34    Does increased GnRH cause increased twinning?              21:02    What do you want boots on the ground dairymen to know23:01    What if you cherry picked? 23:32    Sometimes the plan doesn’t work – but that’s why we do research! Featured article: Effect of 200 μg of gonadorelin hydrochloride at the first GnRH of a CIDR Synch program on  ovulation rate and pregnancies per AI in Holstein heifers
Articles also discussed in the podcast:Heifer study using 100 and 200 ug in 5-d CIDR Synch protocol. https://doi.org/10.1016/j.theriogenology.2023.04.026
Studies showing the implication of progesterone for double ovulation (a proxy for twining) and progesterone. https://doi.org/10.3168/jds.2018-14410
 
 
 
#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #gnrh; #CIDRsync; #twinning; #pregnancy; #heiferdevelopment; #TAI; #lutenizing; #dairysciencedigest; #ReaganBluel;

DSD 5.2 | Stop fresh cow subclinical mastitis in its tracks without withhold

Getting the fresh cow off to a strong start has ripple effects for her entire lactation. Subclinical mastitis rarely gets treated due to an unawareness or a lack of interest in pulling her from the tank. Nisin is a naturally occurring antimicrobial that’s been used widely as a food preservative. Dr. Zelmar Rodriguez and his team from Michigan State University looked at using this familiar antimicrobial to treat subclinical mastitis. The result, reduced clinical cases of mastitis.
Listen in to learn more about the return on investment of using Nisin on subclinical mastitis found in the first week of milk using CMT.
These findings are published in the recently released paper titled: Economic impact of treatment of subclinical mastitis in early lactation using intramammary nisin
Topics of discussion
1:20       Introduction of Dr. Zelmar Rodriguez 2:20       What is nisin 3:42       No dump milk4:10       Subclinical mastitis assessment 5:00       CMT discussion6:00       What day should we sample7:00       Subclinical mastitis prevention7:39       How does CMT work?8:46       Factors that impact effectiveness              9:18       What will nisin not work on – gram negative discussion12:36    ROI/cow13:23    Treatment regimen 13:42    Assessment to begin protocol15:36    Effect of employee training         17:16    Model at herd level – ROI19:33    FDA status20:22    Limitations of using DHIA hot sheet22:13    What do you want boots on the ground dairymen to knowFeatured article: Economic impact of treatment of subclinical mastitis in early lactation using intramammary nisin
 
#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #nisin; #earlylactation; #subclinical; #mastitis; #treatment; #dairysciencedigest; #ReaganBluel;