Diurnal behaviors and herd characteristics of dairy cows housed in a compost-bedded pack barn system under hot and humid conditions.

With international demand for production systems aimed at thermal comfort and animal welfare, milk producers have become increasingly interested in compost barns. However, doubts about the behavioral aspects of cows in tropical and subtropical climates remain, because the compost barn system offers a larger bed area per animal at a lower stocking rate. The objective of this study was to evaluate whether the diurnal behaviors, hygiene and lameness of crossbred dairy cows are influenced by different number of lactations when housed in a compost-bedded pack barn system under hot and humid conditions. Crossbred cows (Holstein and Jersey), which were divided into two treatments based on number of lactations (primiparous and multiparous cows), were evaluated during lactation (n=12). The study was conducted from September 2015 to February 2016 in a compost barn in the southwest region of the state of Paraná, Brazil. Daytime behavior was observed between milking schedules using focal observations with 0/1 sampling. Cow hygiene and lameness were evaluated using subjective scores ranging from 1 to 4 and 1 to 5, respectively. Animal behavior and welfare was analyzed using Bayesian inference with a mixed effects model. The probabilities of dyspnea and pushing behaviors were higher (P<0.05) in multiparous cows, and the probability increased during the hottest hours of the day. For both multiparous and primiparous cows, the agonistic behaviors of pushing, butting and chasing peaked during the afternoon. Eating behaviors had the highest likelihood values (0.8 at 0800 h). The cows preferred to remain lying down in the morning, while rest and standing rumination were preferred in the afternoon. Primiparous cows were cleaner than multiparous cows, and the hygiene score for this group was significantly lower (P<0.05). The hygiene and lameness scores for all animals were low, and the highest scores were 1 and 2. In conclusion, multiparous cows exhibited more frequent agonistic behaviors during the hottest hours of the day. Regarding hygiene and lameness scores, multiparous cows exhibited a higher degree of dirtiness compared with the primiparous cows.

Influência das condições térmicas do galpão de espera climatizado na mortalidade pré-abate de frangos de corte / The influence of thermal conditions from an environmentally controlled preslaughter lairage on mortality of broiler chickens

Avaliou-se o efeito das condições ambientais da espera pré-abate na mortalidade de frangos de corte, mantidos em galpão climatizado em um abatedouro comercial. Foram avaliados 215 caminhões de transporte de um abatedouro comercial quanto ao número de aves mortas durante as operações pré-abate e à temperatura retal dos animais em condição de espera no abatedouro. Os dados foram obtidos no galpão de espera climatizado por meio de ventiladores e nebulizadores, em diferentes períodos: manhã, tarde e noite. As variáveis térmicas, distância, tempo de espera e densidade de aves por caixa foram consideradas na análise. Destacaram-se os efeitos da temperatura, da umidade relativa e do tempo de espera na variação tanto do número de aves mortas por caminhão quanto da temperatura retal dos animais. Com relação à interação entre temperatura e umidade relativa interna do galpão de espera, houve eficiência do ambiente climatizado no abatedouro quanto à diminuição do número de aves mortas. A climatização foi mais expressiva na redução do número de aves mortas e da temperatura retal quando a temperatura do galpão de espera estava entre 21 e 24°C, principalmente em condições de umidade relativa interna em torno de 70%. Nessas condições climatizadas, o tempo de espera acima de duas horas proporcionou maior conforto às aves.

The effect of environment conditions of preslaughter lairage on broiler mortality was assessed in the present study. Daily preslaughter data from 215 broiler flocks were recorded regarding the number of dead chickens during preslaughter operations and rectal temperature of broilers submitted to a lairage environment prior to slaughtering. A holding area at a slaughterhouse with environmental control was assessed. The thermal variables, distance between farms and slaughterhouse, lairage time and density of birds per cage was considered in this analysis. The effect of dry-bulb temperature, relative humidity and lairage time on death before arrival and rectal temperature was highlighted in this assessment. Regarding the interaction between temperature and inside relative humidity, a decrease in preslaughter mortality was observed due to exposure to a controlled environment. The environment control promoted an expressive reduction in dead birds and rectal temperature when the temperature inside the holding area was between 21 and 24 °C, mainly with inside relative humidity around 70%. In these environment control conditions lairage above 2 hours was necessary to reduce the thermal stress of birds.

Termorregulação de pintos de um dia submetidos a ambiente térmico simulado de transporte / Thermoregulation of day-old chickens submitted to simulated transport thermal environment

Objetivou-se, por meio deste trabalho, avaliar a termorregulação de pintos de um dia, mantidos em caixas de transporte, sob condição térmica simulada de transporte. Dois experimentos replicados executados em dias diferentes foram conduzidos em câmara climática. Para cada um dos experimentos, foram utilizados 360 pintos de um dia. Esses animais foram submetidos às condições de frio, conforto e calor, durante uma hora em cada tratamento. Os animais foram mantidos em caixas de transporte de pintos de um dia com quatro compartimentos, sendo cada um deles com 10 animais, totalizando 40 animais por caixa. Foram utilizadas três caixas empilhadas, simulando o que ocorre no caminhão de transporte. Para avaliação fisiológica, foram realizadas as seguintes medidas: frequência respiratória, peso, temperaturas superficial e cloacal. No geral, o posicionamento das caixas não alterou profundamente o conforto térmico dos pintos de um dia. Com relação às faixas térmicas, a condição de frio foi a que mais afetou as respostas fisiológicas, com destaque para as temperaturas superficial média e cloacal. No entanto, com o aumento do tempo de exposição, possivelmente o tratamento térmico por calor possa ter mais efeito sobre a termorregulação desses animais.

An experiment was conducted to assess the thermoregulation of day-old chickens, placed in transport boxes, under simulated transport thermal condition. Two replicated trials were done in two different days in a windowless environmentally controlled chamber. For each one, a total of 360 one-day-old broiler chicks were used. These animals were submitted to three thermal conditions (cold, thermoneutral and heat), for 1 h each. The birds were placed in boxes for day-old chick transport, divided in 40 chicks per box, with three boxes stacked vertically, for each treatment (120 chicks per treatment). Body weight, respiratory frequency, mean surface and cloacal temperature were monitored in a sample of 20 animals per box, with measurements were made before and after the treatments. The box placement had a negligible effect on the thermal comfort of birds. The mean surface and cloacal temperature responses were markedly affected by the cold treatment. However, with an increasing exposure time, the heat treatment might possibly have a clear evidence on the thermoregulation of day-old chickens.

Preslaughter mortality of broilers in relation to lairage and season in a subtropical climate.

The preslaughter handling and transport of broilers are stressful operations that might affect welfare and meat quality and could increase numbers of deaths before slaughter. However, the influence of thermal factors during transportation and lairage at slaughterhouses is complex in subtropical regions, where increasing temperature and high RH are the major concerns regarding animal survival before slaughter. In this study we assessed the influence of a controlled lairage environment on preslaughter mortality rates of broiler chickens that were transported during different seasons of the year and had varying lairage times in the subtropical climate. Preslaughter data from 13,937 broiler flocks were recorded daily during 2006 in a commercial slaughterhouse in southeastern Brazil. The main factors that influenced daily mortality rate were mean dry bulb temperature and RH, lairage time, daily periods, density of broilers per crate, season of the year, stocking density per lorry, transport time, and distance between farms and slaughterhouse. A holding area at the slaughterhouse with environmental control was assessed. Using a double GLM for mean and dispersion modeling, the seasons were found to have significant effects (P < 0.05) on average mortality rates. The highest incidence was observed in summer (0.42%), followed by spring (0.39%), winter (0.28%), and autumn (0.23%). A decrease of preslaughter mortality of broilers during summer (P < 0.05) was observed when the lairage time was increased, mainly after 1 h of exposure to a controlled environment. Thus, lairage for 3 to 4 h in a controlled lairage environment during the summer and spring is necessary to reduce the thermal load of broiler chickens.

Calculation of MP2 and coupled-cluster molecular properties using the q-integral method.

The main purpose of this paper is to report results of quantum mechanical calculation of the H(2) system using the q-Integral method with correlation corrections to the SCF (Self Consistent Field) wave functions included through the Møller-Plesset second-order perturbation (MP(2)) and Coupled-Cluster (CC) theory. Using the q-Integral method, we evaluated potential energy curves, rovibrational spectroscopy constants, rovibrational spectra, interatomic equilibrium distance and longitudinal static hyper(polarizability). All calculations were carried out through the STO-3G, STO-6G, and double-zeta (DZV) atomic basis set. The q-Integral method was implemented in the source code of the general ab initio quantum chemistry package GAMESS.