Physiological and behavioural parameters of broiler chicks grown under different heating systems

Received: December 1st, 2022 ; Accepted: March 29th, 2023 ; Published: April 24th , 2023 ; Correspondence: [email protected] study aimed to compare the internal environment, physiological variables, and behavioural responses of chicks under two different heating systems. The experiment was performed in two commercial broiler houses located in Brazil, where 28,000 male Cobb chicks were housed during the first three weeks of life. One of the broiler houses was heated by an industrial indirect-fired biomass furnace (S1). In addition, another heating system consisting of two furnaces for indirect heating of the air using biomass (wood) as fuel, built by hand with bricks, mud, and dung on an iron structure (S2), was tested. Measurements of the dry bulb temperature (tdb), dew point temperature (tdp), and relative air humidity (RH) were performed. Subsequently, the temperature-humidity index (THI) was calculated. In addition, the physiological variables of the respiratory rate (RR) and cloacal temperature (tcloacal) were measured three times a day (8:00 am, 2:00 pm, and 6:00 pm) in four chicks. The behaviours were grouped by dendrograms, in which the similarity of these data was qualified. During the second and third weeks of life, the THI values were below the recommended range. The RR and tcloacal data were below the recommended comfort values, which may be an indicator that the chicks were subjected to cold conditions. Regarding their behaviour, the chicks exhibited calm, feeding, and sleepy behaviours most of the time. Problems in the heating system inside the broiler house could be observed, possibly affecting the chicks’ thermal comfort and welfare, which consequently can result in productive and economic losses

Use of slate to built swine nursery cells: II - thermal environment and noise evaluation

Este trabalho teve o objetivo de avaliar o ambiente t?rmico e o ru?do em celas de maternidade para su?nos com divis?rias de alvenaria ou com rochas de ard?sia. Para as medidas das vari?veis de conforto t?rmico e de ru?dos, utilizaram-se de term?metros e decibel?metro. No interior das celas e para a an?lise estat?stica, foram usados doze matrizes e cento e trinta e nove leit?es, distribu?dos em delineamento em blocos casualizados, em esquema de parcelas subdivididas. Os resultados mostraram que, no per?odo da manh?, em ambos os tratamentos, as condi??es de conforto t?rmico foram mais adequadas para as matrizes, enquanto no per?odo da tarde, mais adequadas para os leit?es; com rela??o ao ru?do, este foi menor nas celas de alvenaria. De forma geral, o ambiente no interior das celas constru?das em ard?sia apresentou umidade relativa mais baixa, e ITGU e temperatura mais elevada que as celas constru?das em alvenaria. O n?vel de ru?dos permaneceu dentro dos limites considerados ideais para su?nos em ambos os tratamentos.Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)Empresa de Pesquisa Agropecu?ria de Minas Gerais (EPAMIG)Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)The aim of the present study was to evaluate the thermal environment and noise levels in swine farrowing cells built with masonry or slate. Thermometers and sound level meter equipment were used to measure the thermal comfort variables. Inside the cells and for the statistical analysis, twelve sows and one hundred thirty-nine piglets were used, distributed in a randomized blocks design in a split-plot arrangement. The results showed that in the morning, in both treatments, the thermal comfort conditions were more suitable for sows, while in the afternoon it was more suitable for piglets. The noise was lower in the masonry cells. Overall, the environment inside in the cells built with slate presented lower relative humidity and, higher BGHI and temperature than those built with masonry. The noise level remained within the thresholds considered as ideal for swine in both treatments

Aduba??o nitrogenada na forma de cama sobreposta de su?no e seus efeitos nos atributos de um Neossolo Quartzar?nico

Objetivou-se com o presente trabalho avaliar os efeitos da aduba??o nitrogenada na forma de cama sobreposta de su?no sobre os atributos de um Neossolo Quartzar?nico. O composto org?nico utilizado foi a cama sobreposta, feita com casca-de-arroz, proveniente de uma granja comercial de su?nos em sistema de termina??o. As amostras de cama sobreposta foram retiradas em v?rios pontos da instala??o, visando a obter-se amostra composta representativa, ap?s o que foi fracionada em peneira de 2,0 mm e submetida a uma compostagem adicional de 50 dias. Na sequ?ncia, foram realizadas an?lises de valor agron?mico. O delineamento experimental foi o inteiramente casualizado. Os tratamentos constitu?ram-se das dosagens de 0; 75; 150 e 300 mg dm-3 de N na forma de cama sobreposta, bem como um tratamento adicional com sulfato de am?nio na dose de 150 mg dm-3 de N. O per?odo experimental em casa de vegeta??o foi de 45 dias, onde se cultivou o solo com milho. Finalizado o experimento, procedeu-se a nova an?lise dos atributos do solo. Pelos resultados obtidos, notou-se que a aduba??o org?nica com cama sobreposta proporcionou aumentos significativos nos teores de pot?ssio, na soma de bases, na CTC efetiva, na CTC a pH 7,0 e na porcentagem de satura??o por bases.Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)Empresa de Pesquisa Agropecu?ria de Minas Gerais (EPAMIG)Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)The objective of this study was to evaluate the effects of the nitrogen fertilization in the form of swine deep bed in the properties of a quartz-sand neosol. The organic compound used was the deep bed made with rice hulls, from a commercial swine finishing system farm. Deep bed samples have been collected at various points in the installation in order to obtain a representative composite sample which has been fractionated in a 2.0 mm sieve and submitted to a 50-day maturation period. Then, agronomic value analyses were done. The experimental design was completely randomized. The treatments consisted of 0; 75; 150 and 300 mg dm-3 of N doses of deep bed as well as an additional treatment with ammonium sulfate at a 150 mg dm-3 of N. The experimental period in the greenhouse was 45 days, where the soil was cultivated with maize. After the experiment completion, further soil properties analyses were done. From the results, it was noted that the organic fertilization with deep bed provided a significant increase in the levels of potassium, in the sum of the bases, in the effective CEC, in the CEC at pH 7.0 and in the percentage of saturation