Carcass Ultrasound

Carcass Assessment for Genetic Improvement Programs

Selection within breeds is an important tool used in the genetic improvement of beef cattle, and the speed of genetic change depends on the heritability of the trait, the intensity of selection, and the generation interval. Carcass characteristics present estimates of medium to high heritability, which justifies the selection of genetically superior animals for these characteristics.

Aval Serviços Tecnológicas works in partnership with genetic improvement programs and breed associations, capturing accurate measurements of characteristics evaluated by ultrasound, in live animals. The characteristics currently used by genetic improvement programs are rib eye area (AOL) and subcutaneous fat (EG), measured between the 12th and 13th ribs, in the Longissimus dorsi muscle; subcutaneous fat over the Biceps femoris muscle (EGP8); and intramuscular fat or marbling, which should only be evaluated in animals whose group has an average of at least 5 mm of subcutaneous fat thickness. The deposition of intramuscular fat occurs after the deposition of subcutaneous fat, so only animals with 5 mm of fat or more will have good quality images for the genetic evaluation of this characteristic.

The Rib Eye Area represents greater muscularity, therefore greater carcass yield, guaranteeing the producer a better economic return when slaughtering their animals.

The fat thickness measurement is an efficient indicator of carcass finish. Subcutaneous fat is of great importance in the industrialization of meat, as it plays the role of thermal insulator during the carcass cooling process, which must be done slowly and gradually so as not to cause shortening of the muscle fibers, and consequently, hardening of the meat. . For this coverage to be efficient, it is important to have a homogeneous distribution over the carcass.

Selection for this characteristic also brings benefits to the reproductive rates of your herd, due to its correlation with body score, bringing better performance in sexual precocity programs and in breeding seasons with an increase in the reconception rate.

The Reviews

To use these measurements in genetic evaluations of zebu breeds, research was initially necessary to ensure the reliability and accuracy of the data collected and the improvement of methodologies for collecting, analyzing and interpreting images. Furthermore, the development patterns, the quantitative relationships between ultrasound measurements and those from the refrigerator, the heritabilities and covariances of these measurements and the ideal ages for evaluation were determined in studies developed by AVAL and ANCP.

These assessments are carried out by rigorously trained and accredited technicians ( www.ultrasoundbeef.com ). Field technicians, as well as laboratory technicians, are only accredited after demonstrating their skills, which are statistically evaluated by accuracy, repeatability, technical deviation and correlation.
AVAL's commitment to breed associations and breeders is to provide high quality data for the generation of DEPs. For this purpose, accreditation follows a protocol where all technicians will be working within the same internationally standardized methodology.


This process is done in two steps:

 

1) field work, where images are collected in the field, stored by the image capture system and subsequently sent to the laboratory of the Ultrasonography Technology Reference Center, and

2) laboratory analysis, images are interpreted in the laboratory and rigorously monitored to ensure data quality.

Ultrasound Age By Race

It is known that ultrasound has been used to evaluate beef carcasses, however its applicability and efficiency depends on several criteria adopted. Among these criteria are technical training, image collection, image interpretation, data processing.

In addition to these, other requirements are also necessary to obtain good results. Research works already present specific evaluation parameters for each breed, since they have different physiological and genetic characteristics.


Below we present some of the main criteria necessary for a good assessment of your animals.

Age adopted for image collection (days)

Raça

Machos (M)1

Fêmeas (F)1

Machos (M) confinados

Fêmeas (F) confinados

Nelore

490 – 610

490 – 610

330 – 400

330 – 400

Brahman

490 – 610

490 – 610

330 – 400

330 – 400

Guzerá

490 – 610

490 – 610

330 – 400

330 – 400

Tabapuã

490 – 610

490 – 610

330 – 400

330 – 400

Angus

-

-

320 – 340

320 – 360

Canadian Angus

-

-

320 – 440

320 – 460

Brangus

-

-

310 – 430

310 – 430

Charolais

-

-

320 – 430

320 – 430

Chianina

-

-

320 – 440

320 – 460

Gelbvieh

-

-

320 – 410

320 – 410

Hereford

-

-

330 – 430

330 – 430

Limousin

-

-

300 – 450

300 – 450

Red Angus

-

-

320 – 440

320 – 460

Salers

-

-

330 – 450

330 – 450

Simental

-

-

330 – 440

330 – 440

BIF Guidelines

-

-

320 - 410

320 - 410

1 – These standardized ages are for animals in the field, which have good body condition, that is, a good nutritional plan so that the animals can present their potential and variability among the characteristics evaluated. Therefore, these animals must be evaluated in this age range with a minimum weight of 300 kg.


* – Research projects are underway to establish evaluation parameters for these breeds. Breeders interested in these research projects should contact the breed association, ANCP or even AVAL .


We would like to inform breeders interested in the assessment of intramuscular fat, i.e. marbling; that the group of animals must present on average a minimum of 5 mm of subcutaneous fat. The deposition of intramuscular fat occurs after the deposition of subcutaneous fat, so only animals with 5 mm of fat or more will have good quality images for the genetic evaluation of marbling.

From the point of view of genetic evaluation, it is important to evaluate the entire group, and not just animals that have fat thickness above 5 mm. Therefore, it is recommended that batch marbling data only be collected, interpreted and sent when the batch average presents appropriate conditions for marbling analysis.

Bovine carcass anatomy

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Measurements on beef carcass

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Assessment Methodology

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Ultrasound in the future

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Tips for Creators

In order to help clarify some doubts and also improve the development of field services during the animal carcass evaluation period, below is a list of important points to be observed and evaluated before the evaluations begin.

Responsabilidade do Criador

Por que é Importante?

Agendamento prévio

Técnicos de campo usam os seus próprios métodos para agendamento, por isso quanto mais cedo você entrar em contato para agendar as avaliações de ultrassom é mais provável de se conseguir a data desejada para o serviço. Isso também pode lhe dar a oportunidade desta data ser agendada com os outros criadores na mesma região e dividir os custos de viagem. Antes de agendar ter uma idéia do número de cabeças para que o técnico possa estimar o tempo necessário para completar a sessão de escaneamento dos animais. Escolha uma data de avaliação que fique dentro da janela de idade adequada para a raça, para que os dados não sejam perdidos.

Planilhas de campo

A planilha de campo com informações como RGN, idade, sexo, manejo, lote de manejo, é necessária para verificar se todos os animais que estão na idade adequada foram avaliados e acrescentar informações de animais adicionais o que evitará o atraso no laboratório de interpretação.

Tronco de contenção

Os animais devem sempre ser contidos em um tronco de contenção adequado para que se possa fazer a avaliação. Isso reduz o movimento e melhora o contato, promovendo imagens com maior qualidade. Ele também acelera as coisas!

Fornecer Eletrecidade Limpa

A eletricidade é necessária para alimentar o equipamento de ultrassom, computador, tosquiadeira (quando necessário), etc. Um circuito sobrecarregado ou sem aterramento poderá causar interferência e pode comprometer o processamento das imagens de gordura intramuscular. Se estiver usando um uma tosquiadeira pode ser necessário fornecer duas fontes de alimentação. Um gerador pode ser usado se necessário.

Tosquia para ultrassom

É necessário que os animais que serão avaliados tenham o pêlo com menos de 1,3 cm de comprimento, para uma melhor qualidade da imagem. Animais zebuínos não necessitam deste procedimento.

Manter os animais  secos

Óleo vegetal é o agente de acoplamento usado para permitir que as ondas de ultrassom penetrem a pele e se tenha a formação das imagens. Água e óleo não se misturam. Quando o animal está molhado tem-se uma redução do contato e uma imagem de baixa qualidade. Sob uma cobertura os animais molhados demoram em torno de 40 a 60 minutos para secarem.

Pesar os animais

Os animais devem ser pesados no dia da avaliação de carcaça, entretanto, podem ser pesados até sete dias antes ou depois da avaliação.

Saiba que pesagens após a data da avaliação irá atrasar o envio de imagens para o laboratório. 

Manter os animais entrando no tronco

Basicamente, por favor, não conte com o técnico para “tocar” os animais, a função do técnico é fazer a avaliação de ultrassonografia e as anotações cabíveis, outras funções podem atrapalhar o rendimento do serviço, no entanto, muitos técnicos gostam disso e estão dispostos a ajudar!