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Andrea R. Bueno Ribeiro

Bio: Andrea R. Bueno Ribeiro is an academic researcher. The author has contributed to research in topics: Sire. The author has an hindex of 2, co-authored 3 publications receiving 5 citations.
Topics: Sire

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Journal ArticleDOI
TL;DR: Female calves in subtropical environmental need extra care when born on rainy days, especially during the first hours of the day, especially if they are calves raised in intensive production systems.
Abstract: Effects of sire breed-grazing system and environmental factors on the first activities of high grade Nellore and crossbred Canchim × Nellore, Angus × Nellore, and Simmental × Nellore calves raised in intensive production systems and high grade Nellore calves raised in an extensive production system, after birth, were studied During 2 years, 185 calves were observed from birth until the end of first suckling, and the following variables were estimated: duration of maternal attention (cow to calf) during the first 15 min after calving, latency to first attempt to stand up, latency to stand up, latency to first suckling, duration of first suckling and the interval from standing to suckling Data were analyzed by least squares methods, with models that included fixed effects of year and time of the year of birth (March–April (early autumn) and May–June (late autumn)), sire breed-grazing system (Sy), sex of calf (Se), category of cow (primiparous and pluriparous), time of birth, Sy × Se, year × Sy and year × time of the year interactions and the covariates weight of calf, rainfall, air temperature and relative humidity in the day of birth Calves born from 6:00 to 8:00 h presented the longest latencies to first stand up (403 ± 51 min) and the shortest occur from 14:00 to 16:00 h (158 ± 27 min) (P 005) any behaviour variable studied As regard to sex differences, female calves did take less (P

4 citations

Journal ArticleDOI
TL;DR: The influence of environmental parameters on the physiological responses of purebred and crossbred Nellore calves born in a subtropical region was studied and PT level was significantly higher in NR calves than in NI ones.
Abstract: Estudou-se a influencia de fatores climaticos sobre as respostas fisiologicas de bezerros, puros e cruzados, filhos de vacas da raca Nelore ou de alta mesticagem de Nelore acasaladas com touros das racas Aberdeen Angus (AN), Simental (SN), Canchim (CN) e Nelore (NI e NR). Os bezerros AN, SN, CN e NI foram mantidos em sistema rotacionado intensivo, enquanto o grupo NR foi mantido em sistema extensivo. Os bezerros foram observados de forma direta desde o nascimento ate a primeira mamada, medindo-se a latencia para a primeira mamada (LM). Aproximadamente 24 horas apos o parto, coletaram-se amostras de sangue do bezerro para as dosagens de proteina total (PT), glicose (Gli), triiodotironina (T3), tiroxina (T4), relacao T4:T3, cortisol (Cort) e imunoglobulina G (IgGb), alem das medidas de temperatura retal do bezerro (TR) e dos pesos de vacas e bezerros. Para analise dos efeitos de clima, foram tomadas no dia do nascimento as medidas de temperatura do ar (Temp), umidade do ar (UR) e precipitacao (PRE). Os parâmetros fisiologicos foram estudados pelo metodo dos quadrados minimos com modelos que incluiram os efeitos de ano e mes de nascimento, grupo e sexo do bezerro, categoria da vaca e hora do parto e das interacoes ano × grupo e ano × mes de nascimento, alem das covariaveis peso do bezerro, PRE, Temp, UR e LM. Temp mostrou efeito significativo para as concentracoes de T3, T4, T4:T3 e de Cort. Quanto maior Temp, menores as concentracoes de T3 e de Cort e maiores as de T4 e de T4:T3. LM influenciou os niveis de Cort, PT e IgGb, de modo que, quanto maior LM, maior a concentracao de Cort e menor as de IgGb e PT. Tambem houve efeito significativo de grupo do bezerro sobre PT, que foi maior nos bezerros NR que nos bezerros NI.

2 citations

01 Jan 2009
TL;DR: In this paper, principal component analysis (PCA) was used to reduce the dimension of the original data set, reducing it from a set of 16 variables to only four autovectors that explained about 60% of the latent original variation of the data.
Abstract: The objective was to use principal component analysis (PCA) in the evaluation of physiological data related to heat tolerance in 45 beef cattle, being 15 of each genetic group: Nelore (NE) and crossbred Angus x Nelore (TA) and Senepol x Nelore (SN). The experiment was carried out during a heat tolerance test in the summer season. The PCA technique showed to be advantageous in order to reduce the dimension of the original data set, reducing it from a set of 16 variables to only four autovectors, that explained about 60% of the latent original variation of the data. variation,

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Journal ArticleDOI
01 Jan 2019
TL;DR: Subclinical trauma was associated with calving difficulty, decreased vigour and decreased odds of having adequate PI and haptoglobin was not associated with any of the parameters measured.
Abstract: This cross-sectional study quantifies subclinical trauma associated with calving difficulty, calf vigour, and passive immunity (PI) in newborn beef calves. The degree of calving difficulty was categorised as: unassisted, easy assist (one or two people manually pulling to deliver the calf) and difficult assist (more than two people pulling, a fetal extractor (ie, calf jack), or caesarean section). Vigour assessment occurred at 10 minutes and blood sampling at 24 hours after birth in 77 beef calves. The measured blood parameters associated with trauma were creatine kinase (CK), aspartate aminotransferase (AST), and haptoglobin. Serum IgG concentration was measured, and an IgG concentration at least 24 g/l was considered as adequate PI. Calving difficulty was associated with elevated levels of CK (P=0.002) and AST (P=0.01), weak suckle reflex (P=0.001), abnormal mucous membrane colour (P

14 citations

Journal ArticleDOI
TL;DR: A series of observational studies were set up, addressing the mother-offspring relationships of Nelore, Guzerat and Gyr cattle breeds, describing the behaviour of cows and calves around the time of parturition and the underlying factors that affect the calves' survival and development.
Abstract: The knowledge of the interaction between mother and offspring might contribute to enhance the welfare of the offspring and to improve the reproductive efficiency of the cow. However, there is still little information available about such interaction in some cattle breeds. A series of observational studies were set up, addressing the mother-offspring relationships of Nelore, Guzerat and Gyr cattle breeds. Firstly, the behaviour of cows and calves around the time of parturition was described, and then, the underlying factors that affect the calves' survival and development were studied. Special attention was given to the failure or delay in the first suckling. The results together are indicative of genetic variability for some studied variables, indicating the possibility of selection for calf vigour (using latency to stand up and latency to suckle as its indicators) and maternal ability (using percentage of time in contact with the calves), in spite of the estimates of heritability were low and presented high standard deviation for all variables. The individual variability in their suckling behaviour and the efficiency in first suckling cannot be explained by a single isolated underlying factor. By now, there are some results available, although there are many questions without answers. The field is still open for the development of future research.

11 citations

Journal ArticleDOI
23 Sep 2019
TL;DR: For instance, Boff et al. as mentioned in this paper investigated the conforto térmico in ambiente externo at the University of Cachoeira do Sul, Brazil.
Abstract: ANÁLISE BIOCLIMÁTICA E INVESTIGAÇÃO DO CONFORTO TÉRMICO EM AMBIENTE EXTERNO NA REGIÃO CENTRAL DO RS ZANANDRA BOFF DE OLIVEIRA1, ALBERTO EDUARDO KNIES2 Professora adjunta, Coordenadoria Acadêmica, Universidade Federal de Santa Maria Campus em Cachoeira do Sul, Rua Ernesto Barros, nº 1345, Bairro Santo Antônio, cep: 96506-322, Cachoeira do Sul – RS, Brasil. E-mail: Professor adjunto, Universidade Estadual do Rio Grande do Sul Unidade em Cachoeira do Sul, Rua Sete de Setembro, nº 1040, Bairro Santo Centro, cep: 96508-010, Cachoeira do Sul – RS, Brasil. E-mail: RESUMO: o presente trabalho teve como objetivo realizar a análise bioclimática e a investigação do conforto térmico em ambiente externo na região central do RS. Para isso, utilizaram-se os seguintes índices de conforto térmico: índice de temperatura e umidade (ITU) e índice de desconforto humano (IDH). Os dados meteorológicos de temperatura do ar máxima (Tmax) e mínima (Tmin) e umidade relativa do ar máxima (URmax) e mínima (URmin) foram obtidos de uma série de 10 anos (2005-2015) de dados de uma estação meteorológica automática instalada em Santa Maria (RS). A temperatura do ponto de orvalho foi estimada a partir da Tmax e Tmin e da URmin e URmax, respectivamente. Os índices de conforto térmico foram calculados a partir das médias diárias do período (10 anos) para a situação de máximo desconforto térmico que ocorre nos extremos: 1) quando a temperatura do ar é máxima e a umidade relativa do ar é mínima - denominados de ITUmax e IDHmax; 2) quando a temperatura do ar é mínima e a umidade relativa do ar é máxima - denominados de ITUmin e IDHmin. Em função da elevada amplitude térmica mensal (>10ºC<18ºC) e diária (>5ºC<10ºC), os valores dos índices de conforto térmico (ITU e IDH) variam entre 51,5 e 80,4, indicando que a situação de conforto térmico do ambiente externo na região central do RS vai nos extremos de estresse térmico devido ao frio (julho) a estresse térmico devido ao calor (janeiro). No período de maio a outubro o conforto térmico ocorre na Tmax, mas na Tmin a situação é de desconforto a estresse por frio. No período de novembro a fevereiro, o conforto térmico ocorre na Tmin, mas na Tmax ocorre desconforto a estresse térmico por calor. Nos meses de março e abril, o desconforto ocorre tanto por frio quanto por calor. Dessa forma, para a produção zootécnica e para o conforto térmico humano na região central do RS, são necessárias práticas de acondicionamento ambiental que visem a minimização do estresse térmico. Palavra-chaves: índices de conforto térmico; análise bioclimática; amplitude térmica. BIOCLIMATIC ANALYSIS AND RESEARCH OF THERMAL COMFORT IN EXTERNAL ENVIRONMENT IN THE CENTRAL REGION OF RS ABSTRACT: The present work had the aim of performing the bioclimatic analysis and the investigation of the thermal comfort in an external environment in the Central region of RS. For this, the following thermal comfort indexes were used: temperature and humidity index (THI) and human discomfort index (HDI). The maximum air temperature (Tmax) and minimum air temperature (Tmin) and maximum relative humidity (URmax) and minimum air humidity (URmin) were obtained from a series of 10 years (2005 to 2015) of data of an automatic meteorological station installed in Santa Maria - RS. The temperature of the dew point was estimated from the Tmax and Tmin and the URmin and URmax, respectively. The thermal comfort indexes were calculated from the daily average of the period (10 years) for the situation of maximum thermal discomfort that occurs in the extremes: (i) when the air temperature is maximum and the relative humidity of the air is minimal - denominated of THImax and HDImax; (ii) when the air temperature is minimal and the relative humidity of the air is maximum - denominated THImin and HDImin. In function to the high temperature amplitude, monthly (> 10ºC <18ºC) and daily (> 5ºC <10ºC), the values of thermal comfort indexes (THI and HDI) vary from 51.5 to 80.4, indicating that thermal comfort of the external environment in the Central region of RS goes in the extremes of thermal stress due to the cold (July) to the heat stress due to the heat (January). In the period from May to October the thermal comfort occurs in Tmax, but in Tmin the situation is of cold stress discomfort. In the period from November to February, thermal comfort occurs in Tmin, but in Tmax, heat stress discomfort occurs. In the months of March and April the discomfort occurs as much by cold as by heat. Thus, for a zootechnical production and human thermal comfort in the central region of RS, it is necessary to practice environmental conditioning to minimize thermal stress. Keywords: thermal comfort index; bioclimatic analysis; thermal amplitude.

3 citations

Journal ArticleDOI
TL;DR: In this paper , the authors quantified early postpartum nursing behavior of neonatal beef calves and highlighted dam and calf behaviours that may adversely affect milk intake and therefore impact calf survival.
Abstract: Observations of 17 heifer-calf pairs were collected over the first 5 days postpartum (p.p.) to study nursing and maternal behaviour of beef cattle. Cattle were managed in a 6 ha paddock and heifer–calf interactions were determined from both regular visual observations and video recordings. Of 17 potential calves, one was stillborn and 3 died in the first 5 days p.p. associated with dystocia and congenital malformation. Four further potential neonatal calf mortality risks were identified, which included poor calving site selection (n = 1), calf misadventure (n = 1), heifer-calf separation (n = 3) and mismothering (n = 3), with each resulting in distress, physical exhaustion of the calf and impaired nursing. There was marked variation between heifers in the expression of optimal maternal behaviours, with only 39% classified as ‘good’ mothers. Dam terminated nursing bouts were 27% shorter in duration than calf terminated nursing bouts; 29% of heifers terminated nursing bouts at least 50% of the time. Only 68% of observed suckling interactions were considered effective. On average, the nursing behaviour lasted 7.0 min, with sucking making up 54% of the total nursing time, the sucking rate was 2.0 sucks/s, and the calves performed 7.5 teat-switches, 2.4 butts and 0.9 teat-strips per min of nursing. In 67% of nursing interactions, the calves sucked on all four teats. By three days p.p., all calves developed a clear, consistent suckling pattern. Prior to this, the calves had shorter nursing bouts, spent less time nursing and manipulating the udder, paused more, switched teats and butted less, and had a slower sucking rate. The behaviour of some calves (i.e., low teat fidelity and high levels of milk stimulation behaviours) suggested that their dam milk availability was low. This study has quantified early post-partum nursing behaviour of neonatal beef calves and highlighted dam and calf behaviours that may adversely affect milk intake and, therefore, impact calf survival.

2 citations