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Metabolic changes in transition cows – opportunities for management. Thomas R. Overton Associate Professor of Animal Science Director, PRO-DAIRY Cornell University. The outcome challenge. High milk production Maintain/minimize loss of BCS Low incidence of metabolic disorders
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Metabolic changes in transition cows – opportunities for management Thomas R. Overton Associate Professor of Animal Science Director, PRO-DAIRY Cornell University
The outcome challenge • High milk production • Maintain/minimize loss of BCS • Low incidence of metabolic disorders • Minimize loss of immunocompetence • Control/decrease days to first ovulation and maintain/enhance fertility • Make $$
Energy intake and energy balance Milk energy and energy balance r2 = 0.07 r2 = 0.57 Santos et al. (2010) Reprod. Dom. Rum. VII:387-404
The metabolism challenge required to meet the outcome challenge • Abrupt changes in demands for energy (and other nutrients) • High gluconeogenic rates during postcalving period • Minimize negative diet and management interactions with metabolism (esp. adipose) • Maintain sufficient DMI during precalving period and facilitate acceleration during postcalving period • Manage interactions of facility/nonnutritional management factors with metabolism?
Metabolic Adaptation (Schoenberg, 2010) Increased mobilization of fatty acids Decreased insulin response of adipose tissue Impaired glucose disposal Increased hepatic gluconeogenesis Decreased uptake of glucose by peripheral tissues Changes in intake Glucose sparing for gravid uterus and eventually the mammary gland
Take homes • Coordination of metabolism to support late pregnancy and early lactation is extensive and exquisite • “Insulin resistance” to spare glucose for fetus and mammary gland is important for successful adaptation to lactation • Some degree of fat mobilization (and elevated NEFA) is “normal” • Excessive mobilization of fat (elevated NEFA) is associated with metabolic disorders, lower milk production, and poorer reproductive performance • “Excessive” insulin resistance in body fat likely contributes to hypermobilization of NEFA and lower DMI (cows resemble Type II diabetics) • Fat cows • Cows overfed energy during either far-off or close-up period • Impact of environmental stressors?
DMI and NEFA Adapted from Smith, 2004
Summary of metabolic regulation work focused on insulin resistance • Glucose disposal slower and slope of NEFA decrease less following glucose challenge in prepartum cows compared to early lactation • Smith et al., 2004. J. Dairy Sci. 87(Suppl. 1):442. • Strengthening adipose tissue responses to insulin using targeted approaches in prepartum cows • Decreased NEFA spike during immediate periparturient period • Smith et al., 2007. J. Dairy Sci. 90:3660-3670; • Smith et al., 2009. J. Dairy Sci. 92: 3623-3633 • Increased DMI during immediate periparturient period • Smith et al., 2007. J. Dairy Sci. 90:3660-3670; • Smith et al., 2009. J. Dairy Sci. 92: 3623-3633 • Decreased BCS loss during early lactation and days to first ovulation • Smith et al., 2009. J. Dairy Sci. 92: 3623-3633
Excessive prepartum energy intake and insulin resistance • Mashek and Grummer (2003) • Large decreases in prepartum DMI → higher NEFA, liver TG postpartum • Holtenius et al. (2003); Agenas et al. (2003) • Prepartum overfeeding (178%) → higher glucose and insulin prepartum, higher insulin response to glucose challenge, higher postpartum NEFA, lower DMI postpartum • Dann et al. (2006) • Far-off overfeeding (150%) → higher postpartum NEFA and BHBA, lower postpartum DMI • Douglas et al. (2006) • Lower glucose and insulin prepartum, lower NEFA and higher DMI postpartum in cows fed 80% vs. 160% prepartum • Schoenberg et al. (2010) • Decreased NEFA clearance following glucose challenge in cows overfed during the dry period
Dry period energy formulation from herd to herd is a bit like walking a balance beam • If cows consume insufficient energy, more metabolic problems postcalving • If cows consume excessive energy, more metabolic problems postcalving • MAJOR influence of nonnutritional factors on AMOUNT and UNIFORMITY of energy intake during both the far-off and close-up periods • Dictates different approaches on different farms to achieve same goal
U.S. trends in last 5 to 7 years • Largely abandoned “steam up” concept advocated by 2001 Dairy NRC • Controlled energy strategies for dry cows during both far-off and close-up periods (Drackley, 2007) • 0.59 to 0.62 Mcal/lb of NEL • 12 to 16% starch • 40 to 50% forage NDF • Appropriate for multiparous cows • Too low energy/too bulky for primiparous cows? • MP supply?? (RUP supplementation even more important)
Effects of far-off diet (Dann et al., 2006) • Fed far off cows to achieve • Control (100% of predicted NRC energy requirement – actual 95%) • High energy density diet • 80% of energy requirements • 150% (actual 160%) of energy requirements • Close-up diet to achieve • 135% vs 80% of energy requirements • Cows overfed far-off had • Lower subsequent DMI and calculated energy balance • Higher NEFA and BHB during first 10 d postpartum • Close-up strategy did not affect periparturient metabolism or performance
Richards et al. (2009) • Controlled energy (~ 0.60 Mcal/lb) during entire dry period • High energy (~0.73 Mcal/lb) during entire dry period • Controlled energy far off followed by high energy close up • High energy for entire dry period • Gained more BCS during dry period • Lost more BCS during postpartum period • Controlled energy for entire dry period • Lower postpartum NEFA, BHB, and liver fat compared to high energy • Metabolic health for cows fed two-group more similar to controlled energy than high energy
Common observations with prepartum overfeeding/excessive insulin resistance • Large decreases in DMI as cows approach calving • Low/sluggish increases in DMI in fresh cows • Rapid BCS loss during postpartum period • Higher incidence of subclinical and clinical ketosis and DA • Sometimes lower colostrum yield
Can you go too low? • Janovick and Drackley (2010) • Cows fed low energy dry cow diets (1.21 vs. 1.63 Mcal NEL/kg) had higher postpartum DMI, lower NEFA, better energy balance, but also yielded less milk (33.3 vs 38.9 kg/d for wk 1-8) • Silva del Rio et al. (2010) • Cows fed higher energy diet for entire dry period (1.54 Mcal/kg for 8 wk vs. 1.32 Mcal/kg for far-off and then 1.54 Mcal/kg diet for last 3 wk) had lower energy balance because of increased milk yield and higher postpartum NEFA
Overall goals for energy intake of both far-off and close-up cows • Far off cows (dry off until ~ 3 weeks precalving) • ~ 15 - 17 Mcal of NEL per day • 110 to 120% of ME requirements (CNCPS 6.1) • Close-up cows (last 3 weeks before calving) • ~16 - 18 Mcal of NEL per day • 110 to 120% of ME requirements (CNCPS 6.1) • Vary energy density of diets based upon group DMI • Which means have to know DMI to know how much to “bulk up” the diet • Almost want to achieve the above in the largest DMI package that cows will consume consistently
You HAVE to chop the %(*(#*@&# straw/hay 3.5 lbs straw in 26 lb DM package 6 lbs straw in 27 lb DM package
Potential management/facility related stressors for transition cows • Overcrowding (increased stocking density) • Commingling of cows and heifers • Excessive number of pen moves (group changes) • Heat stress • Overall cow comfort/hygiene
Physiological measures of stress and inflammation? Changes in the activity and functioning of the hypothalamic-pituitary-adrenal (HPA) axis are often used to quantify an animal’s response to a potential stressor. • Plasma cortisol • Non-invasive measures of stress? • Fecal Cortisol Metabolites(Möstl and Palme) Environmental stressors can also induce an acute phase response in cattle. • Haptoglobin
Prepartumhaptoglobin is not associated with postpartum disease Haptoglobin is a non-specific marker of inflammation, infection or injury No differences in prepartum Haptoglobin between health categories. (Huzzey et al., Submitted for review 2010)
Fecal cortisol during wk -2 and -1 were higher in cows that developed more than one health disorder or died by 30 DIM (Huzzey et al., Submitted for review 2010)
% Cows Above Cutpoint: wk -3 wk -2 wk-1 wk+1 Primiparous Multiparous Haptoglobin and milk production (Huzzey et al., 2010) Haptoglobin wk -3 wk -2 wk-1 wk+1 † ∆ 305ME (kg milk) * *** † ** Cutpoint: >1.1 g/L
% Cows Above Cutpoint: wk -3 wk -2 wk-1 wk+1 Primiparous Multiparous Fecal cortisol and milk production (Huzzey et al., 2010) Fecal Cortisol wk -3 wk -2 wk-1 wk+1 ∆ 305ME (kg milk) * ** *** Cutpoint: 250 ng/g fecal DM 70 ng/g fecal DM
Overstocking affects behavior • Increased aggression • Reduced feeding times • Increased feeding rate • Increased inactive standing time • Reduced lying time Little work has evaluated how these behavioral changes influence subsequent health
Overstocking and metabolism Treatments (6 cows and 4 springers per group) Control: Full access to feed bunk (~2 ft/cow) and lying stalls (10stalls/10cow) Overcrowded: 50% less feed bunk space (~1 ft/cow) and lying stalls (5 stalls /10 cows) Huzzey, Nydam, Grant, and Overton, 2010 Cornell Nutrition Conference
Competition for feed Standard Overstocked Huzzey, Nydam, Grant, and Overton, 2010 Cornell Nutrition Conference
There is a positive correlation between the time it takes to approach the bunk following FD and daily NEFA (r=0.30) and glucose (r=0.24) concentration (P≤0.02). Pattern of feeding activity • In the overstocked group fewer cows were at the feed bunk following fresh feed delivery while more cows were at the bunk at night % of cows at the feed bunk Feed Delivery Hour of the Day Huzzey, Nydam, Grant, and Overton, 2010 Cornell Nutrition Conference
DMI & feeding time Feeding time was not different between overstocked and control groups (242 vs. 241 min/cow/d) • Feeding rate was greater in overstocked cows • Cows in the overstocked group had a greater DMI (33 vs 31 lb/d) DMI (kg/cow) Treatment Day Huzzey, Nydam, Grant, and Overton, 2010 Cornell Nutrition Conference
Daily metabolite concentrations NEFA Glucose uEQ/L mg/dL trt day Insulin Fecal Cortisol Met. uIU/mL ng/g fecal DM Huzzey, Nydam, Grant, and Overton, 2010 Cornell Nutrition Conference
Challenges with assessing energy metabolism and inflammation-related opportunities in transition cows • Most of dairy industry works on averages • Challenges related to energy/grouping mgt/nonnutritional factors cause increases in variation in DMI/performance • Almost impossible to detect some of these on farms • Potential tools for use in monitoring variation in transition cow management • NEFA (best marker for negative energy balance) • BHB (“gold standard” blood ketone) • Haptoglobin and/or fecal cortisol? (not ready for prime time) • Variation in early lactation milk yield
Question: Which of the following do you think are the most important effects/associations of elevated NEFA and/or BHB in transition cows? • Increased incidence of health disorders • Poorer reproductive performance • Decreased milk production
Herd-level impacts of elevated NEFA/BHB *15% of 15 = 2-3 animals Ospina et al., 2010
Approach for monitoring energy-related blood analytes in transition cows • Sample size: • >12 cows • Cows to sample • Pre-partum: 14 to 2 days before calving • Post-partum: 3 to 14 DIM • Sample to take • Serum (red top tubes) • Don’t shake, keep cool • What to do with sample? • BHB: Lab or Precision Extra Meter • NEFA: Lab • What to do with results • Interpret % above cut-point • More than 15% above cut-point indicates herd-level problem
Interpretation of metabolites to assess herd-level opportunities • Scenario 1 – High prepartum NEFA, High postpartum NEFA and/or BHB • Likely starting with low DMI in close-up cows • Too low energy in prefresh diet, facility and/or management issues (grouping, stocking, heat stress)? • Scenario 2 – High prepartum NEFA, low postpartum NEFA and/or BHB • Likely low DMI in close-up cows • Are you sampling the survivors in the fresh pen? • Is the herd outmanaging or putting band-aids on fresh cow issues? • Scenario 3 – Low prepartum NEFA, high postpartum NEFA and/or BHB • Is herd overfeeding energy either far-off or close-up? • Diet or facility/management issues specific to maternity/fresh cow group
Ways to evaluate variation in early lactation performance • Milk yield/ME projection and index of variability at test days following calving • Standard deviation • +/- 1 SD accounts for 67% of observations • Coefficient of variation (CV) • SD divided by mean • 1st Test day milk yield (n=48) • Mean SD = 25.2 lb (range 10.5 to 30.4) • Mean CV = 0.35 (range 0.25 to 0.62) • 1st ME projected milk yield (n=48) • Mean SD = 5166 lbs (range 4192 to 6822) • Mean CV = 0.20 (range 0.16 to 0.24)
Herd-level pregnancy rate vs. CV (index of variation) of ME milk yield projected at the first test day after calving
17/20 prepartum animals > 0.3 mEq/L NEFA!! 5/20 postpartum animals > 0.7 mEq/L NEFA 5/20 postpartum animals > 12 mg/dL BHBA
Monthly snapshot of herd milk production at test day 120 100 80 60 40 Days in milk at test day
The outcome challenge • High milk production • Maintain/minimize loss of BCS • Low incidence of metabolic disorders • Minimize loss of immunocompetence • Control/decrease days to first ovulation and maintain/enhance fertility • Make $$
The transition management challenge • Putting systems into place (nutritional strategies, facilities, grouping strategies) that decrease individual variability or counter inherent animal to animal variation • Remember, it’s about milk and reproductive performance; disorders/disease should not drive the transition opportunity discussion