Calcium levels and calcium: available phosphorus ratios in diets for white egg layers from 42 to 58 weeks of age

The experiment was conducted to determine the nutritional requirement of calcium and the best calcium:available phosphorus ratio for commercial layers at the post-laying peak. A total of 324 Hy-Line W-36 laying hens were utilized in the period from 42 to 58 weeks of age, distributed in a completely randomized design in a 3 × 3 factorial arrangement, composed of three levels of calcium (39, 42 and 45 g/kg) and three calcium:phosphorus ratios (12.12:1; 10.53:1; and 9.30:1), totaling nine treatments with six replications and six birds per experimental unit. There was no significant effect from the calcium levels × calcium:phosphorus ratio interaction for any of the variables studied. The calcium levels and the calcium:phosphorus ratios did not affect the variables performance or egg and bone quality. At the evaluation of the calcium:phosphorus balance, as the levels of calcium of the diet were raised, the intake of calcium and phosphorus and the contents of mineral matter and calcium in the excreta increased linearly, and the retention of calcium by birds decreased linearly. With the reduction of the calcium:phosphorus ratios of the diet, intake, retention and excretion of phosphorus by layers increased. Diets containing calcium at 39 g/kg and a calcium:phosphorus ratio of 12.12:1, corresponding to an increase in calcium of 3.51 g/bird/day and available phosphorus of 289 mg/bird/day, meet the requirements of calcium and available phosphorus of white egg layers in the period from 42 to 58 weeks of age

Locomotor problems in broilers reared on new and re-used litter

Two field trials were conducted to assess locomotor problems in broilers. Males and females broilers were used from two commercial strains reared on two different litter materials, new and re-used. In the first experiment (E1) rice husks and wood shavings were used as new litter, and in the second experiment (E2) the same litter was re-used. A batch of one-day-old chicks (2968) was reared randomly distributed in experimental pens, in a 2x2x2 factorial scheme (two genetic strains, two sexes and two litter materials). The same fodder and water were available to all birds <em>ad libitum</em>. Broilers locomotion problems were evaluated using the characteristics of gait score, incidence of <em>valgus</em> and <em>varus</em>, foot-pad lesions, degeneration, femoral, tibial dyschondroplasia, spondylolisthesis and breast calluses. The number of birds with high gait score was less than 30% in the two experiments. Males presented higher gait score (GS) (28.46% GS 1 and 2 compared to females, 20.98%); greater incidence of angular deformities (26.62% with <em>valgus</em> compared to 14.71% of the female); and femoral degenerative joint lesions (70.83% in average, compared to 55.16% of the female), and the correlation between these traits varied from 0.18 to 0.87 (P&lt;0.05). There was an increase of foot-pad lesions in re-used litter leading to poor welfare. The use of rice husks in deep litter for broiler production might be a viable alternative of wood shavings

EQUILÍBRIO E PROBLEMAS LOCOMOTORES EM FRANGOS DE CORTE / EQUILIBRIUM CONDITION AND LOCOMOTION PROBLEMS IN BROILERS

O crescimento de uma ave depende particularmente do desenvolvimento muscular e do tecido ósseo. Atualmente em frangos de corte o crescimento muscular é extremamente elevado enquanto seu suporte esquelético ainda se encontra muito imaturo, tendo como consequências o aparecimento de afecções locomotoras entre outras. Com os avanços no melhoramento genético avícola, verifica-se que a forma de caminhar e a condição de equilíbrio foram influenciadas negativamente, causando dificuldades de locomoção nesses animais. A presente revisão apresenta as principais desordens locomotoras que acometem as aves de produção e alguns dos fatores que as influenciam, assim como o impacto que elas causam na avicultura de corte.  </p

Photostimulation of Japanese quail

To adapt commercial poultry production to a new scenario of energy savings and to develop specific practices for quail production aimed at reducing costs while maintaining or improving productivity, four experiments were conducted. In the first experiment, birds were allocated to four treatments (photoperiod duration): T1: 14L:10D; T2: 15L:9D; T3: 16L:8D; and T4: 17L:7D. In the second experiment, birds were subjected to four levels of brightness: T1: 5 lux; T2: 10 lux; T3: 15 lux; and T4: 22 lux (control). In the third experiment, four types of lamps were evaluated: T1: compact fluorescent lamp (color temperature: 6,500K); T2: compact fluorescent lamp (color temperature: 2,700K); T3: incandescent lamp; and T4: yellow LED. In the last experiment, four lighting programs were compared: T1: continuous program (control), in which there was a single photoperiod of 15 h; the other treatments consisted of intermittent lighting programs, as follows: T2: 1 h of light provided 1 h after dusk; T3: 1 h of light provided 2 h before dawn; T4: half an hour of light provided 1 h after dusk and half an hour of light provided 1.5 h before dawn. In each experiment, 1,296 Japanese quail were evaluated for four 28-d cycles, totaling 112 experimental days. A completely randomized experimental design of 4 treatments with 12 replicates of 27 birds each was applied in all trials. Performance and egg quality were evaluated in each experiment. Higher egg production and adequate egg quality, as well as energy savings, can be obtained with Japanese quail using compact fluorescent lamps or LEDs and a photoperiod of 15 h/d supplied using an intermittent lighting program, with 1 h of artificial light 2 h before dawn at a brightness of 5 lux.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FMVZ, Dept Anim Prod, Unesp Botucatu, SP, BrazilDepartment of Animal Production, FMVZ, Unesp-Botucatu/SP, Brazi

Impact of lameness on broiler well-being

Various degrees of lameness were compared among male broilers ranging in age from 28 to 49 d that had been randomly selected from a commercial farm. Gait scores were given to the broilers while they walked on a force measurement platform system, and the force exerted by their feet was measured and compared in 2 distinct conditions: with and without administration of an analgesic. Postmortem femoral degenerative lesions were observed, and the femur strength in response to a compression load was measured and compared. Results showed a difference in the peak vertical forces of the right and left feet before and after medication. The researchers also found that as BW increased, the locomotion ability of broilers tended to decrease. After birds received the analgesic, the peak vertical force increased among the more severely lame broilers at 35 to 49 d of age and their walking speed was decreased, indicating that they might have felt pain during locomotion. No difference was found between the femur (right and left) strength in response to a compression load; however, the results showed that femurs of 28-d-old birds were less resistant to compression (P < 0.05) than those of older broilers. The foot force platform was a useful tool for assessing the walking ability of broilers.State Univ Campinas UNICAMP, Sch Agr Engn, Campinas, SP, BrazilState Univ São Paulo UNESP, Sch Vet Med & Anim Sci, Botucatu, SP, BrazilRes Grp Biosyst Technol UNICAMP, Ctr Technol, Campinas, SP, BrazilState Univ São Paulo UNESP, Sch Vet Med & Anim Sci, Botucatu, SP, Brazi

The use of infrared thermography in the identification of pododermatitis in broilers

ABSTRACT International trade in broiler’ feet, mainly to Asian markets, has demanded better quality control. The objective of this research was to study the suitability of using chicken footpad surface temperature to determine early lesions of pododermatitis. The project was conducted in two houses A1 and A2) in a commercial farm during one production flock. A1 had reused litter of wood shavings and rice hulls, and A2 had a new litter of sawdust. Both houses had positive pressure ventilation. The inner area of the poultry was virtually divided into three quadrants. The footpads were checked for the feet quality, and a degree of pododermatitis was awarded. Thermal images were made to test the surface temperature of the foot and identify inflammation in a total of 30 birds per house, at ages 5, 19, 29, 28 and 40 days of grow-out. Conditions of the rearing environment as well as the surface temperature of the litter, litter moisture, and degree of compression, were recorded. The environment within the houses did not differ. The surface temperatures of the footpad did not differ between the groups. The minimum footpad surface temperatures within the scores were similar, except for the score 3, which did not occur in A1. There was a prevalence of severe injury in the house with a new litter