Browsing by Author "Delfa, Rafael"
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- Body weight and ultrasons as predictors of carcass quality and fat partition in adult goatsPublication . Delfa, Rafael; Teixeira, Alfredo; González, C.The main objectives of the present work were to establish the comparison between nine measurements of lumbar fat thickness. nine of the M. Longissimus dorsi depth and four of the breastbone fat thickness. Ali these controls were made by ultrasounds in alive animals. The same measurements were taken in the carcasses. The aim was also determining the accuracy in the application of the measurements taken by ultrasounds as predictors of the carcass composition and of the fat depots in the body of 40 dry. empty adul Blanca Celtibérica goats with a scoring range of the breastbone body condition from !.5 to 4.5. The best results concerning the first objective were obtained by taking the corresponding measurements between the 3rd and the 4th lumbar vertebrate, in the left side of the carcass. It was also evident that the C measurement reaches higher correlation coefficients when it is generally measured at 4 cm and at 1/3 and 2 cm in the case of the B measurement. However, the highest correlations were obtained between the breastbone fat thickness measured by ultrasounds and the same measurements taken in the carcass. Concerning the second objective. 90% of the weight variation in the muscle was explained by the variation of the slaughterhouse live weight and of the B measurement taken between the 1st and the 2nd lumbar vertebrae. In relation to fat depots, the slaughterhouse live weight was the first variable in the equations for the prediction of the total fat depots in the carcass and in the animal body. explaining 82% of the variation of these depots. The inclusion in the equations of measurement C taken between the 1st and the 2nd lumbar vertebrae and that taken in the 2nd sternebra increased the precision of the estimations in 10% for the carcass total fat and in 12% for the animal body total fat, but in this last case, the measurement taken in the 2nd sternebra entered into the equation before measurement C. Los principales objetivos del presente trabajo fueron establecer la comparación entre 9 medidas de espesor de grasa lumbar, 9 de profundidad del M. Longissimus dorsi y 4 del espesor de grasa esternal. rodas ellas realizadas con ultrasonidos en animal vivo, con las mismas medidas tomadas en la canal. A si como determinar la precisión en la utilización de las medidas realizadas con ultrasonidos como predictoras de la composición de la canal y de los depósitos adiposos del cuerpo de 40 cabras adultas. vacías y secas. de raza Blanca Celtibérica con un rango de puntuación de la condición corporal esternal de 1.5 a 4.5. Los mejores resultados respecto al primer objetivo se obtuvieron efectuando las correspondientes mediciones entre la 3' y 4' vértebra lumbar, en cl lado izquierdo de la canal. Siendo evidente así mismo que la medida C alcanza unos coeficientes de correlación superiores cuando se mide a 4 cm generalmente y a 1/3 y 2 cm cuando se trata de la medida B. Sin embargo. las correlaciones más altas se obtuvieron entre el espesor d e la grasa esternal medido con ultrasonidos y las mismas medidas tornadas en la canal. Respecto al segundo objetivo, el 90% de la variación del peso del músculo fue explicado por la variación del peso vivo matadero y de la medida B tomada entre la 1ª y 2ª vértebra lumbar. En lo referente a los depósitos adiposos, el peso vivo matadero fue la primera variable en las ecuaciones de predicción de los depósitos adiposos totales de la canal y del cuerpo del animal, explicando el 82% de la variación de estos depósitos. La inclusión en las ecuaciones de la medida C tomada entre la 1ª y 2ª vértebra lumbar y la realizada en la 2• esternebra incrementó la precisión de las estimaciones en un 10% para la grasa total de la canal y en un 12% para la grasa total del cuerpo del animal, pero entrando en la ecuación en este último caso en orden inverso al anterior.
- Calidad de la canal ovinaPublication . Delfa, Rafael; Teixeira, AlfredoLa canal ovina en España fue definida par Orden del 18 de Septiembre de 1975, como el cuerpo del animal sacrificado, sangrado, desollado, eviscerado, Separada de la cabeza a nivel de la articulaci6n occípito-atloidea y sin extremidades, que se cortarán a nivel de las articulaciones carpo-metacarpiana y tarsometatarsiana. Conservara la cola, los pilares, la porción periférica carnosa del diafragma, los testículos, los riñones y la grasa ele riñonada y de la cavidad pélvica; las mamas se separarán en las hembras adultas.
- Carcass and meat quality in light lambs from different classes in the European grading systemPublication . Sañudo, Carlos; Alfonso, Matilde J.; Sánchez, Ana Cristina; Delfa, Rafael; Teixeira, AlfredoFat, quantity and quality, are important aspects for consumers (Sendim et al., 1997), who are more and more interested in healthy products and usually prefer lean meat and carcasses, although fat is positively associated with acceptability. Thus, Jeremiah (1998) found that the percentage of unacceptable cuts was higher in lean than fat categories, similar findings being obtained by Paul et al., ( 1964) and Smith et al., (1970). For this reason practically all carcass classification systems around the world include fatness score as a criterion of quality and price (EEC n° 2 137/92 and 46 1/93 regulations; Moxhan and Brownlie (1976)). Other characteristics such as age, sex, weight, carcass length, meat colour and specially conformation score are also used, but they have a lower market significance and a lower price influence. Inside the EU there are two different schemes for lamb classification: one for carcasses up 13 kg and other for light carcasses under 13 kg. In the latter scheme, since Mediterranean carcasses were systematically penalised because of their natural poor morphology (walker breeds), low subcutaneous/internal fat ratio and light weights, conformation score is not considered. Only weight (three categories: < 7.0 kg, 7.1-10.0 kg and 10.1-13.0 kg), meat colour and fat class are included Several studies have shown weak relationships between lamb quality grades and palatability assessments in heavy or medium weight carcasses (Jeremiah et al., 1972; Crouse and Ferrel, I 982), but there has been no investigation of this relationship in light lambs. On the other hand, it seems essential to know if any classification is, or is not, related with real carcass value and quality.
- Carcass and meat quality in light lambs from different fat classes in the EU carcass classification systemPublication . Sañudo, Carlos; Alfonso, Matilde J.; Sánchez, Ana Cristina; Delfa, Rafael; Teixeira, AlfredoNinety commercial lamb carcasses were analysed according to the four different fat classes in the light lamb European classiffication system. Shoulder fat increased 3%, muscle decreased 2% and bone decreased 1% for each class increase. No signifficant differences were found among fat classes regarding pH, WHC, cooking losses, juiciness, myoglobin content, meat colour measured immediately after cutting (L*, a*, b*), odour intensity or flavour quality. Some differences were found in colour evolution through ageing. Shear force decreased and tenderness and flavour intensity increased with fat class but this effect was only signifficant in the leanest animals.
- Carcass composition and body fat depots of Galego Bragançano and crossbred lambs by Suffolk and Merino Precoce sire breedsPublication . Teixeira, Alfredo; Delfa, Rafael; Treacher, T.The main purpose of this work was to compare two breeds of improved rams (Suffolk and Merino Precoce) with the local Galego Bragancano breed for the prodtuction of crossbred slaughter lambs and to evaluate which cross was move adapted for meat production from the local breed in locations in the north-east of Portugal. The experiment was carried out over a 4-year period in three locations: (1) a farm with an intensive management; (2) an upland farm (400 to 600 m); and (3) a hill farm (above 800 m). Within each flock with 90 Galego Bragancano ewes, two rams of each of the sire breeds were used: Galego Bragancano, Suffolk and Merino Precoce. The lambs were slaughtered at 20 and 40 kg, to obtain the carcass weight range of 8 to 14 kg. The left sides of 151 carcasses were dissected into muscle, subcutaneous fat, intermuscular fat and bone. The lambs from location 1 had the highest carcass muscle proportion and the lowest carcass intermuscular fat proportion; their differences over locations 2 and 3 were 13 and 16 g/kg for muscle proportion and 11 and 19 g/kg for intermuscular fat proportion, respectively. The differences between breeds were relatively small and not significant. However the Suffolk crosses had less kidney, knob and channel fat than the other genotypes (5 and 12 g/kg less than Merino crosses and Bragancano, respectively). The Suffolk crosses tended to have less body fat.
- Carcass conformation and joints composition of Churra Galega Bragançana and crossbred lambs by Suffolk and Merino Precoce sire breedsPublication . Teixeira, Alfredo; Cadavez, Vasco; Delfa, Rafael; Bueno, M.S.Carcasses of Churro Galego Bragançano purebred and Suffolk and Merino Precoce crossbred lambs reared under three different conventional production system of northeast of Portugal were evaluated. Carcasses of male lambs had larger muscle longissimus width (P < 0.05) and smaller subcutaneous fat thickness (P < 0.05) than the female lambs. Carcasses of crossbred lambs had higher (P < 0.05) compactness indices and leg and shoulder proportion than Bragançano purebred. Suffolk crossed had lower KKCF proportion (P < 0.05) than Bragançano and Merino crossbred lambs. Male lambs had higher (P < 0.05) muscle proportion in almost all carcass joints than the female lambs. It was concluded that Suffolk can be used as sire breed in Bragançano ewes to produce lambs with leaner and more compact carcasses and better fat distribution, which allows slaughtering at higher slaughter weight, specially in more intensive production systems. Female lambs should be slaughtered at lower carcass weight than male lambs in order to produce carcasses with the same fattening degree.
- Cold carcass weight, fat thickness, C measurement and longissimus dorsi depth for predicting the carcass composition of Rasa Aragonesa ewes with different body condition scorePublication . Delfa, Rafael; Teixeira, Alfredo; Colomer-Rocher, F.The precision of the use of cold carcass weight, fat thickness, C measurement and longissimus dorsi depth for predicting the carcass composition were determined in 52 adult Rasa Aragonesa ewes aged 10 (s.d. 2) years and ranging in body condition score (BCS) front 1.5 to 4.5. The cold carcass weight is the best predictor of intermuscular fat (1'=0.94) and the inclusion of the C measurement in multiple regression with the cold carcass weight estimates with accuracy the subcutaneous fat (r2=0.91). The pelvic and kidney fat can be predicted with the same precision by cold carcass weight in multiple regression with fat thickness or BCS (r2=0.86). 95% of the variation in total carcass fat was accounted for by variation in cold carcass weight and fat thickness. The best muscle carcass predictors were cold carcass weight in multiple regression with fat thickness or C measurement (r2=0.91).
- Composicion regional y tisular de la canal caprinaPublication . Delfa, Rafael; Teixeira, Alfredo; Colomer-Rocher, F.El estudio de la composición regional o anatómica se realiza mediante la utilización del despiece que, según la legislación, es la acción de separar determinadas partes anatómicas de la canal en base a divisiones establecidas por intereses comerciales. Existen diferentes definiciones según autores, así para Sañudo y Sierra (1986), es el arte complejo que trata de adecuar unos máximos beneficios a unos gustos del mercado, dividiendo la canal en diferentes trozos a los que se les adscribe distintas categorías.
- Conformación, engrasamiento y sistemas de clasificación de la canal caprinaPublication . Delfa, Rafael; Teixeira, Alfredo; Colomer-Rocher, F.España es el segundo país productor de ganado caprino de In UE, con un 21 % del censo total, tras Grecia que posee el 48,7% (Delfa, 2004). A pesar de ello no existe en nuestro país ningún distintivo o Marca de Calidad para la canal y carne caprina, mientras que en Portugal, con un censo del 27,8% del español y una producción de carne que tan solo supone el 13,9% de la española, tiene cinco Indicaciones Geográficas Protegidas. Existe por lo tanto un gran desconocimiento sobre las razas caprinas autóctonas españolas, que se acrecienta con las de aptitud cárnica. A este respecto, Devendra (2000) y Lebbie (2000) indicaban la existencia de importantes lagunas en el conocimiento de esta especie, reconociendo recientementc Morand-Fehr y Lebbie (2004) la necesidad de analizar su situación actual con el fin de prepararla para los retos de un próximo futuro.
- Conformation and joint carcass composition of Galego Bragançano crossbred lambs by Suffolk and Merino Precoce sire breedsPublication . Teixeira, Alfredo; Cadavez, Vasco; Delfa, Rafael; Treacher, T.