Factors affecting the degree of diarrhea in Canchim calves

Verificaram-se os efeitos de alguns fatores sobre o grau de diarréia de 245 bezerros nascidos em 1982, e de 178 bezerros nascidos em 1983, em um rebanho de gado Canchim. O grau de diarréia foi classificado como: ausência de diarréia, diarréia branda e diarréia forte. A ordem de parição da vaca afetou (P < 0,01) somente o grau de diarréia dos bezerros nascidos em 1983. Os bezerros filhos de vacas primíparas foram os que apresentaram maior grau. O sexo, a cor da pelagem, e o peso ao nascimento do bezerro não apresentaram qualquer efeito, enquanto os efeitos linear e quadrático do dia de nascimento apresentaram-se altamente significativos (P < 0,01). O menor grau de diarréia ocorreu nos bezerros nascidos em julho. As medidas dos tetos (comprimento e circunferência) e a produção de leite das vacas não influenciaram o grau de diarréia, o mesmo ocorrendo com a quantidade de anticorpos presentes no sangue da vaca e do bezerro. Alta correlação positiva entre anticorpos no sangue do bezerro e medidas dos tetos da vaca sugerem que maiores estudos deveriam ser desenvolvidos nesta área.The effects of several factors on the degree of diarrhea of 245 calves born in 1982 and 178 calves born in 1983 were studied. The degree of diarrhea was classified as: no diarrhea, mild diarrhea and strong diarrhea. Parity number of the cow affected (P < 0.01) only the degree of diarrhea of those calves born in 1983. The calves from first parity cows showed higher degree of diarrhea. Sex, color and birth weight of the calves showed no effects on the degree of diarrhea. The linear and quadratic effects of day of birth were highly significant (P < 0.01), and the calves born in July showed less diarrhea. Teat measurements (length and circumference) and milk production of the cows had no effect on the degree of diarrhea, the same happening with the amount of antibodies in the blood of the cow and calf. A high positive correlation between the amounts of antibodies in the blood of the cow and of the calf, and high negative correlations between the amount of antibodies in the blood of the calf and teat measurements suggest that more detailed studies on this area should be undertaken

Evaluation of frozen bull semen. Quick and slow thermoresistance tests: effects on fertility

It was studied the effect of frozen bull semen after thawing and incubation at 45 °C during one hour or at 38 °C during 5 hours (Quick and Slow Thermoresistance Tests), on fertility of beef cows. Treatment 1 included 6 groups of 10 females inseminated with semen showing 20% or plus of progressive motility on quick test and less than 20% on slow test. Treatment 2 (control) included 5 groups of 10 and 1 group of 9 females inseminated with semen showing 20% of progressive motility on slow test and any value on quick test. Only one straw was utilized per estrus, admitted up to 3 repetitions. Pregnancy diagnosis was made by rectal palpation, 60 days after A.I.. Satisfactory results in pregnancy rates were obtained in both treatments (QTT/Q = 0.793 + ou - 0.05 and STT/S = 0.875 + ou - 0.05) with no statistical differences (P&gt;0.05) between them. There was no statistical differences in pregnancy rates of cows inseminated with semen showing motility from 20 to 50% after incubation at 45 °C for one hour.0 objetivo do presente trabalho foi avaliar a eficiência de sêmen congelado, submetido às provas rápida (45 °C/1 hora) e lenta (38 °C/5 horas) de termoresistência, sobre a fertilidade de fêmeas da espécie bovina. Cento e dezenove vacas foram selecionadas e divididas em 2 tratamentos. No tratamento 1 foram incluídos 6 grupos de 10 fêmeas, inseminadas com material cuja análise laboratorial revelou motilidade espermática progressiva superior ou igual a 20%, na prova rápida e valor menor a 20% na prova lenta. O tratamento 2 (controle) utilizou 59 vacas distribuídas em 5 grupos de 10 e un grupo de 9, inseminadas com material que, na prova lenta, apresentou 20% de motilidade espermática progressiva e qualquer valor na prova rápida. Apenas uma palheta foi utilizada por estro, tolerando-se até 3 repetições de cio. 0 diagnóstico de gestação foi realizado por palpação retal, cerca de 60 dias após a última inseminação artificial. Resultados satisfatórios foram alcançados nas taxas de prenhez (TTR/R = 0,793 + ou - 0,05 e TTR/L = 0,875 + ou - 0,05), não havendo diferença estatística (P&gt;0,05) quanto ao tipo de provas do termo-resistência. Não houve diferença significativa (P&gt;0,05) de prenhez de fêmeas insentinadas com material sibmetido ao teste de termo-resistência rápido, quando a motilidade espermática variou de 20 a 50%

Calving interval of canchim cows

Foram estudados 1.095 intervalos entre partos de 224 vacas 5/8 Charolês – 3/8 Zebu e 318 intervalos de 170 vacas Canchim. O mês de início do intervalo influenciou significativamente (P<0,01) os intervalos de ambos os grupos genéticos, enquanto que o ano do início do intervalo (P<0,01) e a ordem do intervalo (P<0,05) somente influenciaram o intervalo entre partos do grupo genético 5/8 Charolês – 3/8 Zebu. Os intervalos foram, em geral, mais curtos quando o primeiro parto do intervalo ocorreu de abril a outubro. O primeiro intervalo foi mais longo, havendo uma tendência de encurtamento até o último intervalo estudado. O sexo do bezerro e a idade ao primeiro parto não tiveram influência significativa sobre os intervalos entre partos. As médias dos intervalos entre partos foram de 405,2 dias para as vacas Canchim e 407 dias para as vacas 5/8 Charolês - 3/8 Zebu. Estimativas de herdabilidade de, na mesma ordem, 0,045 ± 0,100 e 0,041 ± 0,142 sugerem pouco campo para reduzir o Intervalo entre-partos pela seleção. Estimativas de repetibilidade de 0,171 ± 0,080 para as vacas Canchim e 0,203 ± 0,031 para as vacas 5/8 Charolês – 3/8 Zebu indicam, contudo, que existe algum efeito permanente, hereditário ou de ambiente, responsável por diferenças permanentes entre vacas.The 1.095 calving intervals of 224 5/8 Charolais.3/8 Zebu cows and 318 intervals of 170 Canchim cows were studied. Month of the beginning of the interval affected (P<0.01) the intervals from both genetic groups, while year (P<0.01) and interval number (P<0.05) affected only the intervals of the 5/8 Charolais -3/8 Zebu cows. The intervals were, in general, shorter when the first calving of the interval occurred during the dry season (April to October). The first interval was the longest, and there was a tendency to shorten up to the last interval studied. Sex of calf and age at first calving had no effect on calving interval. The least squares means were, 405.2 days for the Canchim and 407 days for the 5/8 Charolais - 3/8 Zebu cows. Heritability estimates of, in the same order, 0.045 ± 0.100 and 0.041 ± 0.142, suggest that there is no scope for improving calving interval through selection. Repeatability estimates of 0.171 ± 0.080 for the Canchim and of 0.203 ± 0.031 for the 5/8 Charolais- 3/8 Zebu cows, indicate, however, that there is some permanent effect, hereditary or environmental, responsible for permanent differences among cows

Heritability of age at first calving in Canchim cows

Foram estudadas as idades ao primeiro parto de 233 vacas 5/8 Charolês -3/8 Zebu e 266 vacas Canchim, criadas nas fazendas São Jorge e Guará, situadas, respectivamente, nos municípios de Cedral e Guzolândia, no Estado de São Paulo. Os modelos estatísticos utilizados nas análises de variância incluíram os efeitos fixos de ano e mês de nascimento da vaca e sexo do bezerro, além dos efeitos aleatórios do pai da vaca. Nenhum dos efeitos influenciou significativamente a idade ao primeiro parto das vacas. As médias estimadas ao primeiro parto foram de 1003,83 ± 12,43 dias (33,00 ±0,41 meses) e 1022,54 ± 12,99 dias (33,62 ± 0,43 meses), respectivamente para as vacas 5/8 Charolês - 3/8 zebu e Canchim - As estimativas de herdabilidade, obtidas pela correlação intraclasse entre meias-irmãs paternas foram, na mesma ordem, -0,066 ± 0,042 e -0,032 ± 0,108, indicando que, nas condições do presente trabalho, o progresso genético pela seleção deve ser praticamente nulo.The age at first calving of 233 5/8 Charolais – 3/8 Zebu (sired by Charolais bulls) and 266 Canchim (5/8 Charolais – 3/8 Zebu) cows, raised in the State of São Paulo, were studied. Analyses of variance, including the fixed effects of year and month of birth of cow and sex of calf, and the random effects of sire of cow, were utilized to analyze the data. None of the effects included in the models affected significantly age at first calving. Least squares means for age at first calving were 1003.83 ± 12.43 days (33.00 ± 0.41 months) and 1022.54 ± 12.99 days (33.63 ± 0.43 months) for the 5/8 Charolais - 318 Zebu and Canchim cows, respectively. Heritability estimates, obtained by the paternal half-sister method, were in the same order, -0.066 ± 0042 and -0.032 ± 0.108, suggesting that, under the conditions of this study, genetic progress by selection would be practically zero

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 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 or ganism 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%–18% of the most ne glected 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 lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 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,18,19 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%–18% 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

Correlações genéticas de características de tamanho corporal e condição corporal com características de eficiência produtiva de fêmeas da raça Canchim

The objectives of this study were to obtain heritability estimates for number (NBZ10 and NBZT) and kilograms (QBD10 and QBDT) of calves weaned up to ten years of age and during herd life, kilograms of calves weaned per year in herd (QTPR) and their genetic correlations with culling age, ages at first, at second and at third calving, adjusted and unadjusted weights for condition score, body size indexes and condition score at first mating, at first calving and at mature age. Variance and covariance components were estimated by REML using univariate and bivariate models including the fixed effect of contemporary group and additive direct genetic and residual as random effects. Heritability estimates obtained from univariate analyses were 0.10 ± 0.05 (NBZT), 0.10 ± 0.03 (QBDT), 0.12 ± 0.05 (NBZ10), 0.13 ± 0.05 (QBD10) and 0.15 ± 0.05 (QTPR) and indicate low response by selection on these traits. Genetic correlation estimate suggest that selection for reducing age at first calving will not improve cow productivity. Selection for increasing mature weight will reduce kilograms of calves weaned per year in herd and the number of calves weaned up to ten years of age and during herd life. Selection on body size indexes and on cow weights adjusted for condition score may result in similar correlated responses in productive traits of cows, which would be higher than those from selection on unadjusted cow weights. © 2008 Sociedade Brasileira de Zootecnia.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq