38 research outputs found
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Early pair housing increases solid feed intake and weight gains in dairy calves
Dairy calves have traditionally been kept in individual pens throughout the milk-feeding period. Social rearing is associated with increased solid feed intake and hence higher weight gains before and after weaning. Little is known about the effect of the age at which social housing begins. The aim of this study was to assess the effects of early versus late pairing on feeding behavior and weight gain before and after weaning. Holstein bull calves were reared individually (n=8 calves), or paired with another calf at 6 ± 3 d (n=8 pairs) or 43 ± 3 d of age (n=8 pairs). All calves were fed 8 L of milk/d for 4 wk, 6 L/d from 4 to 7 wk and then milk was reduced by 20%/d until calves were completely weaned at 8 wk of age. Calves were provided ad libitum access to calf starter and a total mixed ration (TMR). Body weight and feed intake were measured weekly from 3 to 10 wk of age. Intake of calf starter was significantly higher for the early-paired calves than for individually-reared and late-paired calves throughout the experimental period. At 10 wk of age, starter dry matter intake (DMI) averaged 2.20 ± 0.22 kg/d, 1.09 ± 0.25 kg/d and 1.26 ± 0.33 kg/d for early pair, late pair and individually housed calves, respectively. Intake of TMR did not differ among treatments, TMR dry matter intake (averaged 3.27 ± 0.72 kg/d, 3.08 ± 0.46 kg/d, and 2.89 ± 0.54 kg/d for the same three treatments). Calves in the early pair treatment also showed significantly higher average daily gain (ADG) over the experimental period (0.89 ± 0.04 kg/d versus 0.76 ± 0.04 kg/d and 0.73 ± 0.04 kg/d for the early paired, individual and late-paired calves, respectively). These results indicate that social housing soon after birth can increase weight gains and intake of solid feed
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time, and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space. While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes, vast areas of the tropics remain understudied. In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity, but it remains among the least known forests in America and is often underrepresented in biodiversity databases. To worsen this situation, human-induced modifications may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge, it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%â18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
Forma e função em vacas Braford: o exterior como indicativo de desempenho e temperamento
O objetivo deste trabalho foi buscar ferramentas que possam auxiliar os produtores na tomada de decisĂŁo ao selecionar vacas mais adaptadas Ă s condiçÔes ambientais e que apresentem temperamento mais dĂłcil. Para isso, foram tomadas 11 medidas corporais de 84 vacas Braford e adotou-se como Ăndices de desempenho, a eficiĂȘncia produtiva (EP= mĂ©dia do peso das progĂȘnies ao desmame x nĂșmero de partos/(idade atual - 2)) e a habilidade materna mais provĂĄvel (HMMP) a qual representa a capacidade da vaca em desmamar progĂȘnies mais pesadas. Para classificar o temperamento dos animais utilizou-se uma escala de temperamento e o tempo que os animais levavam para percorrer uma distĂąncia de 6,5 metros, imediatamente apĂłs saĂrem do tronco de contenção atĂ© o final do brete. Observou-se que os animais de tamanho corporal grande foram os que apresentaram as melhores produçÔes no ambiente em estudo, diferindo dos grupos de tamanho corporal mĂ©dio e pequeno, para a HMMP (p= 0,04) e do grupo de tamanho corporal pequeno, para a EP (p= 0,01). Houve uma correlação positiva e altamente significativa entre as medidas corporais e os Ăndices produtivos adotados neste trabalho, com exceção das medidas: comprimento de anca e as alturas das cruzes e de anca. Observou-se que, em animais com redemoinho capilar (independentemente do tipo) acima da linha dos olhos, hĂĄ alta porcentagem de indivĂduos agitados quando comparados aos animais de redemoinho na linha dos olhos e animais sem redemoinhos (p<0,01). Houve uma tendĂȘncia dos animais que apresentaram redemoinho do tipo espiral ter maior escore de temperamento e menor tempo de saĂda do brete. As medidas corporais e a posição do redemoinho capilar facial podem constituir uma ferramenta que venha auxiliar o produtor na tomada de decisĂ”es ao selecionar qual o biotipo mais adequado ao seu sistema de produção.The objective of this work was to seek for tools to aid producers when selecting cows more adapted to the environmental conditions and that present much docile temperament. With this purpose, eleven body measures of 84 Braford cows were taken and were adopted as indexes of efficiency (EP) and of the more probable maternal ability (HMMP). To classify the temperament of the animals a temperament score was used and, also, the time that the animal took to travel a distance of 6.5 m after it was released from the restraining chute. It was observed that the animals of big body size performed better in the studied environment, differing from the groups of medium and small body size, for HMMP (p= 0.04) and from the group of small body size, for EP (p= 0.01). There was a positive and highly significant correlation between the body measures and the productive indexes adopted in this work, except for three measures: hip length, withers and hip heights. It was observed that, on animals with hair whorl (independently of the type) above the line of the eyes, there is a high percentage of agitated individuals when compared to animals with whorls on the line of the eyes and animals without whorls (p<0.01). The body measures and the position of facial hair whorl can constitute a tool to aid the producer when selecting which is the most appropriate biotype for the specific production system