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R F Veerkamp - One of the best experts on this subject based on the ideXlab platform.

  • Leptin concentrations in relation to Energy Balance, milk yield, intake, live weight, and estrus in dairy cows
    Journal of Dairy Science, 2003
    Co-Authors: S.c. Liefers, R F Veerkamp, M.f.w. Te Pas, Carole Delavaud, Yves Chilliard, T. Van Der Lende
    Abstract:

    The objective of this study was to describe fluctuations in leptin concentrations during late pregnancy and lactation and to investigate how those fluctuations are related to Energy Balance, milk yield, milk components, dry matter intake, live weight, first postpartum luteal activity, and first observed estrus during lactation. Live weight, dry matter intake, Energy Balance, and milk yield were measured weekly on 304 primiparous Holstein cows for the first 80 d of lactation. The first postpartum luteal activity was determined by measuring milk progesterone, and independently, first observed estrus. For measuring leptin concentrations from 30 d before until 80 d after calving, blood samples were taken at 2-wk intervals at a fixed time of the day after milking but before feeding. Leptin concentrations were high during pregnancy and declined to a nadir at parturition. It seems that leptin concentrations reflect the state of Energy Balance during lactation; plasma leptin concentrations were lower in cows with a mean negative Energy Balance during lactation. Those cows usually produced more milk, consumed less feed, and had a lower live weight compared with cows having a mean positive Energy Balance. The recovery of leptin concentrations from the leptin nadir at parturition seemed to depend on the extent and duration of the negative Energy Balance, thus probably on the amount of fat that was re-accumulated. Although there was lack of a relationship between leptin and first postpartum luteal activity, higher leptin concentrations associated with shorter intervals to first observed estrus might indicate a relationship between leptin and expression of estrus.

  • Energy Balance of dairy cattle in relation to milk production variables and fertility
    Journal of Dairy Science, 2000
    Co-Authors: M J De Vries, R F Veerkamp
    Abstract:

    Abstract Variables derived from milk yield records were investigated to find an easy to measure and readily available indicator of the Energy Balance status of a lactating cow. Weekly Energy Balances during the first 180 d in milk (DIM) were calculated from weekly yield, live weight, and Energy intake records for 470 first lactation heifers. The Energy Balance curve for each cow was estimated using a random regression model. From each curve, three measures were calculated to describe the Energy Balance status: 1) total Energy deficit in early lactation, 2) interval for return to positive Energy Balance, and 3) lowest value (nadir) for Energy Balance. Mean Energy deficit per lactation was 776.8 MJ of NE L /d, interval for return to positive Energy Balance was 41.47 d, and nadir was –33.72 MJ of NE L /d. Regression analysis to relate these variables to interval to start of luteal activity (measured using progesterone profiles) showed that a low nadir of Energy Balance was related to delayed resumption of luteal activity. In general, a 10 MJ of NE L /d lower nadir of Energy Balance corresponded to a delay of ovulation of 1.25 d. A relatively strong decrease in fat percentage during early lactation was significantly correlated with lower nadir of Energy Balance, larger Energy deficit, and later return to positive Energy Balance. The maximal correlation was between nadir of Energy Balance and a decrease of milk fat percentage. This correlation remained above 0.60 throughout the first 26 DIM but dropped to 0.14 at 180 DIM. Large decreases in milk fat percentage were related to high initial fat percentages at the start of lactation and slightly lower fat percentages later during lactation. Hence, we concluded that a decrease in fat percentage during early lactation might serve as an indicator of Energy Balance.

  • Energy Balance of dairy cattle in relation to milk production variables and fertility
    Journal of Dairy Science, 2000
    Co-Authors: M J De Vries, R F Veerkamp
    Abstract:

    Variables derived from milk yield records were investigated to find an easy to measure and readily available indicator of the Energy Balance status of a lactating cow. Weekly Energy Balances during the first 180 d in milk (DIM) were calculated from weekly yield, live weight, and Energy intake records for 470 first lactation heifers. The Energy Balance curve for each cow was estimated using a random regression model. From each curve, three measures were calculated to describe the Energy Balance status: 1) total Energy deficit in early lactation, 2) interval for return to positive Energy Balance, and 3) lowest value (nadir) for Energy Balance. Mean Energy deficit per lactation was 776.8 MJ of NE(L)/d, interval for return to positive Energy Balance was 41.47 d, and nadir was -33.72 MJ of NE(L)/d. Regression analysis to relate these variables to interval to start of luteal activity (measured using progesterone profiles) showed that a low nadir of Energy Balance was related to delayed resumption of luteal activity. In general, a 10 MJ of NE(L)/d lower nadir of Energy Balance corresponded to a delay of ovulation of 1.25 d. A relatively strong decrease in fat percentage during early lactation was significantly correlated with lower nadir of Energy Balance, larger Energy deficit, and later return to positive Energy Balance. The maximal correlation was between nadir of Energy Balance and a decrease of milk fat percentage. This correlation remained above 0.60 throughout the first 26 DIM but dropped to 0.14 at 180 DIM. Large decreases in milk fat percentage were related to high initial fat percentages at the start of lactation and slightly lower fat percentages later during lactation. Hence, we concluded that a decrease in fat percentage during early lactation might serve as an indicator of Energy Balance.

M J De Vries - One of the best experts on this subject based on the ideXlab platform.

  • Energy Balance of dairy cattle in relation to milk production variables and fertility
    Journal of Dairy Science, 2000
    Co-Authors: M J De Vries, R F Veerkamp
    Abstract:

    Abstract Variables derived from milk yield records were investigated to find an easy to measure and readily available indicator of the Energy Balance status of a lactating cow. Weekly Energy Balances during the first 180 d in milk (DIM) were calculated from weekly yield, live weight, and Energy intake records for 470 first lactation heifers. The Energy Balance curve for each cow was estimated using a random regression model. From each curve, three measures were calculated to describe the Energy Balance status: 1) total Energy deficit in early lactation, 2) interval for return to positive Energy Balance, and 3) lowest value (nadir) for Energy Balance. Mean Energy deficit per lactation was 776.8 MJ of NE L /d, interval for return to positive Energy Balance was 41.47 d, and nadir was –33.72 MJ of NE L /d. Regression analysis to relate these variables to interval to start of luteal activity (measured using progesterone profiles) showed that a low nadir of Energy Balance was related to delayed resumption of luteal activity. In general, a 10 MJ of NE L /d lower nadir of Energy Balance corresponded to a delay of ovulation of 1.25 d. A relatively strong decrease in fat percentage during early lactation was significantly correlated with lower nadir of Energy Balance, larger Energy deficit, and later return to positive Energy Balance. The maximal correlation was between nadir of Energy Balance and a decrease of milk fat percentage. This correlation remained above 0.60 throughout the first 26 DIM but dropped to 0.14 at 180 DIM. Large decreases in milk fat percentage were related to high initial fat percentages at the start of lactation and slightly lower fat percentages later during lactation. Hence, we concluded that a decrease in fat percentage during early lactation might serve as an indicator of Energy Balance.

  • Energy Balance of dairy cattle in relation to milk production variables and fertility
    Journal of Dairy Science, 2000
    Co-Authors: M J De Vries, R F Veerkamp
    Abstract:

    Variables derived from milk yield records were investigated to find an easy to measure and readily available indicator of the Energy Balance status of a lactating cow. Weekly Energy Balances during the first 180 d in milk (DIM) were calculated from weekly yield, live weight, and Energy intake records for 470 first lactation heifers. The Energy Balance curve for each cow was estimated using a random regression model. From each curve, three measures were calculated to describe the Energy Balance status: 1) total Energy deficit in early lactation, 2) interval for return to positive Energy Balance, and 3) lowest value (nadir) for Energy Balance. Mean Energy deficit per lactation was 776.8 MJ of NE(L)/d, interval for return to positive Energy Balance was 41.47 d, and nadir was -33.72 MJ of NE(L)/d. Regression analysis to relate these variables to interval to start of luteal activity (measured using progesterone profiles) showed that a low nadir of Energy Balance was related to delayed resumption of luteal activity. In general, a 10 MJ of NE(L)/d lower nadir of Energy Balance corresponded to a delay of ovulation of 1.25 d. A relatively strong decrease in fat percentage during early lactation was significantly correlated with lower nadir of Energy Balance, larger Energy deficit, and later return to positive Energy Balance. The maximal correlation was between nadir of Energy Balance and a decrease of milk fat percentage. This correlation remained above 0.60 throughout the first 26 DIM but dropped to 0.14 at 180 DIM. Large decreases in milk fat percentage were related to high initial fat percentages at the start of lactation and slightly lower fat percentages later during lactation. Hence, we concluded that a decrease in fat percentage during early lactation might serve as an indicator of Energy Balance.

Vincenzo Di Marzo - One of the best experts on this subject based on the ideXlab platform.

  • endocannabinoid control of food intake and Energy Balance
    Nature Neuroscience, 2005
    Co-Authors: Vincenzo Di Marzo, Isabelle Matias
    Abstract:

    Marijuana and its major psychotropic component, Δ9-tetrahydrocannabinol, stimulate appetite and increase body weight in wasting syndromes, suggesting that the CB1 cannabinoid receptor and its endogenous ligands, the endocannabinoids, are involved in controlling Energy Balance. The endocannabinoid system controls food intake via both central and peripheral mechanisms, and it may also stimulate lipogenesis and fat accumulation. Here we discuss the multifaceted regulation of Energy homeostasis by endocannabinoids, together with its applications to the treatment of eating disorders and metabolic syndromes.

  • endocannabinoid control of food intake and Energy Balance
    Nature Neuroscience, 2005
    Co-Authors: Vincenzo Di Marzo, Isabel Matias
    Abstract:

    Marijuana and its major psychotropic component, Delta(9)-tetrahydrocannabinol, stimulate appetite and increase body weight in wasting syndromes, suggesting that the CB(1) cannabinoid receptor and its endogenous ligands, the endocannabinoids, are involved in controlling Energy Balance. The endocannabinoid system controls food intake via both central and peripheral mechanisms, and it may also stimulate lipogenesis and fat accumulation. Here we discuss the multifaceted regulation of Energy homeostasis by endocannabinoids, together with its applications to the treatment of eating disorders and metabolic syndromes.

L R Schaeffer - One of the best experts on this subject based on the ideXlab platform.

  • relationships between Energy Balance and health traits of dairy cattle in early lactation
    Journal of Dairy Science, 2000
    Co-Authors: B L Collard, P J Boettcher, Jack C M Dekkers, D Petitclerc, L R Schaeffer
    Abstract:

    The objective of the study was to calculate phenotypic relationships between Energy Balance in early lactation and health and reproduction in that lactation. Data were 26,701 daily records of dry matter intake and milk production, periodic measures of milk composition and body weight, and all health and reproductive information from 140 multiparous Holstein cows. Daily Energy Balance was calculated by multiplying feed intake by the concentration of Energy of the ration and subtracting the amount of Energy required for maintenance (based on parity and body weight) and for milk production (based on yield and concentrations of fat, protein, and lactose). Six measures of Energy Balance were defined: mean daily Energy Balance during the first 20, 50, and 100 d of lactation; minimum daily Energy Balance; days in negative Energy Balance; and total Energy deficit. Measures of health were the numbers of occurrences of each of the following during lactation: all udder problems, mastitis, all locomotive problems, laminitis, digestive problems, and reproductive problems. Reproductive traits were the number of days to first observed estrus and number of inseminations. Several significant relationships between Energy Balance and health were observed. Increased digestive and locomotive problems were associated with longer and more extreme periods of negative Energy Balance.

Isabelle Matias - One of the best experts on this subject based on the ideXlab platform.

  • endocannabinoid control of food intake and Energy Balance
    Nature Neuroscience, 2005
    Co-Authors: Vincenzo Di Marzo, Isabelle Matias
    Abstract:

    Marijuana and its major psychotropic component, Δ9-tetrahydrocannabinol, stimulate appetite and increase body weight in wasting syndromes, suggesting that the CB1 cannabinoid receptor and its endogenous ligands, the endocannabinoids, are involved in controlling Energy Balance. The endocannabinoid system controls food intake via both central and peripheral mechanisms, and it may also stimulate lipogenesis and fat accumulation. Here we discuss the multifaceted regulation of Energy homeostasis by endocannabinoids, together with its applications to the treatment of eating disorders and metabolic syndromes.