Recursos de colección

Biblioteca Digital do IPB (53.442 recursos)

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Mostrando recursos 1 - 12 de 12

  1. Influence of production factors on the characteristics of meat from ruminants in Mediterranean area

    Teixeira, A.; Delfa, R.; Alberti, P.
    The production systems or cattle sheep and goats in Mediterranean area and the factors linked with carcass and meat quality are discussed. The production systems in the mountain and semi-arid areas, typical of Mediterranean, are refereed. Finally a group or actions to be taken regarding the improvement of meat production from ruminants is suggested.

  2. Application of the regulations 2081 and 2082/92 in Portugal, their importance in the organization and valuation of the portuguese traditional products

    Sousa, Fernando Ruivo de
    In Portugal like in other Mediterranean Countries there is a group of food products which constitutes a main cultural heritage of this country due to their tradition, age, quality and importance concerning [0 consumption habits. For that reason it is important not only to keep that heritage hut al so transmit it to future generations and take advantage or the huge possibilities or some products to allow the developing or underprivileged regions where most or they come from.

  3. Progestagen treatment associated with different doses of eCG to advance the breeding season in Churra Galega Bragançana ewes

    Valentim, Ramiro; Azevedo, Jorge; Mendonça, Álvaro; Fontes, Paulo; Galvão, Lurdes; Cardoso, Manuel; Velasco, Helena; Maurício, Raimundo; Correia, Teresa Montenegro
    In order to assess the effects of a long-term progestagen treatment associated with different doses of eCG (equine Chorionic Gonadotropin) to advance the breeding season in Portuguese Churra Galega Bragançana ewes, an initial group of 41 females (2 were later rejected) aged between 2 and 7 years was used. In middle May, all ewes were treated with an intravaginal sponge impregnated with 20 mg of fluorogestone acetate (FGA) for 12 days. Half ewes received an injection (i.m.) of 500 UI of eCG and the other half an injection (i.m.) of 750 UI of eCG at sponge removal time. Blood samples...

  4. Effects of PGF(2A) administration at the onset or the end of a short-term progestagen treatment in Serrana goats

    Correia, Teresa Montenegro; Azevedo, Jorge; Mendonça, Álvaro; Fontes, Paulo; Galvão, Lurdes; Cardoso, Manuel; Velasco, Helena; Maurício, Raimundo; Valentim, Ramiro
    In order to assess the reproductive effects of Prostaglandin F2alfa (PGF2alfa) administration at the onset or the end of a progestagen treatment in Portuguese Serrana goats, an initial group of 44 females (5 were later rejected for several reasons) aged between 3 and 7 years was used. In May (beginning of the breeding season), all goats were treated with an intravaginal sponge impregnated with 20 mg of fluorogestone acetate (FGA) for 5 days and injected (i.m.) with 300 UI of eCG at sponge removal time. Half goats received an injection (i.m.) of 100 ug of cloprostenol at sponge insertion time...

  5. An implantable microsystem for electrical resistance and temperature measurements in cows with wireless capabilities suitable for reproductive management

    Morais, R.; Valente, A.; Almeida, José Carlos; Silva, Amélia M.; Soares, Salviano; Valentim, Ramiro; Azevedo, Jorge
    In the cattle breeding industry, where artificial insemination techniques are employed, the successful detection of oestrus onset leads to considerable cost saving in herd management. One of the most reliable approaches is based on the determination of progesterone concentration in milk. However, these methods rely on the biosensor concept where a biological substrate is used in a chemical binding reaction to, directly or indirectly; produce some effect (electrical or light) that is used at the transducer level. These methods present several drawbacks concerning real-time measurements due to the complexity of the reactions involved and reagent/waste handling. Another approach is to...

  6. "Mirandesa" cattle breed: farm structure, management and marketing

    Fragata, António; Sousa, Fernando Ruivo de
    In spite pof losses suffered in the last decades, the "Mirandesa" cattle breed still plays an important economic and social role and the carcass is famous for the quality of the "posta mirandesa", a very appreciated dish by the rich gastronomy of Portugal. The area studied is the highlands of Northeast of Portugal (Trás-os-Montes) which range from 700 to 1000 metres. The farming systems adopted by farmers are very low intensity animal production systems and the meat of the "Mirandesa" cattle breed has benn marketed as PDO since 1996, within the meaning of the EU rules adopted under the reform...

  7. Mirandes cattle breed: genetic base and breed improvement

    Sousa, Fernando Ruivo de; Fragata, António
    The "mirandês cattle breed has had a herd book since 1913 and the agricultural service has implemented a programme of genetic improvemment since the 70's. However, in spite of what has been expected, positive results weren't found on that programme and the "mirandês" cattle breed has gone into a decline. This paper analyses the strategies of several cattle breeder types and the genetic demographic structure of cattle within a community in northeast of Portugal.The present organization of the breed improvement, centered on cattle breeders of pure breed and on farms whith a great number of cows, does not permit genetic...

  8. Subcutaneous fat depth magnitude influences its measurement errors: a simulation study

    Cadavez, Vasco; Rufino, José; Fonseca, António
    The objectives of this study were to evaluate the impact of proportional and absolute errors on subcutaneous fat depth (SFD) measurements, and the effects on the stability of models to predict the lean meat proportion (LMP) of lamb carcasses. Ninety eight lambs (72 males and 26 females) of Churra Galega Bragançana breed were slaughtered, and carcasses were weighed (HCW) approximately 30 min after exsanguination. During carcasses quartering a caliper was used to perform SFD measurements, over the maximum depth of longissimus muscle (LM), between the 12th and 13th ribs (C12), and between the 3rd and 4th lumbar vertebrae (C3). A...

  9. Incorporation of Boletus edulis extract in beef burgers patties: preliminary evaluation of the antioxidant protective effects

    Grangeia, Cátia; Batista, Cátia Emanuela Oliveira; Raposo, Manuel; Barros, Lillian; Cadavez, Vasco; Ferreira, Isabel C.F.R.
    The objective of this study was to analyse the antioxidant protective effects of the incorporation of Boletus edulis extract in beef burgers. The relationship of total lipids/fatty acids to lipid peroxidation of hamburger during storage was examined. Beef burgers samples (lipids content: 15–18%) were stored for 8 days, and thiobarbituric acid reactive substances (TBARS) formation inhibition, free radical scavenging activity and reducing power were determined. The antioxidant potential increased with the amount of extract added to beef burgers, giving higher radical scavenging properties and TBARS inhibition capacity. These findings indicated that Boletus edulis extract had a protective antioxidant effect against...

  10. Using multiple regression, neural networks and supprot vector machines to predict lamb carcasses composition

    Silva, Filipe; Cortez, Paulo; Cadavez, Vasco
    The objective of this work was to use a Data Mining (DM) approach to predict, using as predictors the carcass measurements taken at slaughter line, the composition of lamb carcasses. One hundred and twenty ve lambs of Churra Galega Bragan cana breed were slaughtered. During carcasses quartering, a caliper was used to perform subcutaneous fat measurements, over the maximum depth of longissimus muscle (LM), between the 12th and 13th ribs (C12), and between the 1st and 2nd lumbar vertebrae (C1). The Muscle (MP), Bone (BP), Subcutaneous Fat (SFP), Inter-Muscular Fat (IFP), and Kidney Knob and Channel Fat (KKCF) proportions of lamb carcasses were computed. We used the rminer R library and compared three...

  11. Flow of physiological fluids in microchannels: the sedimentation effect

    Garcia, Valdemar; Correia, Teresa Montenegro; Dias, Ricardo P.; Lima, R.
    Microfluidic devices are becoming one of the most promising new tools for diagnostic applications and treatment of several chronic diseases. Hence, it is increasingly important to investigate the rheological behaviour of physiological fluids in microchannels. The main purpose of the present experimental work is to investigate the flow of two different physiological fluids frequently used in microfluidic devices. The working fluids were physiological saline (PS) and dextran 40 (Dx40) containing about 6% of sheep red blood cells (RBCs), respectively. The capillaries were placed horizontally on a slide glass and the flow rate of the working fluids was kept constant by using a syringe pump. By means of a camera the images were...

  12. Lamb meat tenderness prediction using neural networks and sensitivity analysis

    Cortez, Paulo; Portelinha, Manuel; Rodrigues, Sandra; Cadavez, Vasco; Teixeira, A.
    The assessment of quality is a key factor for the meat industry, where the aim is to fulfill the consumer’s needs. In particular, tenderness is considered the most important characteristic affecting consumer perception of taste. In this paper, a Neural Network Ensemble, with feature selection based on a Sensitivity Analysis procedure, is proposed to predict lamb meat tenderness. This difficult real-world problem is defined in terms of two regression tasks, by using instrumental measurements and a sensory panel. In both cases, the proposed solution outperformed other neural approaches and the Multiple Regression method.

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