Instituto Nacional de Investigaciones Agropecuarias FCAV

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Browsing Instituto Nacional de Investigaciones Agropecuarias FCAV by Author "Johanny Pérez"

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    Association between prepartum body condition score and prepartum and postpartum dry matter intake and energy balance in multiparous Holstein cows
    (2024-06-26) Johanny Pérez
    The objectives of this retrospective observational study were to investigate the association between BCS at 21 d before calving with prepartum and postpartum DMI, energy balance (EB), and milk yield. Data from 427 multigravid cows from 11 different experiments conducted at the University of Florida (Gainesville, FL) were used. Cows were classified according to their BCS at 21 d before calving as fat (BCS ≥ 4.00; n = 83), moderate (BCS = 3.25–3.75; n = 287), and thin (BCS ≤ 3.00; n = 57). Daily DMI from −21 to −1 and from +1 to +28 DIM was individually recorded. Energy balance was calculated as the difference between net energy for lactation consumed and required. Dry matter intake in fat cows was lower than that in moderate and thin cows both prepartum (fat = 9.97 ± 0.21, moderate = 11.15 ± 0.14, and thin = 11.92 ± 0.22 kg/d) and postpartum (fat = 14.35 ± 0.49, moderate = 15.47 ± 0.38, and thin = 16.09 ± 0.47 kg/d). Dry matter intake was also lower for moderate cows compared with thin cows prepartum, but not postpartum. Energy balance in fat cows was lower than in moderate and thin cows both prepartum (fat = −4.16 ± 0.61, moderate = −1.20 ± 0.56, and thin = 0.88 ± 0.62 Mcal/d) and postpartum (fat = −12.77 ± 0.50, moderate = −10.13 ± 0.29, and thin = −6.14 ± 0.51 Mcal/d). Energy balance was also lower for moderate cows compared with thin cows both prepartum and postpartum. There was a quadratic association between BCS at 21 d before calving and milk yield. Increasing BCS from 2.5 to 3.5 was associated with an increase in daily milk yield of 6.0 kg and 28 d cumulative milk of 147 kg. Increasing BCS from 3.5 to 4.5 was associated with a decrease in daily milk yield of 4.4 kg and 28 d cumulative milk of 116 kg. In summary, a moderate BCS at 21 d before calving was associated with intermediate DMI and EB pre- and postpartum but greater milk yield compared with thinner and fatter cows. Our findings indicate that a moderate BCS is ideal for ensuring a successful lactation.
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    Association between prepartum body condition score and prepartum and postpartum dry matter intake and energy balance in multiparous Holstein cows
    (2024) Johanny Pérez
    The objectives of this retrospective observational study were to investigate the association between body condition score (BCS) at 21 d before calving with prepartum and postpartum dry matter intake (DMI), energy balance (EB), and milk yield. Data from 427 multigravid cows from 11 different experiments conducted at the University of Florida were used. Cows were classified according to their BCS at 21 d before calving as FAT (BCS ≥4.00; n = 83), MOD (BCS 3.25 to 3.75; n = 287), and THIN (BCS ≤3.00; n = 57). Daily DMI from −21 to −1 and from +1 to +28 DIM was individually recorded. Energy balance was calculated as the difference between net energy for lactation consumed and required. Dry matter intake in FAT cows was lesser than in MOD and THIN cows both prepartum (FAT = 9.97 ± 0.21, MOD = 11.15 ± 0.14, THIN = 11.92 ± 0.22 kg/d) and postpartum (FAT = 14.35 ± 0.49, MOD = 15.47 ± 0.38, THIN = 16.09 ± 0.47 kg/d). Dry matter intake was also lesser for MOD cows compared with THIN cows prepartum, but not postpartum. Energy balance in FAT cows was lesser than in MOD and THIN cows both prepartum (FAT = −4.16 ± 0.61, MOD = −1.20 ± 0.56, THIN = 0.88 ± 0.62 Mcal/d) and postpartum (FAT = −12.77 ± 0.50, MOD = −10.13 ± 0.29, THIN = −6.14 ± 0.51 Mcal/d). Energy balance was also lesser for MOD cows compared with THIN cows both prepartum and postpartum. There was a quadratic association between BCS at 21 d before calving and milk yield. Increasing BCS from 2.5 to 3.5 was associated with an increase in daily milk yield of 6.0 kg and 28 d cumulative milk of 147 kg. Increasing BCS from 3.5 to 4.5 was associated with a decrease in daily milk yield of 4.4 kg and 28 d cumulative milk of 116 kg. In summary, a moderated BCS at 21 d before calving was associated with intermediate DMI and EB pre- and postpartum but greater milk yield compared with thinner and fatter cows. Our findings indicate that a moderated BCS is ideal for ensuring a successful lactation.
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    Investigating the Use of Dry Matter Intake and Energy Balance Prepartum as Predictors of Digestive Disorders Postpartum
    (2021-09-15) Johanny Pérez
    One objective was to evaluate the association of dry matter intake as a percentage of body weight (DMI%BW) and energy balance (EB) prepartum and postpartum, and energy-corrected milk (ECM) postpatum with digestive disorders postpartum. For this, ANOVA was used, and DMI%BW, EB, and ECM were the outcome variables, and left displaced abomasum (LDA), indigestion, and other digestive disorders (ODDZ) were the explanatory variables. The main objective was to evaluate prepartum DMI%BW and EB as predictors of digestive disorders. For this, logistic regression was used, and LDA, indigestion, and ODDZ were the outcome variables and DMI%BW and EB were the explanatory variables. Data from 689 cows from 11 experiments were compiled. Left displaced abomasum was not associated with prepartum DMI%BW or EB. Postpartum data were normalized to the day of the event (day 0). Cows that developed LDA had lesser postpartum DMI%BW on days −24, −23, −12, −7 to 0 and from days 1 to 8, 10 to 12, and 14 and 16, lesser postpartum EB from days −7 to −5, −3 to 0, and 12, and lesser postpartum energy-corrected milk on days −19, −2, −1, 0, 7, 9, 10, 15, and 17 relative to diagnosis than cows without LDA. Cows that developed indigestion had lesser prepartum DMI%BW and EB than cows without indigestion, and lesser postpartum DMI%BW on days −24, −1, 0, 1, and 2, and greater DMI%BW on day 26, lesser ECM on days −24, −2, −1, 0, 1, and 2 relative to diagnosis. Postpartum EB was not associated with indigestion postpartum. Cows that developed ODDZ had lesser prepartum DMI%BW on day −8 and from days −5 to −2, lesser prepartum EB on day −8 and from days −5 to −2, and lesser postpartum DMI%BW than cows without ODDZ. Each 0.1 percentage point decrease in the average DMI%BW and each Mcal decrease in the average EB in the last 3 days prepartum increased the odds of having indigestion by 9% each. Cutoffs for DMI%BW and EB during the last 3 days prepartum to predict indigestion were established and were ≤1.3%/day and ≤0.68 Mcal/day, respectively. In summary, measures of prepartum DMI%BW and EB were associated with indigestion and ODDZ postpartum and were predictors of indigestion postpartum, although the effect sizes were small.
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    (Proyecto) Estudio económico de la endometritis en hatos lecheros.
    (2026) Johanny Pérez
    La endometritis se define como una secreción vaginal que ocurre después de los 21 días postparto en vacas lecheras. Esta enfermedad causa efectos negativos directos e indirectos a la producción de las vacas lecheras. El objetivo de este estudio es estimar el costo de la endometritis en hatos lecheros. En otro estudio se recopilaron datos de 11,733 vacas lecheras de 16 granjas diferentes ubicadas en 4 regiones diferentes de la en los Estados Unidos de América durante 305 días de lactación. Resultados continuos como producción de leche en 305 días de lactación, ventas de leche (USD$/vaca), ventas de vacas (USD$/vaca), costos de tratamiento de endometritis (USD$/vaca), costos de reemplazo (USD$/vaca), costos de reproducción (USD$/vaca), los costos de alimentación (USD$/vaca) y la ganancia por vaca (USD$/vaca) se analizarán utilizando el procedimiento MIXED de SAS para modelos mixtos. Se analizarán resultados dicotómicos como embarazo y sacrificio ocurridos durante los 305 días de lactación utilizando el procedimiento GLIMMIX de SAS. Los modelos incluíran los efectos fijos: endometritis, paridad y la interacción entre la endometritis y la paridad, y el hato será tratado como efecto aleatorio. Las variables se considerarán significativas cuando P ≤ 0.05. El costo de la endometritis se calculará restando la ganancia de las vacas con endometritis de la ganancia de las vacas sin endometritis. Se realizará un análisis estocástico con 10,000 iteraciones utilizando los resultados observados de cada grupo. En conclusión, es importante saber el impacto económico que puede causar la a endometritis a los hatos lecheros.
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    (Proyecto) Relación de consumo de materia seca con enfermedades digestivas durante el pre y el postparto en vacas lecheras.
    (2026) Johanny Pérez
    El consumo de materia seca (CMS) y el balance de energía neta (BEN) durante el período de transición puede que tenga un importante rol en el desarrollo de enfermedades; por tanto, podría ser utilizado como una herramienta para predecir enfermedades que ocurren durante el postparto en vacas lecheras. El objetivo principal de este proyecto será determinar la relación entre el CMS ajustado por el porcentaje del peso corporal y el BEN durante el preparto (21 d antes del parto) y durante el post-posparto (28 d después del parto) con trastornos digestivos en vacas lecheras. Como objetivo secundario se evaluará el CMS durante el preparto y el BEN como predictores de trastornos digestivos. Se compilarán datos de 476 vacas de 9 experimentos que han sido realizados en la Universidad de Florida. En estos experimentos el CMS fue medido diariamente por cada vaca durante los períodos de preparto y de postparto. El BEN diario será calculado en base al CMS diario y al peso corporal durante el período de transición. Los datos para evaluar el primer objetivo serán analizados con ANOVA para modelos mixtos y para el segundo objetivo con modelos lineales generalizados mixtos utilizando el programa estadístico de SAS (versión 9.4). El CMS y el BEN serán las variables independientes y los trastornos digestivos serán las variables dependientes. Para evaluar el objetivo secundario, los trastornos digestivos serán las variables independientes y El CMS y el BEN serán las variables dependientes. En resumen, las medidas de prepartum DMI podrían estar asociadas y pueden predecir vacas con trastornos digestivos postparto.
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    The economic impact of purulent vaginal discharge in dairy herds within a s ingle lactation
    (2024) Johanny Pérez
    The goal of this study was to calculate the cost of purulent vaginal discharge (PVD) in dairy cows. The dataset included 11,051 cows from 16 dairy herds located in 4 regions of the United States. Purulent vaginal discharge was characterized as a mucopurulent, purulent, or red dish-brownish vaginal discharge collected at 28 ± 7 DIM. Gross profit was calculated as the difference between incomes and expenses, and the cost of PVD was calculated by subtracting the gross profit of cows with PVD from the gross profit of cows without PVD. Continuous outcomes such as milk production (kg/cow), milk sales ($/cow), cow sales ($/cow), feed costs ($/cow), repro ductive management costs ($/cow), replacement costs ($/ cow), and gross profit ($/cow) were analyzed using lin ear mixed effects models. Pregnancy and culling by 305 DIM were analyzed by generalized linear mixed effects models using logistic regression. Models included the fixed effects of PVD, metritis, parity, region, season of calving, and morbidity in the first 60 DIM, as well as the interactions between PVD and metritis, PVD and parity group, and PVD and morbidity. Farm and the interaction between PVD and farm were considered random effects in all the statistical models. A stochastic analysis was conducted using 10,000 iterations with varying relevant inputs. Cows with PVD produced less milk (9,753.2 ± 333.6 vs. 9,994.6 ± 330.9 kg/cow), were less likely to be pregnant (70.7 ± 1.7% vs. 78.9 ± 1.2%), and were more likely to be culled by 305 DIM (34.6 ± 1.7% vs. 27.2 ± 1.3%) compared with cows without PVD. Consequently, milk sales (4,744.7 ± 162.3 vs. 4,862.1 ± 161.0 $/cow) and residual cow value (1,079.6 ± 23.0 vs. 1,179.3 ± 20.3 $/cow) were lesser for cows with PVD. Replacement (639.4 ± 26.4 vs. 526.0 ± 23.4 $/cow) and reproductive management costs (76.3 ± 2.5 vs. 69.0 ± 2.4 $/cow) were greater for cows with PVD. The mean cost of PVD was $202. The stochastic analysis also showed a mean cost of $202, ranging from $152 to $265. The robust dataset and the stochastic analysis strengthen both the external and internal validity of our findings, offering a deeper understanding of the economic consequences of PVD. In conclusion, PVD resulted in large economic losses to dairy herds by being associated with decreased milk yield, impaired reproduction, and greater culling.