Effect of Body Condition Score at Calving on Performance, Some Blood Parameters, and Milk Fatty Acid Composition in Dairy Cows

Effect of body condition score at calving and of change in body condition score on productive and reproductive performance, on lactation curve parameters, and on postpartum disease occurrence was investigated in 213 Italian Holstein-Friesian cows. Plasma FFA, glucose, and insulin concentrations and milk fatty acid composition were analyzed in 15 cows. The cows calving at highest body condition score lost more subcutaneous fat; condition score change did not exceed 1.05 units. Change in body condition score was positively associated with peak and total milk production. Occurrence of retained placenta was not related to the content of fat stores at calving. Glucose concentrations were relatively constant, FFA concentrations were highest, and insulin concentrations were lower in cows calving at the highest body condition score. Milk fatty acid composition reflected the different utilization of body fat stores

Heritabilities and Genetic Correlations of Body Condition Score and Muscularity with Productive Traits and their Trend Functions in Italian Simmental Cattle

With the aim to study the genetics of energy and muscle balance in the Italian Simmental breed, the objectives of this study were: i) the estimation of the genetic parameters for body condition score (BCS) and muscularity (MU) score; ii) the estimation of genetic correlations of BCS and MU with productive traits; iii) the estimation of the expected pattern of BCS and MU over lactation. A total of 47,839 records of first-parity lactating cows, collected from 1999 to 2007 in 2794 herds, were used. Two-trait animal models were analyzed using restricted maximum likelihood (REML) procedures to estimate (co)variance components. The expected patterns of BCS and MU along the lactation of first parity cows were estimated from the solutions of DIM fixed effect obtained from an univariate mixed model for both the traits. The heritability estimated was 0.18 for BCS, 0.38 for MU, and ranged from 0.13 to 0.18 for yield traits. The genetic correlations between BCS, MU and yield traits were negative (-0.17 to -0.63). The genetic correlation between BCS and MU was strongly positive (0.88), indicating that cows that genetically tend to have high BCS are more likely to have high values of MU. The genetic parameters estimated suggested that selection for BCS and MU in dual purpose breeds may be possible, and BCS may indirectly improve MU. The expected patterns for BCS and MU showed the trend of these two traits along the lactation and can help farmers in planning the best management of the lactating cows

Interfamiliar specific fertility in Italian Brown Swiss cattle

The aim of this study is to evaluate the effects of interaction between sire of cow and service sire on the success/unsuccess of inseminations. Data from insemination events of Italian Brown Swiss cows collected from January 1993 through August 2007 were restricted to repeat breeder cows. A cluster analysis was carried out to group herds with very few observations in clusters with at least 15 observations. The edited data set included 102,710 services of 10,708 cows, daughters of 1,716 sires and mated to 3,108 service sires. The success or unsuccess at each insemination was evaluated by a linear mixed model including the fixed effects of herd-year interaction, month of insemination, age, and the random effects of sire service-sire of cow interaction and residual. The distribution of bull combination estimates was bimodal. When the tails of distribution (best and worst 5% of estimates) were considered, 271 service sires were included in both tails. Results suggest that major gene can affect the survival of embryos and that positive or negative interactions between paternal and maternal genotype can affect this reproductive trait

Comparison of morphological traits of teats in three dairy breeds

Entre agosto 2003 y febrero del año 2004 se evaluaron las características de los pezones en 1263 vacas Carora, 403 Holstein y 118 Jersey ubicadas en Venezuela. La forma del pezón fue clasificada como embudo, cilíndrico y botella, mientras que la punta del pezón se clasificó de la siguiente manera: puntiaguda, redondeada, plana, disco, invertido y prolapsada. Se midió también, el largo y para cada pezón. El objetivo de este trabajo fue evaluar el efecto raza sobre las características morfológicas de los pezones. El largo y diámetro fueron analizados con un modelo mixto incluyendo como efectos fijos la raza, edad de la vaca, la interacción rebaño - año de nacimiento y el efecto aleatorio de la vaca dentro del rebaño. Los tipos de pezones y las puntas de los mismos se analizaron por medio del SAS versión 8,0 con el Proc. Freq y el Proc. Univaríate. Para la asociación de las características de los pezones con las razas se utilizó la prueba de Ji cuadrado (x²). La raza Carora mostró un efecto significativo sobre el largo y diámetro del pezón: el largo estimado fue 5,9; 5,4 y 5,3 cm y el diámetro estimado fue 2,3; 2,2 y 2,1 para Carora, Holstein y Jersey, respectivamente. Ningún efecto significativo de raza fue encontrado para la forma y tipo punta de pezón, pero hubo predominio en las tres razas de la forma redondeada, seguido de los puntiagudos.393 - 400BimestralMorphological traits of teats and teat-end were evaluated from August 2003 to February 2004 in 1263 Carora, 403 Holstein and 118 Jersey cows reared in Venezuela. Teat type was classified as funnel, cylindrical and bottle whereas teat-end was classified as pointed, round, flat, disk, funnel shape and prolapsed. Also, the length and diameter were measured for each teat. The aim of this work was to evaluate the morphological effect of breed on the teat treats. Teat length and diameter were analyzed by a mixed model including the fixed effects of breed, age of cows, herd- birth year interaction and the random effect of the cow within herd. Teats and teat-end types were analyzed by SAS version 8.0 with the Proc. Freq and Proc. Univaríate. In order to associate the teat traits with the breed was used Chi square (x²). Carora breed showed a significant effect on teat length and diameter: the estimated teat length was 5.9, 5.4 and 5.3 cm and the estimated teat diameter was 2.3, 2.2 and 2.1 for Carora, Holstein and Jersey, respectively. Teat length and diameter increased as the age increases. No significant effect of breed was found for teat and teat-end type but in the three breeds there was predominance of round and pointed shape

Genetic parameters of morphological traits of Carora cattle

Dieciséis (16) características de conformación de la raza Carora, fueron estudiadas en 3867 vacas. Los parámetros genéticos de las mismas se analizaron usando el modelo animal para características múltiples. Los efectos fijos considerados fueron: interacción rebaño-año, mes de evaluación, edad, estado de la lactancia y el clasificador del rebaño. Los parámetros genéticos se obtuvieron del REML para estimar los componentes de la (co)variancia. Las heredabilidades más altas se obtuvieron en la alzada (0,47) y profundidad corporal (0,27), mientras que el valor más bajo fue observado para el ángulo de la pezuña (0,03). Las características de la ubre mostraron bajo índice de herencia, estimándose un rango que iba de 0,06 para la inserción de la ubre trasera, a 0,13 para el nivel del piso de la ubre. Las correlaciones genéticas entre la alzada, profundidad corporal y ancho de la grupa fueron altas, con un rango de 0,76 a 0,86. Estimaciones altas se encontraron en la separación de pezones (0,16) y largo del pezón (0,26). La inserción delantera de la ubre fue positivamente asociada con la inserción de la ubre trasera (0,46), profundidad corporal (0,53), separación de pezones (0,17) y largo de pezones. (0,18), mientras correlación negativa se observó en el nivel del piso la ubre. Otras estimaciones negativas de correlación genética, se encontraron entre el nivel de grupa (-0,45), en las patas traseras vistas de atrás (-0,50), el nivel del piso de la ubre (-0,68) y la angulosidad. A su vez, la angulosidad fue positivamente asociada a la inserción trasera de ubre (0,62). Pequeñas correlaciones fueron estimadas entre el ángulo de la pezuña y la mayoría de las características evaluadas. La correlación genética negativa entre el desarrollo corporal y las características de la ubre, sugirieron que la selección por incremento de tamaño corporal no mejora la conformación de la ubre. Por lo tanto la selección debería estar orientada hacia animales de talla mediana con características lecheras.58 - [email protected] (16) morphological traits from 3867 Carora cows in Venezuela were studied. Genetic parameters were analyzed using a multiple trait animal model. Fixed effects of herd- year of evaluation interaction, month evaluation, age, stage of lactation classifier, within herd were considered, genetic parameters were obtained from REML estimates of covariance components. The highest heritability was found for stature (0.47) and for body depth (0.27), whereas the lowest values were found for foot angle (0.03). Udder traits showed low heritability estimates ranging from 0.06 for rear with to 0.13 for de udder balance. Higher estimations were found for tea placement side (0.16) and teat length (0.26). Genetic correlations among stature, body depth, strength and rump width were high and ranged from 0.76 to 0.86. Fore udder attachment was positively associated with rear udder height (0.46), udder depth (0.53), teat placement (0.17) and length (0.18) while a negative correlations with udder balance (-.028). Negative estimates genetic correlations were found between rump angle (-0.45), rear-legs rear view (-0.50), udder balance (-0.68), udder support (-0.32) y la angularity. Angularity was positively associated with rear udder height 0.62. Small correlations were estimated between foot angle and most traits. Negative genetic correlations between body development and udder traits suggested that selection to increase body size could not improve the udder conformation.. Selection should be oriented towards animals of medium size dairy characteristics