Browsing by Author "Joy, Margalida"
Now showing 1 - 10 of 10
Results Per Page
Sort Options
- Assessment of goat fat depots using ultrasound technology and multiple multivariate prediction modelsPublication . Peres, António M.; Dias, L.G.; Joy, Margalida; Teixeira, AlfredoAssessment of fat depots for several goat body parts is an expensive and time-consuming task requiring a trained technician. Therefore, the establishment of models to predict fat depots based on data requiring simpler and easier procedures, such as ultrasound measurements, that could be carried out in vivo, would be a major advantage. An interesting alternative to the use of multiple linear regression models is the use of partial least squares or artificial neural network models because they allow the establishment of one model to simultaneously predict different fat depots of interest. In this work, the applicability of these models to simultaneously predict 7 goat fat depots (subcutaneous fat, intermuscular fat, total carcass fat, omental fat, kidney and pelvic fat, mesenteric fat, and total body fat) was investigated. Although satisfactory correlation and prediction results were obtained using the multiple partial least squares model (cross-verification and validation R2 and standard prediction error values between 0.66 and 0.98 and 247 and 2,168, respectively), the best global correlation and prediction performances were achieved with the multiple radial basis function artificial neural network (verification and validation R2 and standard prediction error values between 0.82 and 0.96 and 304 and 1,707, respectively). These 2 multiple models allowed correlating and predicting simultaneously the 7 goat fat depots based on the goat BW and on only 2 ultrasonic measures (lumbar subcutaneous fat between fifth and sixth vertebrae and the fat depth at the third sternebra). Moreover, both multiple models showed better results compared with those obtained with multiple linear regression models proposed in previous work.
- Atlas de disección de la canal de los ruminantesPublication . Panea, Begoña; Ripoll, Guillermo; Alberti, P.; Joy, Margalida; Teixeira, AlfredoSe presenta un atlas para la disección de la canal de los rumiantes. El atlas se estructura en cuatro partes. En la primera parte se describe cómo preparar la canal de los pequeños rumiantes para su disección, la obtención de las diferentes piezas y la disección detallada de cada una de ellas. En la segunda parte se muestra cómo realizar la disección de una costilla de vacuno. En la tercera, se ofrecen los valores esperables para la composición de cada pieza, así como las fórmulas para calcular el porcentaje de cada tejido en la canal o la pieza. Por último, en la cuarta se ofrece una revisión bibliográfica a fin de que el investigador que se inicie en el tema pueda cotejar sus datos
- Development of organs and tissues in lambs raised on Spanish mountain grasslandPublication . Álvarez-Rodríguez, Javier; Sanz, Albina; Joy, Margalida; Carrasco, Salomé; Ripoll, Guillermo; Teixeira, AlfredoThe present study was conducted to establish the pattern of body development in grass-raised Churra Tensina lambs. Forty-nine single male lambs were slaughtered at three body-weight intervals, according to the commercial categories of suckling (11.191.0kg), light (22.190.8 kg) and heavy lamb (32.092.9 kg). Non-carcass and carcass components were recorded and the half left carcasses were completely dissected. Lambs showed a low growth rate of main organs in relation to empty body weight (BW) (PB0.01). Skin fleece and liver accompanied the rest of mass growth (P 0.05). The allometric coefficients of forestomachs and large intestine were higher than that of the small intestine (PB0.05). Joints related to locomotion had early development (PB0.01), whereas those belonging to the trunk grew at faster rates than did carcass weight (PB0.01). The fatty tissues had increased growth coefficients (PB0.01), whereas bone and lean coefficients decreased (PB0.01) with increasing carcass weight. Intermuscular fat attained greater growth rates in lambs slaughtered at light BW than in heavy lambs (PB0.01). However, the former group displayed lower relative growth of pelvic-renal, subcutaneous and abdominal fat than the latter (PB0.01). This trait might reflect improved investment of dietary energy towards deposition of adipose tissue through the increased digestive tract capacity. L’e´tude devait pre´ciser comment se de´veloppe le corps des agneaux Churra Tensina engraisse´s a` l’herbe. Quarante-neuf agneaux maˆ les ont e´ te´ abattus a` trois poids corporels diffe´rents selon les cate´gories commerciales d’agnelet (11,191,0kg), d’agneau le´ger (22,19 0,8 kg) et d’agneau lourd (32,092,9 kg). Les auteurs ont consigne´ les parties de la carcasse et les autres parties puis entie`rement disse´que´ le coˆ te´ gauche de la carcasse. Les principaux organes des agneaux croissent lentement comparativement au poids de la carcasse vide (PB0,01). La peau et la laine ainsi que le foie suivent le reste de l’accroissement ponde´ ral (P 0,05). Les coefficients allome´triques du secteur gastrique ante´rieur et du gros intestin sont plus e´leve´ s que ceux de l’intestin greˆ le (PB0,05). Les articulations associe´es a` la locomotion se de´veloppent haˆ tivement (PB0,01) alors que celles du tronc croissent plus vite que le poids de la carcasse (PB0,01). Les tissus adipeux se caracte´ risent par un coefficient de croissance plus e´leve´ (PB0,01), tandis que les coefficients des os et de la viande maigre diminuent (PB0,01) a` mesure que le poids de la carcasse augmente. Le taux de croissance de la graisse intermusculaire est plus e´leve´ chez les agneaux le´gers que chez les agneaux lourds (PB0,01). Cependant, les sujets du premier groupe re´ve`lent une plus faible croissance relative de la matie`re grasse pelvique-re´nale, sous-cutane´e et abdominale que ceux du second groupe (PB0,01). Cette caracte´ristique pourrait traduire une meilleure utilisation de l’e´nergie des aliments pour le de´poˆt de tissu adipeux graˆ ce a` une capacite´ supe´rieure du tube digestif.
- Estimación de la composición de la canal de ternasco por ultrasonidos en canalPublication . Ripoll, Guillermo; Álvarez-Rodríguez, Javier; Sanz, Albina; Teixeira, Alfredo; Joy, MargalidaSe sacrificaron 129 corderos tipo Ternasco de las razas Churra Tensina y Rasa Aragonesa a un peso vivo entre 22 y 24 kg. Se midieron los espesores de grasa subcutánea y el ancho y profundidad del músculo en la 10ª vértebra torácica a tres distancias de la línea media dorsal por medio de ultrasonidos en la canal caliente. Estas mismas medidas se realizaron con calibre en la canal fría y se realizó la disección en músculo, grasa total y hueso. Las medidas de ultrasonidos y de canal fría se compararon y se desarrollaron ecuaciones de predicción de la composición de la canal. El objetivo de este trabajo fue estudiar la exactitud de las medidas de ultrasonidos realizadas en canal caliente y su utilidad para estimar la composición de la canal en el rango de pesos del cordero tipo Ternasco. Las medidas de ultrasonidos en canal subestimaron los espesores medidos en canal fría. Los espesores de grasa medidos por ultrasonidos con interfase tuvieron menor diferencia que los medidos sin interfase con el espesor de la grasa de la canal fría en cualquiera de los tres puntos usados. El peso de la canal caliente explicó en mayor porcentaje la composición de la canal. Para mejorar la fiabilidad de las ecuaciones sería necesario ampliar el rango de pesos utilizados.
- Estimation of light lamb carcass composition by in vivo real-time ultrasonography at four anatomical locationsPublication . Ripoll, Guillermo; Joy, Margalida; Álvarez-Rodríguez, Javier; Sanz, B.; Teixeira, AlfredoThe objectives of this study were to study the relationship between in vivo ultrasound measurements and cold carcass measurements at 4 anatomical points of the backbone, and to establish regression equations to estimate carcass composition within the cold carcass weight range for Ternasco lambs (8 to 12.5 kg) by using ultrasonic measurements taken at a single location. Measurements of subcutaneous fat and skin thickness and of muscle depth and width were taken over the 10th to 11th and 12th to 13th thoracic vertebrae and the 1st to 2nd and 3rd to 4th lumbar vertebrae. These measurements were taken at 2 and 4 cm from the nearest end of the LM to the backbone and at 1/3 of the LM width with the probe perpendicular to and parallel to the backbone. The left sides of the carcasses were dissected into muscle, fat, and bone. Body weight (22.6 kg) and cold carcass weight (10.8 kg) were representative of Ternasco light lambs. Muscle depth measured at 2 cm, 4 cm, and 1/3 of LM width remained regular, with slight ups and downs along the spine. All the pairs of in vivo ultrasound and cold carcass measurements were significantly different (P < 0.05) and had small correlations. All the ultrasound measurements of muscle depth at any location or at any distance to the backbone were less than their equivalent cold carcass measurements, with differences ranging from 0.8 to 5.9 mm. Differences between ultrasound fat thickness + interface (US_FDGI) and cold carcass fat thickness were less than differences between ultrasound fat thickness and cold carcass fat thickness, ranging from −0.9 to −1.0 mm for the former and from −2.1 to −0.5 mm for the latter. The small differences in absolute values between US_FDGI and cold carcass fat thickness suggest that US_FDGI is the best measure of the real fatness level of the lambs. The best prediction equations for muscle, bone, and fat were developed with in vivo ultrasound data measured at the 1st to 2nd lumbar vertebrae perpendicularly to the backbone, but they had limited predictive value. To predict the muscle content of carcass, BW and muscle depth were included, and they explained 59% of variation. Fiftyone percent of total fat was predicted by BW and fat thickness, whereas only 17% of the variation in bone was predicted by 2 fat-related variables. The BW of lambs was an important predictor to improve regression equations but ultrasound measurements were the most important variables when a narrow range of BW was used.
- In vivo estimation of goat carcass composition and body fat partition by real-time ultrasonographyPublication . Teixeira, Alfredo; Joy, Margalida; Delfa, RafaelThe accuracy of ultrasound measurements to assess goat carcass composition and the partition of body fat depots was evaluated. An ultrasound machine with a 5-MHz probe and image analysis was used to assess in vivo fat thickness and muscle depth in 56 Spanish Celtiberica adult goats, in lumbar and breast body regions. The goats were slaughtered and the weight of body fat depots recorded. Measurements corresponding to the in vivo ultrasound fat thickness and muscle depth were taken on carcasses. The left sides of carcasses were completely dissected into their components. The best relationships (r = 0.94, P < 0.01) between in vivo and carcass measurements of fat thickness were obtained when measurements were taken at the sternum, and the best anatomical point was located between the third and fourth sternebrae. The best correlation coefficients (r = 0.84) for muscle depth were found for measurements taken between the third and the fourth lumbar vertebrae at 2 cm from the middle of the vertebral column. Body weight and ultrasound measurements were used to fit the best multiple regression equations to predict carcass composition and the partition of body fat depots. All equations, with the exception of those for muscle quantity, omental, and total body fat depot amounts, were computed after performing a logarithmic transformation. Body weight in association with the ultrasound measurement taken at largest LM muscle depth, between the first and second lumbar vertebrae accounted for 90% of the muscle weight. Body weight was the first variable admitted into the prediction models of muscle, mesenteric fat, and total body fat and accounted for 82, 67, and 79% of the variation in tissue weights, respectively. The ultrasound measurement of fat thickness taken at the third sternebra was the first variable admitted into the prediction models for intermuscular fat, kidney and pelvic fat, and total carcass fat and accounted for by 73, 75, 71, and 79% of the variation in the weight of these fat depots, respectively. The ultrasound measurements taken in the breast region, particularly at the third and fourth sternebrae, were the most suitable for assessing fat thickness. The results of this experiment suggest that BW associated with some in vivo ultrasonic fat measurements allow the accurate prediction of goat carcass composition and body fat depots.
- In vivo ultasonic measurements and live weight for predicting carcass quality in Churra Tensina mountain breed lambsPublication . Delfa, Rafael; Joy, Margalida; Sanz, Albina; Panea, Begoña; Álvarez-Rodríguez, Javier; Alberti, P.; Teixeira, AlfredoForty-six single male lambs ofChurra Tensina mountain breed with a live-weight ranging from 19.9 . to 24.4 kg ('Temasco' carcass commercial type) were scanned by ultrasound (ALOKAmodel SSD- 900, with a 7.5 MHz probe) to determine M. longissimus dorsi depth and subcutaneous fat thickness between the lOth-lith, 12th-13th dorsal vertebrae and 1st-2nd, 3rd-4th lumbar vertebrae. Lambs were slaughtered and carcasses were cooled at 4 °C for 24 h and halved. The left side was divided according to a standardised jointing procedure, based on six anatomical regions: shoulder, long leg, anterior ribs, ribs, flank and neck. Each joint was then disseCted into ,muscle, bone plus remainder and subcutaneous, inter-muscular, kidney and pelvic fat. Thein vivo ultrasound measureme~ts plus slaughter weight were fitted to predict carcass tissue composition by Stepwise regression analysis. All the developed models were highly significant (P
- In vivo ultrasonic measurements and live weight for predicting carcass quality in Churra Tensina mountain breed lambsPublication . Delfa, Rafael; Joy, Margalida; Sanz, Albina; Panea, Begoña; Teixeira, AlfredoForty six single male lambs of Churra Tensina mountain breed with a live weight ranging from 19.9 to 24.4 Kg producers of carcass type Temasco, were scanned by ultrasound (ALOKA model SSD-900, with a 7.5 MHz sounder) to determine M. Longissimus dorsi depth and subcutaneous fat thickness between the I Olh_l ]lh, 12th_13th dorsal vertebra and PI_2nd, 3rd_4lh lumbar vertebra. Lambs were slaughtered after 24 h. fasting. Carcasses were cooled at 4' C for 24 h. and halved. The left side was divided according to a standardised jointing procedure, based on six anatom ically regions: shoulder. long leg, anterior ribs, ribs, flank and neck. Each joint was then dissected into muscle, bone plus remainder and subcutaneous, inter-muscular, kidney and pelvic fat. The in vivo ultrasound measurements plus slaughter weight were fitted to predict carcass tissue composition by Stepwise regression analysis. All the developed models were highly significant (P
- Subjective measurements of fat cover and kidney knob and channel fat for predicting leg and rib tissue composition of Blanca Celtibérica kids.Publication . Delfa, Rafael; Panea, Begoña; Joy, Margalida; Jiménez Badillo, M.R.; Teixeira, AlfredoCCW, the assess of FC on two scores (1-5) and (1-15) and the assess of KKCF amount on two scores (1-3) and (1-9) were used as predictors of leg and rib tissue composition of 31 Blanca Celtibérica kids, with an average CCW of 6,9± 2,1 Kg. Proportionately 97% of the variation in muscle weight was accounted for by variation in CCW and the inclusion of KKCF amount scored from 1 to 9 improve the precision of the prediction 1%, reducing the RSD in 11,8%. The inclusion of KKCF amount (scored 1-3) did not improve the precision of the rib muscle composition but reduced the RSD in 6,2%. In relation to bone composition of both joints, 95% and 73% of the variation of the leg and rib bone weight, respectively were accounted for by variation on CCW. The 87 and 85% of the leg and rib fat weight variation were accounted for by variation in CCW associated with fat score (1-15) and KKCF amount (1-3) with a RSD of 17 and 32,4 g, respectively. El peso canal fría, grado de engrasamiento con dos escalas de (1-5) y de (1-15) puntos y cantidad de grasa pélvico renal con dos escalas de puntuación (1-3) y (1-9) fueron utilizados como predictores de la composición tisular de la pierna y costillar de 31 cabritos de raza Blanca Celtibérica, con una media de peso canal fría de 6,9± 2,1 Kg. La variación del peso canal fría explicó el 97% de la variación en el peso del músculo de ambas piezas y la entrada en el modelo de la cantidad de grasa pélvico renal (1-9) incrementó un 1% la precisión de la estimación del peso del músculo del costillar con una reducción asociada del RSD de un 11,8%. A su vez la entrada en la ecuación de predicción del peso del músculo del costillar, de la cantidad de grasa pélvico renal (1-3) no mejoró la precisión de la estimación, pero sí que supuso un 6,2% de reducción del RSD. Respecto a la predicción del peso del hueso en ambas piezas, el 95% de la variación en el peso del mismo en la pierna, fue explicado por la variación en el peso de la canal fría, mientras que la variación en el peso de esta misma variable tan solo explicó el 73% de la variación en el peso del hueso del costillar. Finalmente, la variación del peso canal fría, engrasamiento (1-15) y cantidad de grasa pélvico renal (1-3) explicó el 87 y 85% de la variación en el peso de la grasa total de la pierna y costillar con unas RSD asociadas de 17,0 y 32,4 g, respectivamente.
- Subjective measurements of fat cover and kidney knob and channel fat for predicting shoulder, neck and flank plus breast tissue composition of Blanca Celtibérica kids.Publication . Delfa, Rafael; Joy, Margalida; Panea, Begoña; Jiménez Badillo, M.R.; Teixeira, AlfredoCCW, the assess of FC on two scores (1-5) and (1-15) and the assess of KKCF amount on two scores (1-3) and (1-9) were used as predictors of shoulder, neck and flank plus breast tissue composition of 31 Blanca Celtibérica kids, with an average CCW of 6,9± 2,1 Kg. Proportionately 97, 91 and 92% of the variation in muscle weight of shoulder, neck and flank plus breast, respectively were accounted for by variation in CCW. The variation in CCW also explained 96, 49 and 86% of the variation of shoulder, neck and flank plus breast bone tissue composition. The inclusion in the prediction equation for neck bone weight of FC (1-15), increase the precision in 7% and reduced the RSD in 5,7%. Finally the variation in CCW and FC (1-15) explained 87, 76 and 90% of the variation in fat weight of shoulder, neck and flank plus breast, respectively. Nevertheless the inclusion of KKCF amount (1-3) in the prediction equations of fat weight of shoulder and flank plus breast increase the precision in 2% and reduced the RSD in 6,1 and 10,2%, respectively. El peso canal fría, grado de engrasamiento con dos escalas de (1-5) y de (1-15) puntos y cantidad de grasa pélvico renal con dos escalas de puntuación (1-3) y (1-9) fueron utilizados como predictores de la composición tisular de la espalda, cuello y bajos de 31 cabritos de raza Blanca Celtibérica, con una media de peso canal fría de 6,9± 2,1 Kg. La variación del peso canal fría explicó el 97, 91 y 92% de la variación en el peso del músculo de la espalda, cuello y bajos respectivamente. Así mismo, la variación del peso canal fría explicó el 96, 49 y 86% de la variación en el peso del hueso de las mismas piezas y en el mismo orden. No obstante la entrada en la ecuación de predicción del peso del hueso del cuello, del engrasamiento (1-15) mejoró la precisión de la estimación en 7 puntos porcentuales, con una reducción del RSD asociado del 5,7%. Finalmente la variación del peso canal fría y engrasamiento (1-15) explicó el 87, 76 y 90% de la variación en el peso de la grasa total de la espalda, cuello y bajos. No obstante la entrada en la ecuación de predicción de la cantidad de grasa pélvico renal (1-3), mejoró la precisión de la estimación de la variación del peso de la grasa total de la espalda y bajos en un 2%, con una reducción del RSD asociado de un 6,1 y 10,2% respectivamente.