Welcome to the ADSA Annual Meeting Dair-e-news

The 2020 ADSA Virtual Annual Meeting is taking place this week in homes and offices around the world. It is off to a great start. Over 2,000 individuals have registered for this year’s meeting making it one of the largest scientific dairy meetings ever. If you still need to register, click here . While COVID-19 has caused the format to change, the purpose is the same, to present the premier global dairy science meeting in the world!

 

This year’s meeting features more than 100 hours of programming delivered through approximately 800 scientific presentations, panel discussions with live Q&A, live roundtable discussions available in several time zones, an exhibit hall, additional networking opportunities, and student competitions. As always, we will facilitate focused, meaningful, and interesting discussions about the latest dairy science and its applications. It is considered the most comprehensive dairy science meeting in the world and is where the latest ideas and findings in the industry are being discussed.

We once again are pleased to be sending "Special Editions" of this newsletter to you from the virtual meeting. An outstanding group of graduate students is working with us to help provide daily coverage of scientific sessions and other activities taking place throughout the meeting.

 

One of today’s special events was the Annual Awards ceremony recognizing members for their outstanding work. You can find the award booklet that includes information on all award winners and sponsors by clicking here . 

 

If you have not yet registered, you can still join in! Learn more and register here . And, save the date for next year's annual meeting in Louisville, Kentucky, July 11-14, 2021. Make your plans now to attend.

Heat Stress? No sweat with new management insights!

By Miriam Snider

Heat stress and heat stress management were the topics for the first block of the Production, Management, and Environment session at this year’s American Dairy Science Association Virtual Meeting with Jen Heguy serving as the moderator. Heat stress is one of the leading causes of decreased production in dairy cattle during the summer months and can become apparent due to decreased milk production and decreased breeding cycles. Although heat stress is unavoidable, researchers are studying methods to minimize the effects, whether that be through better genetics and housing to assessing new methodologies for detection.

 

First, researchers from the University of Florida assessed the effects of heat stress on the time budget of nulliparous Holstein heifers. Toledo et al. housed 25 pregnant Holstein heifers in freestall barns. Heifers either received shade as the heat stress treatment or shade, soakers, and fans as the cooling treatment. Leg and neck tags were used to record steps, standing, eating, rumination, and lying time. It was found that heat stressed animals spent more time eating but less time ruminating during the prepartum period. However, during the postpartum period, heat stressed heifers, while still eating more and larger evening meals, did not differ from non-heat stressed animals when it came to rumination time. Heat stressed heifers also took more steps during the postpartum period. This suggests that heat stress does affect the daily time budget during the pre- and postpartum periods. Although animals were eating, they were attempting to mitigate internal body heat, hence less time ruminating. Management strategies could be developed from this information to help producers mitigate cow heat load.

 

Chaalia et al. from the Universitat Autonoma de Barcelona switched things up by identifying metabolic and productive characteristics in dairy sheep that were either sensitive to heat or thermotolerant. Twenty-four Manchega dairy ewes in late lactation underwent a short-term heat challenge in a temperature-controlled room. Rectal temperature (RT) and respiratory rate (RR) were measured, with ewes classified by the RT/ RR change ratio (CR). Ten ewes from the original 24 differing in CR were then used in a crossover study with two periods (3 weeks each) and two climatic conditions (thermoneutral and heat stress), with RT, RR, milk yield, and intake being measured. Heat stressed ewes had greater prolactin concentrations and decreased milk fat and protein. No noticeable differences were noted with other measurements. This suggests that although there were slight differences between the two treatment groups, Manchega ewes, overall, were relatively tolerant to heat stress. Stage of lactation or phenotype of animals may contribute to overall sensitivity to heat.

 

Toledo et al. presented once again and discussed various management challenges regarding the relationship of pasture housing and heat stress in late pregnant heifers. In this study, Holstein heifers were housed on pasture or in a freestall barn. Heifers were either exposed to a heat stress challenge or cooled with shade, soakers, and fans. Temperature-humidity index and black globe temperature were measured as well lying time, steps, eating, and rumination time. Pasture heifers spent less time lying down, less time ruminating, and more time walking when compared to heifers confined to a freestall barn. This indicates that heat stress does affect the daily time budget of pregnant heifers, especially if they are on pasture. It may give insight into developing new management strategies to mitigate heat stress.

 

Finally, Ouellet et al. from the University of Florida discussed new methods for assessing chronic heat stress in dairy calves in a subtropical environment. Heat stress in dairy calves has received less attention because it is believed that they are more tolerant to heat stress. In this study, researchers measured respiration rate, rectal temperature, and skin temperature in dairy calves exposed to a heat stress challenge or kept cool. Environmental conditions, such as ambient temperature, humidity, THI, and wind were also measured. A positive correlation was noted between animal-based indicators, ambient temperature, and THI. Results indicate that dairy calves can undergo heat stress with THI being the best environmental indicator of heat stress. Practically, heat mitigation should be applied when THI reaches 65 if calves are exposed to chronic heat stress; in a subtropical environment, calves should be monitored between a THI of 65 and 69. This means that producers should adapt their management strategies to account for heat stress for every member of their herd.

Miriam Snider is a PhD candidate at the University of Vermont under Dr. Sabrina Greenwood. She earned her B.S. in Animal Science / Biology from Southeast Missouri State University and her M.S. from the University of Kentucky. Her current research explores forage and pasture quality/ energetics and its relationship with rumen fermentation and methane production.

Graduate student symposium offers writing tips

By Sonali Raghunath

During the ADSA virtual meeting Dr. Vernetta Willams hosted a session focused on Thesis/ Dissertation writing from Cultivate the Writer organized by GSD ADSA with 45+ attendees. Her workshop was more focused on how to manage the timeline, tips on writing and most importantly issues with word formatting. It was a resourceful workshop, which is much needed for graduate students across the world with thesis and dissertation. Here are some of the highlights and tips from the workshop:

Time and project management

Deadlines: Plan your thesis/Dissertation according to the deadlines fixed in various stages at the University

Plan: A working plan on how to approach the thesis and dissertation, strategy towards the plan and find your support without the sense of isolation

Rewards: Always reward yourself for your successful weekly productive plans

Checklist: Jot down each chapter in your thesis/ Dissertation and add points to each chapter and how you will be discussing in the chapter.

Literature Review: What is currently out there about your topic? Concepts, themes, definitions

Conclusion: Similar to literature review, what can you conclude about your topic based on older studies

Writing process

Foundational structure : Introduction, body and conclusion

Body paragraph : Break up each paragraph into sentences with topic sentence, supporting sentence, detailing sentence and concluding sentence.

Check : Outline your ideas, perfect your topic sentences and sufficient support sentences, and check the topic sentences with the topic of your thesis/ Dissertation

Word formatting/ Conciseness

Passive/Active voice : Adjust the style according to the audience – Publications

Passive voice strategy: Use when you want to emphasis more on the object than the subject who did it. Eg: Emphasis on datasets instead of the subject

Expletives : An empty word and inverts the sentence order. There and it are most commonly used sentences structures for Eg: It should be noted that …. (What does “it” refer to?) and can be removed from sentences and start with the subject/object

Nominalizations : Using a verb in noun form also helpful (Avoid the use of helping verbs and other empty words)

Empty/ Inflated phrase : A group of words with no or little meaning. Eg: “Due to the fact” which can be changed to single word “because”

Sonali Raghunath is a PhD student in Food Science at the University of Minnesota under Dr.Tonya Schoenfuss and Dr. Kumar Mallikarjunan. She earned her M.S. in Food Science from University of Minnesota and her B.Tech in Food Technology from Anna University, India. Her current research explores the relationship between non-thermal processing methods and milk protein concentrate.

Uterine diseases, postpartum metabolic disorders explored

By Iswarya Rajesh

Uterine diseases and metabolic disorders affect the early return of the cyclicity of animals and increase the calving interval, affecting reproductive outcomes. It is important to identify these diseases and treat them to bring the cows to heat and successful pregnancy after calving. The carry-over effect associated with the postpartum uterine disease causes more pregnancy loss. 

Researchers from the University of Florida Gainesville reported that experimentally induced endometritis affects milk production at the early lactation. Here 38 clinically healthy cows were selected and synchronized for the estrous starting 38DIM. Cows were divided into control (n=19) and experimental group (n=19), where the experimental group was infused with E. coli and T. pyogenese around 46 days in milk (DIM). The significantly high inflammatory response was observed in the experimental groups compared to the control group, causing subclinical endometritis. They reported a reduction in milk yield in the cows induced for endometritis than the control cows.

Like a uterine disease, the postpartum metabolic disorder affects the animal’s production and reproduction, leading to a higher economic loss. Researchers from the University of Minnesota Saint Paul, MN and Ajinomoto Co. Inc Kawasaki, Japan assessed the accuracy and test characteristics of a multivariate metabolic index (MI) to predict early hyperketonemia in early postpartum Holstein cows. MI is a machine that analyzes the blood metabolites and amino acid prepartum which was associated with postpartum hyperketonemia. They reported the diagnostic accuracy of the MI was 79% to predict the hyperketonemia. The sensitivity, specificity, positive predictive value and negative predictive value was of 75%, 76%, 31% and 95%, respectively.

The MI was able to predict hyperketonemia 3 weeks before the clinical disease with higher accuracy and acceptable test characteristics. Further validation to use in multistate is currently ongoing says Caixeta.

Iswarya Rajesh is a Master's student at the University of Alberta, supervised by Dr. Ambrose and working on the Reproductive Physiology of dairy cows. Rajesh earned a  B.V.Sc  & AH degree from Tamil Nadu Veterinary and Animal Sciences University, India in 2017.

Agrivoltaics as heat stress abatement

By Haley Zynda

The dairy industry has been striving to improve its sustainability regarding greenhouse gas emissions, water use, and land use. While a lot of research has been done with nutrition to reduce methane and ammonia emissions, some land use research is up and coming.

Agrivoltaics, or the integration of solar energy and agriculture, may be the future of increased land efficiency. Solar energy and agriculture have historically competed for land but building photovoltaic (PV) panels in pasture may be a compromise with multiple benefits.

One of these benefits is heat stress abatement. Heat stress has been known to decrease performance of lactating cows, thus decreasing overall productivity and profitability in the hot summer months. Free stall housing can utilize fans and misters to lessen the effects of heat and humidity, but cows housed in a pasture setting unfortunately do not have those luxuries. Installing PV panels may offer shade to minimize the effects of heat stress on cows in pasture-based dairies.

A study done by researchers at the University of Minnesota sought to examine this method of abatement using twenty-four crossbred dairy cows during peak heat stress months (June through September). Half of the cows were pastured with shade from PV panels or no shade (control). Lactation performance, hygiene, and fly presence were recorded during the study.

Results of this study did show that shade from PV panels significantly reduced the severity of heat stress as indicated by a decreased respiratory rate and body temperature during the hottest portion of the day compared with the control cows. While no difference was seen in milk yield or milk fat and protein yield, more research is needed to understand long-term implications of reduced heat stress on pasture. Furthermore, agrivoltaics may be a plausible way to reduce heat stress in a variety of cattle operations, from organic pasture-based dairies to heifer growers to feedlot steers. Although more research needs to be done on the economic side of this feat, dairy producers may be able to have dual-income fields or wire their facilities to run on the solar energy they produce.

Haley Zynda is a Master’s student under Dr. Chanhee Lee at The Ohio State University. She is studying dairy nutrition, specifically diet manipulation to reduce manure emissions. 

Tools, technologies, data to improve environmental management

By Miriam Snider

Dairy production and management rely on a variety of tools and technologies, especially when facing ever-changing climate challenges. In this second session of Production, Management, and the Environment, moderated by Jen Heguy, researchers focused specifically on various management tools, technologies, and surveys that would be beneficial to the farmer, consumer, and the environment.

Researchers from the USDA-ARS and the University of Wisconsin presented research assessing the environment of dairy farms in the eastern United States. In this study, researchers identified a need for a comprehensive evaluation of environmental impacts of dairy farms, regionally and nationally, so as to improve the dairy industry. Rotz et al. used process level simulation and life cycle assessments in the eastern United States. This project was born out of a study that was first developed for the beef industry. It was found that eastern dairy farms produced the smallest amounts of greenhouse gases and used fewer fossil fuels and blue, or non-precipitation, water than other farms when comparing total estimates. The greatest environmental concern appears to be ammonia emissions as dairy farms were found to contribute 65% of estimates for the region. Environmental footprints varied greatly among farms and was influenced by climate, soil, and farm management. The main takeaway is that prescriptive mitigation strategies for individual farms is more effective than uniform enforcement.

Warner et al. discussed using bulk tank milk fatty acid profiles as an on-farm decision support tool.

Researchers created a database from 3,395 dairy herds using milk recording and mid-infrared (MIR) spectroscopy in Quebec, Canada in order to create a benchmarking system. Seasonal cycles showed a decrease in de novo fatty acids and an increase in pre-formed fatty acid during the summer months. By having a database, researchers may be able to see fatty acid changes before other components, acting as an early indicator that something is going on and needs to changed. This will benefit the farmer economically as well as improve cow her health. Additionally, using MIR is a cheap method of analyzation and could be a valuable tool for management and feeding.

To close out this session, researchers from the University of Maine, Atlantic Corporation, and the University of Southern Maine conducted a survey to evaluate dairy food preference and purchases interests of consumers on a national scale. An online survey was conducted with over 20,000 participants from across the United States. Data was parsed by national, regional, and state results. A unique aspect of this study was that regression statistics were used to predict demographic and non-demographic factors that may contribute to consumer preferences. The data from this survey has helped guide the development of an online tool for both farmers and processors to better understand consumer food preferences in their marketing area. The main take away is that this data has driven the development of economic models that are able to predict what consumers want to buy and from who they’re willing to buy from. There may be some opportunities to educate consumers about local dairy products that may be available to them. People find dairy foods to be comforting and knowing where your food comes from may be a real opportunity for dairy farmers.

Miriam Snider is a PhD candidate at the University of Vermont under Dr. Sabrina Greenwood. She earned her B.S. in Animal Science / Biology from Southeast Missouri State University and her M.S. from the University of Kentucky. Her current research explores forage and pasture quality/ energetics and its relationship with rumen fermentation and methane production.

Students compete in ADSA Production PhD Oral Competition

By Ashley Putman

Eleven PhD students navigated the changes from an on-site meeting to a virtual one to disseminate their work and compete in the 2020 ADSA Production PhD Oral Competition. Although the competition was held in a non-traditional manner, with the students pre-recording their presentations and meeting with the judges at a later date via Zoom to answer questions, the virtual format of the meeting did not hinder the students’ ability to provide outstanding presentations.

While each presentation was unique, fatty acids were a common theme amongst some of the presentations. For instance, Zorini discussed that feeding Camelina sativa cake (a source of omega-3 fatty acids) may have beneficial effects on dairy cow reproductive outcomes, along with other beneficial effects. Work presented by Walker and Putman showed that products of different fatty acid metabolism pathways may be beneficial to dairy cattle under challenges associated with mastitis. Busato spoke to the ability of individual and combinations of fatty acids to activate PPAR, finding that combinations of certain fatty acids activated PPAR more so than the individuals.

Beyond fatty acids, many other important areas of study were included in the competition. For example, Dorji described that mitochondrial protein gene expression was associated with feed efficiency and energy demands although there was a low amount of mitochondrial genomic diversity within dairy breeds. Fontoura discussed how an organic acid and plant botanical supplement had beneficial effects on heat-stressed calves. Fehlberg demonstrated that dairy cows fed rumen protected lysine prior to calving had increased energy-corrected and fat-corrected milk, among other milk components and dry matter intake postpartum. Tebbe discussed findings that fresh cows being fed high amounts of metabolizable protein are benefitted by being fed a mixture of rumen undegradable protein and rumen protected amino acids. Additionally, it was suggested that forage neutral detergent fiber may be required more by multiparous cows than primiparous cows. Metritis was the topic of Figueiredo’s presentation, where it was discussed that delayed clinical cure of metritis resulted in negative reproductive outcomes, such as delayed return to cyclicity. Klopp showed that the percent fat of colostrum is associated with certain lipids, such as phosphotidylcholine. Seely demonstrated that there is a very consistent pattern in in plasma and milk BHB and NEFA concentrations throughout a day and that hyperketonemic cows had greater changes of plasma BHB within a day.  

An awards ceremony was held Monday evening, where Carsten Walker (Michigan State University) was awarded first place, Alex Tebbe (The Ohio State University) was awarded second place, and Rebecca Klopp (Purdue University) was awarded third place. Congratulations to this year’s winners!

Ashley Putman is a recently graduated veterinarian and PhD candidate in the Meadow Brook Endowed Laboratory at Michigan State University. Under the guidance of Dr. Lorraine Sordillo, she focuses on the physiological role of isoprostanes, a biomarker of oxidative stress, on bovine health and disease.

Session focused on dairy phospholipids

By Kaavya Rathnakumar

The Dairy Foods Processing session consisted of four presentations by different speakers, Carmen Moraru moderated the session with a brief introduction on herself and gave the room for each presenter to briefly elucidate their research work.

A. Ubeyitogullari, a postdoc researcher from the Cornell University illustrated his work on the production of 76% high purity phospholipids from the spray-dried buttermilk powder by employing ethanol-modified supercritical carbon-di-oxide, he added the opportunities of value addition of PLs in emulsifiers.

K.Rathnakumar from the South Dakota state university emphasized the change in hydrophilicity by adding and removing CO ₂ of the novel Switchable solvents helped to extract the phospholipids from dairy by-products beta serum and buttermilk. This process helped in the reduction of steps from the multistep procedure such as concentration, filtration nor distillation.

A.V.Swaminathan, a PhD student from the University of Wisconsin, her research focused on the production of enriched phospholipid concentrate from the dairy byproduct Whey protein phospholipid concentrate (WPPC), she highlighted the fact the extraction process as the non-solvent system and was able to concentrate from 5% to 10% phospholipids in a pilot scale.

Overall this session of dairy food processing focussed more on the production of dairy phospholipids using different techniques and methodologies. The Milk Phospholipids are gaining more attention these days because of its health and nutritional benefits as well as the potential applications in processing aids.

Kaavya Rathnakumar is a Graduate Research Assistant, PhD, Dairy Manufacturing, South Dakota State University.

Rumen microbial manipulation by feed supplements, additives

By Miriam Snider

Rumen microbes are responsible for a variety of functions in ruminant animals, ranging from methane and VFA production to nitrogen utilization and optimizing milk production. Dietary manipulation is viewed as one of the most effective methods of altering the rumen microbiome, in turn altering fermentation patterns and digestion. In this session moderated by Dr. Jeff Firkins from Ruminant Nutrition: Gut Physiology, Fermentation, and Digestion, researchers presented findings pertaining to feed supplements and additives that may impact ruminant nutrition by modifying rumen microbe function.

In the first presentation of this session, Pitta et al. evaluated the effects of 3-nitrooxypropanol (3NOP) on gene expression of rumen microbes in dairy cattle. 3NOP is a methane inhibitor that may reduce enteric methane emissions in dairy cattle. In this study, researchers used metatranscriptomics to investigate the effects of 3NOP on methanogen inhibition in dairy cows fed silage-based diets. Four cows received a diet supplemented with 3NOP and 4 received the control diet. Rumen contents from 8 ruminally cannulated early-lactation dairy cows were sampled at 2, 6, and 10 hours after feeding using a randomized complete block design. Rumen samples were extracted for RNA then reverse transcribed to cDNA which led to the development of sequencing libraries. From this study, 3 methanogenesis pathways were identified with the hydrogenotrophic pathway being the predominant pathway. This pathway was carried out by 6 Methnobrevibacter species with the most abundant archaeal transcripts encoding chains of methyl co-enzyme reductase (MCR), which aids in methane formation. Based on these results, it can be deduced that 3NOP reduced MCR transcripts with a 25% reduction in enteric methane; inhibition of MCR by 3NOP is responsible for methane reduction.

Pitta et al. continued by reviewing the effects of 3NOP and its effects on ruminal methanogens. In this study, researchers investigated the effect of 3NOP on total and metabolically active methanogens over the course of a day for a 12-week period. The study was conducted similarly to the previous study. Rumen samples were extracted for microbial DNA and RNA and sequenced for Archaea diversity. It was found that methanogens do have different metabolic capacities. The dominant genus was Methanobrevibacter followed by Methanosphaera. Methanosphaera populations more metabolically active and were more abundant at 2 hours as opposed to 6 and 10 hours. The reverse was true for Methanobrevibacter. This indicates that Methanosphaera may increase following feed intake and may help more in methane formation than previously thought.

Finally, moving away from 3NOP, Ray et al. reported their findings from a study assessing the role of oregano essential oil on gut microbe modulation and antibiotic resistance in calves. Five Holstein bull calves were fed a control (waste milk) and 5 were fed oregano essential oil. Fecal samples were collected during the study period and analyzed for antibiotic-resistant E. coli colonies. Genomic DNA was then extracted, amplified, and sequenced. Across all samples, Firmicutes and Actinobacteria were the two most dominant phyla, with Actinobacteria being in greater abundance in calves fed oregano oil. Firmicutes was more predominant in control calves. Higher populations of Arthrobacter were correlated with greater numbers of Cryptosporidum eggs Calves fed oregano oil tended to have lower populations of both Escherichia and Arthrobacter, which indicates oregano oil influences gut microbial populations. These results indicate that feeding oregano oil to calves may reduce parasite loads and antibiotic resistant bacteria, which could lead to modified management strategies.

Miriam Snider is a PhD candidate at the University of Vermont under Dr. Sabrina Greenwood. She earned her B.S. in Animal Science / Biology from Southeast Missouri State University and her M.S. from the University of Kentucky. Her current research explores forage and pasture quality/ energetics and its relationship with rumen fermentation and methane production.

Production, Management, and the Environment

poster session addresses numerous topics

By Ashley Putman

A wide range of topics were discussed in the poster session for Production, Management, and the Environment on Monday. Broadly, studies touched on relevant diseases, estrus detection, diet, changes in body condition and muscle mass, and calves and rearing conditions.

With mastitis being one of the major diseases afflicting dairy cattle, it is important to determine factors that may contribute to cows developing the disease. France reported that housing transition cows on compost bedded packs likely does not influence teat microbial populations while Turiello discussed producer understanding and application of various aspects of mammary health programs. Zhang also discussed research relevant to mastitis by evaluating the use of a chitosan-containing teat dip. Valldecabres presented on hypocalcemia, another important dairy cattle disease, noting that serum calcium concentrations <2.18 mmol/L were associated with higher milk yield, energy-corrected milk yield, and milk fat % while decreasing milk protein percentage. Heat stress is known to cause negative impacts in dairy cattle, and therefore research pertaining to this topic is necessary to advance dairy cow health. One heat stress-related study presented by Franzoni showed that heat stress levels had a low correlation to seasonality of milk yield after correction for parity and days in milk. Heat stress negatively impacted rumination time and ruminal degradability in dairy cows as noted by Pereira while an organic acid and plant botanical supplement had beneficial effects on heat-stressed calves as stated by Fontoura.

Highlights from the remaining presentations include the findings delivered by Gallardo that showed feeding leftover lactating rations to dry cows is associated with increased fat mobilization during early lactation and McCabe’s findings that a substantial amount of muscle is mobilized during the first two months of lactation. White discussed the potential of minimizing effects to diet costs while decreasing phosphorus balance and Pereira reported that >80% estrus detection can occur accurately six hours prior to the event when utilizing machine learning techniques. Calves had decreased concentrations of serum immunoglobulin G and total protein in their first two weeks of life, according to Correa. Additionally, the rearing method chosen may effect primiparous cow behavior and performance as presented by Broucek. Finally, Lemay discussed how the chosen harvesting time of switchgrass can impact milk components.

Ashley Putman is a recently graduated veterinarian and PhD candidate in the Meadow Brook Endowed Laboratory at Michigan State University. Under the guidance of Dr. Lorraine Sordillo, she focuses on the physiological role of isoprostanes, a biomarker of oxidative stress, on bovine health and disease.

Managing cow health during transition period

By Arup Ratan

Transition period is one of the most critical period in dairy cows life. Managing dairy cows for successful transition from a non-lactating pregnant state to a lactating non-pregnant state could reduce metabolic and infectious disease severity and improve production.

Hypocalcemia or milk fever during transition period is common in dairy cow, characterized by low blood calcium (Ca) level. Research shows that lowering dietary cation-anion difference (DCAD) increases Ca level at calving and reduce the risk for clinical milk fever. DCAD is also negatively correlated with urine pH. Researcher from the University of Georgia showed the association of prepartum urine pH with plasma total Ca (tCa), magnesium (tMg), phosphorus (P), and β-hydroxybutyrate (BHB) in Holstein cows fed negative DCAD diet. With prepartum urine pH < 6.0 and pH > 7.5, cows had lower plasma tCa and tended to have higher BHB. Their study reinforced the importance of keeping urine pH in between 6.0 to 7.5 in cows fed negative DCAD diet.

Like Ca, energy metabolites like BHB, glucose, and free fatty acid (FFA) could also be associated with transition cow diseases postpartum. Researchers from Texas Tech University studied the association between plasma tCa and energy metabolites with early lactation diseases, culling, and milk production. Their study indicated that lower tCa and higher FFA and glucose concentration in blood at 3 days in milk (DIM) were associated with increased risk of culling. Cows with increased BHB concentration at 3 DIM had higher risk of metritis and clinical mastitis. Milk production was positively associated with reduced tCa in the first 2 DIM, reduced glucose at 3 DIM, and increased FFA at 3 DIM. However, increased FFA at 3 DIM also increased the risk of metritis.

Use of non-steroidal anti-inflammatory drugs (NSAIDs) to reduce inflammation for improving cow health in transition cow has been the focus of some recent studies. Researchers from the Kansas State University presented the effect of carprofen (NSAID) on blood inflammation biomarkers and early lactation diseases in transition Holstein cows. Blood inflammation biomarkers like total plasma protein and maresin 1 were higher in cows treated with carprofen 12 to 48 hrs postpartum. Clinical metritis incidence was lower in carprofen treated cow. Their study suggested carprofen treated cow had reduced systemic inflammation postpartum, promoting cow health.

Arup Ratan Sen is from Bangladesh. He is currently a Ph.D. student at the University of Tennessee under the mentorship of Dr. Elizabeth Eckelkamp, focusing on producers perception farm management that impacts their permanency in the dairy industry.

Sensors used in monitoring parameters associated with metritis

By Iswarya Rajesh

An increase in the herd size creates a need for a greater number of labors. Precision farming is slowly being adopted in the dairy farms across the US and Canada as it reduces the need for labor and enhances early identification of many problems by indirectly measuring parameters like activity, feed intake levels and rumination status, etc. Researchers from Cornell University are working on the integrated data obtained from various sensors and performance records in creating a health alert tool that identifies the health disorders in real-time.

Pérez and his colleagues reported the differences in the behavior, physiology and performance among the cows with no clinical metritis group (NCD), with metritis (MET), and other health diseases in addition to metritis (MET+).

They have conducted a prospective observational cohort study with 1211 cows in a commercial farm, which included nulliparous and multiparous cows. The sensors for behavioral and physiological data were fitted 30 days prepartum and the sensor for performance was fitted at day 0 (day of calving). These sensors were then allowed to stay until 35 days in milk (DIM). The data from -7 to + 7 days was compared, where, day 0 marked as the day of the clinical diagnosis. The cows were observed from day 0 to +7 by clinical and visual examination for the presence of health disorders.

The data was analyzed by the MIXED procedure of SAS. They have reported that the physical activity, rumination behavior, eating behavior, milk yield was lower in cows of MET AND MET+ groups compared to the cows in the NCD group. whereas the reticulo- rumen temperature, milk fat%, fat protein ratio was higher in cows of MET and MET+ group compared to the cows in the NCD group. The researchers also reported a significant interaction between day and group of cows in the behavioral, physiology and performance parameters of the cows.

Many of these parameters changed even before the diagnosis of the clinical disorder providing an excellent option for early diagnosis says, Pérez.

Iswarya Rajesh is a Master's student at the University of Alberta, supervised by Dr. Ambrose and working on the Reproductive Physiology of dairy cows. Rajesh earned a  B.V.Sc  & AH degree from Tamil Nadu Veterinary and Animal Sciences University, India in 2017.