RESUMEN
Commercial equipment used by the turkey industry at hatch sterilizes the germinal tissue of the claw with microwave energy and the beak tissue with infrared energy. This effectively trims the claws and beaks of the birds. Two strains of Leghorn chicks (1,200 each strain) were utilized to test this technique on chickens. Half were subjected to the claw reduction (RC) technique at hatch, and half retained intact claws (IC). The beaks of one-third of the birds in the claw treatments were reduced (BT) at hatch using the infrared technique, one-third were precision trimmed at 7 d, and one-third were not trimmed (IB). Body weight, weight gain, feed intake, feed conversion, mortality, and fearfulness were measured. Rearing followed standard commercial feeding and husbandry procedures. The RC birds had significantly lower BW, except from 3 to 6 wk, and had significantly lower feed consumption from 8 to 18 wk. The 1 d BT birds experienced significantly lower BW from 3 to 14 wk and ate less total feed by 4 wk. Mortality was less than 2.1% for all treatments. From 6 to 8 wk, fearfulness score (a subjective scale of 1 to 10) peaked at 8 to 10 for IC birds and 3 to 4 for RC birds. By 16 to 18 wk, fearfulness score subsided to 2 to 3 for RC and 6 to 8 for IC. Beak trimming and reduction of claw growth at hatch allowed pullets to be grown to sexual maturity on less feed and with a lower level of observed fearfulness using standard husbandry practices.
Asunto(s)
Agricultura/métodos , Pico , Pollos/crecimiento & desarrollo , Miedo , Pezuñas y Garras , Esterilización/métodos , Agricultura/economía , Alimentación Animal/economía , Animales , Pico/efectos de la radiación , Conducta Animal , Costos y Análisis de Costo , Femenino , Pezuñas y Garras/efectos de la radiación , Rayos Infrarrojos , Microondas , OviposiciónRESUMEN
The effects of dietary nickel (0, 25, 50, 75, 100, and 150 mg/kg) on the bone strength characteristics and performance parameters of male broilers were investigated. Broilers were housed in either cages or floor pens. At 6 wk of age, the shear fracture energy of the tibia from the caged birds increased when the basal diet was supplemented with 25 mg of dietary nickel per kilogram of feed. The shear force, stress, and fracture energy of the radius from the caged birds also increased at 25 mg/kg nickel. Dietary nickel had no effect on bird body weight, but the caged broilers (2,161 g) were heavier than the floor birds (2,005 g). Nickel had no effect on the strength characteristics of the tibia from the floor birds. Percent tibia bone ash, a measure of bone density, was not influenced by dietary nickel, but the tibia ash of the floor birds was greater than that of the caged birds. Overall, the data indicates that adding 25 mg/kg of dietary nickel to a poultry diet will have a positive influence on bone strength characteristics and performance.
Asunto(s)
Huesos/efectos de los fármacos , Huesos/fisiología , Níquel/farmacología , Animales , Peso Corporal/efectos de los fármacos , Pollos , Suplementos Dietéticos , Ingestión de Alimentos/efectos de los fármacos , Vivienda para Animales , Masculino , Estrés Mecánico , Tibia/anatomía & histología , Tibia/efectos de los fármacos , Tibia/fisiologíaRESUMEN
1. The effects of dietary boron (0, 50, 100, 200, and 400 mg/kg) on bone strength characteristics and egg production of white leghorn layers were investigated. 2. The shear fracture energy increased in the tibia and radius at 72 weeks for birds started on the 200 mg/kg supplement at 32 weeks of age. 3. The shear force, stress, and fracture energy of the tibia and radius increased for the non-egg producing birds at 72 weeks. 4. Bird body weight, food consumption, egg weight, and egg production all decreased at 400 mg/kg boron. 5. Boron concentrations in the breast, liver, thigh and bone tissue increased with increasing concentrations of supplemental boron.
Asunto(s)
Densidad Ósea/efectos de los fármacos , Boro/farmacología , Oviposición/efectos de los fármacos , Alimentación Animal , Animales , Peso Corporal/efectos de los fármacos , Boro/administración & dosificación , Boro/farmacocinética , Pollos , Conducta Alimentaria/efectos de los fármacos , Femenino , Alimentos Fortificados , Radio (Anatomía)/efectos de los fármacos , Radio (Anatomía)/fisiología , Fracturas del Radio/fisiopatología , Fracturas del Radio/prevención & control , Estrés Mecánico , Tibia/efectos de los fármacos , Tibia/fisiología , Fracturas de la Tibia/fisiopatología , Fracturas de la Tibia/prevención & control , Distribución TisularRESUMEN
There have been many methods proposed to induce molting. Some worked very well in practice, but others were detrimental to the health and welfare of the hens. The most effective methods use some level of feed restriction and daylength manipulation to reduce body weight (Hansen, 1966; Ruszler, 1974, 1984, 1996; Swanson and Bell, 1974; Brake and Carey, 1983). Weight reduction is necessary for rest and rejuvenation of body tissues. Other methods evaluated incorporated dietary imbalances using either zinc, iodine, or sodium. Pharmaceuticals have been used but have not been cost effective. In recent years there have been those who question whether molting techniques are humane. Therefore, interest has been heightened in alternate methods to induce molting. Research reported to date has been inadequate to accurately determine which methods of induced molting are the least stressful, if they in fact, cause any more stress than that experienced by the hen during a natural molt. The three or four most highly refined methods being used commercially are not generally detrimental to the health and welfare of today's laying hen, provided that they are managed in accordance with proper husbandry practices.
Asunto(s)
Crianza de Animales Domésticos , Bienestar del Animal , Muda/fisiología , Aves de Corral/fisiología , Animales , Femenino , Privación de Alimentos , Oviposición , Fotoperiodo , Pérdida de PesoRESUMEN
The effect of dietary boron on bone ash content and on the ultimate shear force, stress, and fracture energy of the tibia, femur, humerus, and radius from white Leghorn pullets were investigated. There was a significant increase in the shear force of the tibia and femur for pullets supplemented with 50 and 100 mg/kg of dietary boron. There was a significant increase in the shear stress of the tibia at 50 and 100 mg/kg of boron, and also an increase in shear fracture energy at 50 and 100 mg/kg boron for the femur. Tibia bone ash content increased significantly at 50, 100, and 200 mg/kg boron with the highest value at 50 mg/kg. Even though there was not a significant increase in body wt at 50 and 100 mg/kg boron, the pullets fed these supplements were consistently heavier than the control group.
Asunto(s)
Huesos/efectos de los fármacos , Boro/administración & dosificación , Boro/metabolismo , Pollos/crecimiento & desarrollo , Animales , Peso Corporal/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Huesos/química , Huesos/metabolismo , Boro/química , Alimentos Fortificados , Fracturas Óseas/metabolismo , Fracturas Óseas/fisiopatología , Hígado/crecimiento & desarrollo , Hígado/metabolismo , Glándulas Mamarias Animales/crecimiento & desarrollo , Glándulas Mamarias Animales/metabolismo , Minerales/metabolismo , Estrés MecánicoRESUMEN
1. The effects of dietary boron on egg production and on the ultimate shear force, stress, and fracture energy of the tibia, femur, humerus, and radius from White Leghorn laying hens were investigated. 2. The shear force, stress, and fracture energy of the bones were not affected by increasing dietary concentrations of boron. 3. Egg production, food consumption and body weight were suppressed at a dietary boron concentration of 400 mg/kg. 4. Boron concentrations increased significantly in all tissue samples tested in birds given 400 mg/kg dietary boron.
Asunto(s)
Boro/farmacología , Pollos/fisiología , Dieta/veterinaria , Oviposición/efectos de los fármacos , Análisis de Varianza , Animales , Peso Corporal/fisiología , Densidad Ósea/efectos de los fármacos , Densidad Ósea/fisiología , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/fisiología , Femenino , Fémur/fisiología , Alimentos Fortificados , Húmero/fisiología , Oviposición/fisiología , Radio (Anatomía)/fisiología , Tibia/fisiologíaRESUMEN
A simple quantitative method (moving sticky tape) to monitor house fly populations in commercial caged layer houses was described and compared with a standard monitoring (spot card) method routinely used in egg houses. Numbers of flies counted by the sticky tape method were highly correlated (.78, P = .005) with those obtained with the spot card method. The moving sticky tape method is quicker and easier to use than the spot card method. The moving sticky tape method has been used satisfactorily since 1985 by the authors and cooperating service managers of commercial caged layer houses to monitor house flies in integrated pest management programs. A fixed sticky tape method was also compared with the spot card method; there was no significant correlation between the numbers of flies counted by these two methods.
Asunto(s)
Pollos , Dípteros , Vivienda para Animales , Animales , Femenino , Control de Insectos/métodosRESUMEN
Effects of sequential changes in dietary protein on growth from 0 to 20 weeks of age and on egg production from 20 to 72 weeks of age were evaluated with White Leghorn chickens. Four dietary treatments were compared. They consisted of three dietary regimens wherein an 18% crude protein (CP) diet was fed to 1, 2, or 3 weeks of age (Treatments 1, 2, and 3, respectively) and then common 12, 15, and 18% CP diets to 8, 14, and 20 weeks, respectively. These three regimens were compared with a control regimen (Treatment 4) that consisted of feeding 18, 15, and 12% CP diets to 6, 14, and 20 weeks of age, respectively. At 20 weeks of age, 144 birds from each treatment were moved into laying cages for the subsequent 52 weeks of egg production. In comparison with birds on the control feeding regimen, those reared under Treatments 1, 2, and 3 consumed significantly less feed during the 20-week growing period. Birds of Treatments 2 and 3 consumed significantly more protein than those of Treatments 1 and 4. By feeding a 12% CP diet from 1, 2, and 3 to 8 weeks of age, body weights were significantly lower than the average body weight of the control birds, approximately 20, 17, and 13%, respectively, by 6 weeks of age, but only 2 to 4% at 16 weeks of age, and by nonsignificant amounts at 28 weeks of age. Treatment 1 birds consumed 1.8% (significantly) less feed per unit body weight and were 2.6% (significantly) lighter at 20 weeks of age compared with the control birds.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Pollos/fisiología , Proteínas en la Dieta/administración & dosificación , Oviposición , Análisis de Varianza , Animales , Peso Corporal , Pollos/crecimiento & desarrollo , FemeninoRESUMEN
The purpose of this study was to investigate the effects of claw removal on young pullets grown in wire cages. Body weight, feed consumption, stress response, and gonadal steroid date were collected to assess the effects of claw removal and growing pullets. Claw removal posed an initial physiological insult upon chicks that resulted in a reduction in body weight gain and reduced feed consumption during the early grow-out period. However, by 20 weeks of age there were no significant differences between the body weights of intact and declawed pullets. No significant differences in plasma corticosterone, progesterone, or estradiol were observed, nor were there any significant differences in mortality or antibody response during the course of the 20-week study. Nevertheless, several declawed pullets demonstrated relatively precocious egg laying, suggesting that claw removal enhanced sexual maturity.