Slide 1: The Impact of Daily Rhythms on Milk and Component Yield
The Impact of Daily Rhythms on Milk and Component Yield Dr. Kevin J. Harvatine Professor of Nutritional Physiology Department of Animal Science Penn State University July 2021 Balchem Real Science Lecture Series
Slide 2: Key principles that I hope to convince you of today!
Key principles that I hope to convince you of today! • There is a daily (circadian) pattern of intake that creates large changes in rumen fermentation across the day • There is a daily pattern of milk synthesis • Maximizing efficiency requires synchronizing nutrient absorption and mammary needs • Co
Slide 3: Milk fat and protein is affected by many nutritional and non-nutritional factors
Milk fat and protein is affected by many nutritional and non-nutritional factors! Nutritional Factors Non-nutritional Factors Decreased by milk fat depression - Unsaturated fat Genetics - Fermentability - Acidosis Season - Feeding strategies Fat Milk Fat & Increase by additional substrate Time of da
Slide 4: Circadian/Daily Rhythms in the Dairy Cow
Circadian/Daily Rhythms in the Dairy Cow - Circadian rhythms are 24 hour repeating cycles controlled endogenously - Many biological functions follow a 24 cycle - Activity and Alertness - Nutrient Metabolism - Milk Synthesis - Intake Why?? Allows the animal to anticipate changes and adapt before they
Slide 5: Daily intake and production versus second to second
Remember, we talk about daily intake and production, but the cow lives second to second and minute to minute! - Feed is consumed through meals across the day daily intake = # meals * size meals (5 to 12 meals/day) - Milk is synthesized continuously across the day
Slide 6: Are the daily patterns of nutrient absorption and milk synthesis synchronized?
Are the daily patterns of nutrient absorption and milk synthesis synchronized?
Slide 7: Biological rhythms are repeating cycles driven by a time keeping mechanism
Biological rhythms are repeating cycles that are driven by a time keeping mechanism in the animal and can be reset (entrained) by external factors, like timing of lighting Period - Will be maintained if Amplitude animal is put under constant conditions - Are helpful as they allow the animal to prepa
Slide 8: How does the cow know what time of day it is?
How does the cow know what time of day it is? Environmental Cues • Main environmental cues: Light/Dark – Light/Dark Peripheral rhythms – Feeding Times Master Clock – Milking Time? (SCN- Brain) • A breakdown in the daily Other system creates jetlag! Environmental • A disconnection between Cues lighti
Slide 9: Photoperiod has a large impact on milk yield
We know “Photoperiod” has a large impact on milk yield Constant 16 to 18 h vs. 8 to 10 h light • ~5 to 10% increase in milk yield and no change in milk composition • Additional effect of short days in dry period • Eliminated by constant light -Basic mechanism of photoperiod is through same signaling
Slide 10: Lighting phase disruption during the dry period impacts physiology of the cow
Lighting ”Phase Disruption” during the dry period impact physiology of the cow Phase shifting light during the dry period hematic diagram of the study design. Sixteen multiparous Holstein cows were blocked to either a control (CON) or phase at 35 d before expected calving (BEC). (A) At study enrollm
Slide 11: Is there a daily pattern of feed intake?
Is there a daily pattern of feed intake? Pasture Fed Cows Peak Lact. Late Lact. Sheanhan, Kolver, and Roche, 2011
Slide 12: TMR Feeding: Feeding and milking times are most important
TMR Feeding: Feeding and milking times are most important Feeding and milking commonly both near dawn & dusk in experimental data DeVries et al. 2005
Slide 13: Eating and Ruminating tend to be inverse
Eating and Ruminating tend to be inverse Eating Ruminating Sheanhan, Kolver, and Roche, 2011
Slide 14: Rumination pattern is conserved even during heat stress
Rumination pattern is conserved even 0 during heat stress SORIANI ET AL. Low, Medium, and high Temperature-Humidity Index Daily pattern of rumination time expressed in minutes per 2 h in 3 levels of daily gure 7. Daily pattern of rumination time expressed in minutes per 2 h (least squares means ± SE
Slide 15: PSU Feeding Behavior System
PSU Feeding Behavior System MooMonitor+ Dairymaster (Image Dairymaster.ie)
Slide 16: Feed intake is highest after feeding and in the afternoon
Feed intake is highest after feeding and in the afternoon 2.5 1.0 0.9 2.0 0.8 Starch Intake, kg/h DMI, kg/h 0.7 1.5 0.6 0.5 1.0 l 0.4 0.3 0.5 0.2 0.1 0.0 0.0 0030 0430 0830 1230 1630 2030 0030 0430 0830 1230 1630 2030 Time of Day Time of Day Ying et al. 2015
Slide 17: The feeding pattern is consistent across NDF, starch, and fat levels and types
In experiment 2, pool size of DM, NDF, 120-h in vitro rumination rhythm 3 experiments, so that rumen the acrophase evacuations wereoccurred periment 1, per- indigestible decreasing NDF, NDFincreased and starch concentration decreased by 34, 20, 14, h later. The feeding pattern is consistent across T
Slide 18: What is the impact of the daily pattern of intake?
What is the impact of the daily pattern of intake? Intake = Entrance of fermentable feed into the rumen for microbes to digest Fermentable feed = Synthesis of VFA’s (acids) & microbial protein VFA’s = Acid load for rumen Nutrient supply for cow
Slide 19: What are the rumen changes relative to feeding
What are the rumen changes Rumen DM Pool, kg relative to feeding 16 6.4 15 6.2 Rumen pH 14 13 6.0 12 11 5.8 10 5.6 0000 0600 1200 1800 0030 0430 0830 1230 1630 2030 Time of Day 1.2 14 1.0 Rumen Starch Pool, kg 12 Ammonia, mg/dL 0.8 10 0.6 8 0.4 6 4 0.2 2 0.0 0000 0300 0600 0900 1200 1500 1800 2100 0
Slide 20: Rumen methane also follows a daily pattern
Rumen methane also follows a daily pattern: Jersey cows fed 1 vs 2x/d 10906 JUDY ET AL. Figure 2. Hourly methane production from late-lactation dairy cows fed once daily (1×) at 1000 h or twice daily (2×) at 1000 and 2000 h. Overall methane production per hour was not different (P = 0.445), with a m
Slide 21: Duodenal flow and composition varies across the day
And.. Duodenal flow and composition 246 Gill, Robinson and Kennelly 07.00 varies across the day Diurnal patterns of ruminal digesta flow in cows Time of day (h) 241 Solid Phase Liquid Phase Marker Marker 2 80- 70 -7 9 9 07.00 07.00 I 12.00 1 17.00 I I22.00 I 03.00 I 1 08.00 l 07.00 12.00 17.00 22.00
Slide 22: How flexible is the pattern? Evening feed delivery
How flexible is the pattern? Evening feed delivery increased feed intake after feeding by >50%! Ø ANOVA Effect P-value Treatment 0.78 Time <0.01 Treatment x Time <0.01 Ø Circadian Parameters Treatment Phase/h Amplitude P-value AM 1654 2.0 <0.01 PM 1638* 0.6* <0.01 AMPM 1448* 1.1* <0.01 *Significantl
Slide 23: Increase intake in the evening spikes insulin
Increase intake in the evening spikes insulin Ø ANOVA Effect P-value Treatment 0.76 Time <0.01 Treatment x Time <0.01 Ø Circadian Parameters Treatment Phase/h Amplitude P-value AM 1844 1.8 0.07 PM 0031* 8.3* <0.01 AMPM 2220* 4.8* <0.01 *Significantly (P < 0.05) different from AM vAM vs.PM (O = P < 0
Slide 24: Intake pattern creates a circadian pattern of plasma metabolites and hormones
Intake pattern creates a circadian pattern of plasma metabolites and hormones Insulin Glucose Oba and Allen, 2003
Slide 25: Milk synthesis is variable over the day
Milk synthesis is variable over the day 2x Milked Herds Milk Milk 0.5 Units 2 kg Quist et al. 2008
Slide 26: Theoretical de-synchronization of intake and mammary metabolism
Theoretical de-synchronization of intake and mammary metabolism First test: Fed cows 1x/d or 4x/d in equal feedings
Slide 27: Feeding cows 1x/d vs 4x/d changed milk yield over the day
Feeding cows 1x/d vs 4x/d changed milk yield over the day at one milking Cows were fed either 1x or 4x/d Morning: High volume, low fat and protein% Evening: Low volume, high fat and protein % Rottman et al. (2014) Physiol. Rep. 2:1-12
Slide 28: How does the time of feed restriction affect daily rhythms of milk synthesis?
How does the time of feed restriction affect the daily rhythms of milk synthesis? • 16 Cows • Crossover design DRF: Fed 16 h/d during day (7 AM to 11 PM) • 17 d period NRF: Fed 16 h/d overnight (7 PM to 11 AM) • 7 d of 4x/d milking Salfer et al. Bri. J. Nutr. 2020
Slide 29: Milk yield and composition shifted by night-restricted feeding
Milk yield and fat and protein concentration were shifted by night-restricted feeding DRF: Fed 16 h/d during day (7 AM to 11 PM) NRF: Fed 16 h/d overnight (7 PM to 11 AM) Salfer et al. Bri. J. Nutr. 2020
Slide 30: Plasma glucose and insulin shifted by time of feed restriction
Plasma glucose and insulin concentrations were shifted by the time of feed restriction DRF: Fed 16 h/d during day (7 AM to 11 PM) NRF: Fed 16 h/d overnight (7 PM to 11 AM) Salfer et al. Bri. J. Nutr. 2020
Slide 31: Body temperature rhythm shifted by night-restricted feeding
The daily rhythm of body temperature was shifted 8 h by night-restricted feeding DRF: Fed 16 h/d during day (7 AM to 11 PM) NRF: Fed 16 h/d overnight (7 PM to 11 AM) Salfer et al. Bri. J. Nutr. 2020
Slide 32: Mammary core clock gene expression shifted by night-restricted feeding
Mammary expression of some of the core clock genes was shifted by night- restricted feeding CON: Fed continuously 24 h/d NR: Feed restricted to 16 h at night (8 PM to 12PM) Salfer et al. Unpublished
Slide 33: The mammary core clock was robustly inverted in day vs night fed mice
The mammary core clock was robustly inverted in day vs night fed mice Trt: 0.78 Trt: 0.61 A. CRY2 Time: 0.22 B. PER2 Time: 0.58 Trt×Time: < 0.001 Trt×Time: < 0.001 3.5 18 ** 16 ** mRNA relative expression mRNA relative expression 3 ** ** ** 14 ** ** 2.5 12 2 10 1.5 8 DR 6 NR 1 DR 4 0.5 NR 2 0 0 0600
Slide 34: When do cows prefer to be milked?
When do cows prefer to be milked?? Automated Milking System Hogeveen et al., 2001
Slide 35: How can we use this information?
How can we use this information?? Think not just about the diet we are feeding, but how we are feeding it and how the cows are eating it! We need to watch the cows and see what they are doing!
Slide 36: 1st… Think of the rumen
1st… Think of the rumen • Can we stabilize the amount of fermentable feed entering the rumen over the day? – Take out some of the slugs and fill in during some of the low points
Slide 37: How do we do this?
How do we do this? • Feed delivery is a strong signal for feeding which can be used to increase intake during low intake periods of the day • Make sure feed is available when return from parlor………, but – Delivery of feed 2-3 h before or after milking may spread intake more across the day (King et al
Slide 38: What else can we do?
What else can we do? • Feeding different diets across the day might also work – Feed same ration to entire herd in morning – Return to “top-off” high groups
Slide 39: Feeding multiple rations over the day
Feeding multiple rations over the day • Three diets were used – Control (Con): 30.1% NDF – High fiber (H): 31.8% NDF 70% of H & – Low fiber (L): 26.9% NDF 30% of L = Control • Three Treatments – Fed control TMR once per day at 0900 – High-Low Treatment (HL) • 70% of feed fed as High Fiber Diet at 09
Slide 40: Milk yield and composition
Milk yield and composition Treatment P-value CON HL LH SEM Trt DMI, lbs/d 58.0 53.7c 56.0 2.4 0.01 Milk, lbs/d 87.3 84.9 90.2 5.3 0.14 Milk Fat Percent 3.44 3.39 3.45 0.25 0.73 Yield, lbs/d 2.99 2.82LH 3.10 0.11 0.07 Milk Protein Percent 3.08 3.10 3.10 0.09 0.86 Yield, lbs/d 2.68 2.64 2.79 0.15 0.19
Slide 41: What did we learn?
What did we learn? • Its complicated! • Have to be very careful with the effect of timing of feed delivery changing feeding behavior • Demonstrates we don’t have to have the same TMR across the day and there are times that feeding different diets might be advantageous
Slide 42: Interesting Call From the Field
Interesting Call From the Field • One pen of cows on a large farm consistently 0.3 to 0.5 units lower in milk fat than peer pen in another barn fed same diet • Moved fifteen cows from the pen to another pen and they increased milk fat • Normal MFD troubleshooting turned up no clues • Cows being fed
Slide 43: Must consider multiple factors that have an impact on behavior and physiology
Must consider multiple factors that have an impact on behavior and physiology
Slide 44: Key Principles
Key Principles • There is a daily (circadian) pattern of intake that has a major impact on the rumen • There is a daily pattern of milk synthesis • We need to manage the daily pattern of intake and our best tools for this are through feeding and milking schedules • Don’t be afraid to feed multiple d
Slide 45: Thank You!
Lab Members: Cesar Matamoros, Beckie Bomberger, Alanna Staffin, Abiel Berhane, Yusuf Adeniji, Sarah Bennett, and Ahmed Elzennary. Previous Lab Members: Reilly Pierce, Dr. Rachel Walker, Dr. Chengmin Li, Elle Andreen, Dr. Isaac Salfer, Dr. Daniel Rico, Dr. Michel Baldin, L. Whitney Rottman, Dr. Mutia