Number Of Cracked Eggs Research Articles

Transporte de ovos férteis: Influência das idades das matrizes, tempos de estocagem e das estradas

Propôs-se, com esta pesquisa, avaliar a influência de diferentes idades das matrizes e tempos de estocagem no número de ovos trincados durante a operação de transporte em diferentes estradas. A pesquisa foi conduzida na empresa integradora avícola em Mogi-Mirim - SP, por meio do acompanhamento de três carregamentos em diferentes estações do ano (primavera, verão e outono). Foi utilizado um caminhão climatizado do tipo baú com capacidade para 592 caixas de ovos. Foram registrados, por meio de quatro acelerômetros, os níveis de vibração (m s-2) e choques em percursos realizados nas estradas de terra e asfalto. O número de ovos trincados foi obtido por meio da contabilização de 18 caixas de ovos transportadas que apresentavam três idades de matrizes e três tempos de estocagem, pelo método visual. Foi utilizado o delineamento experimental inteiramente aleatorizado com esquema fatorial 3 x 3. Conclui-se que as matrizes velhas e intermediárias apresentaram o maior número de ovos trincados; os maiores níveis de vibração e choques da carga ocorreram no sentido horizontal enquanto a estrada de asfalto ofereceu as piores condições para o transporte de ovos.

Effects of Different Sources of Microbial Phytase on Production Performance of Brown-Egg Layers Fed Diets Containing a High Level of Rice Bran

Rice bran is widely used in rice-producing countries as a feed ingredient in layer diets. It contains a high level of P, of which 80% is phytate-bound P. A trial was conducted on a commercial layer farm to evaluate effects of three different sources of microbial phytase (Phytase A, Phytase B, and Phytase C) on production performance of brown-egg layers fed diets containing 22% rice bran. A total of 46,080, 23-wk-old layers was used. They were randomly allocated to 20 identical houses containing 2,304 birds per house. A standard control diet containing 0.31% nonphytate P and 3.60% calcium was used. The control diet was reformulated to contain 0.19% nonphytate P to which three different sources of microbial phytase were added. Phytase A was added at 180 g/ tonne, Phytase B at 120 g/tonne, and Phytase C at 60 g/tonne. All experimental diets were fed to layers for 25 wk. Results indicated that there were no statistically significant phytase effects, regardless of source, on hen-day production, feed intake, egg mass, or number of cracked eggs when compared to the control treatment group. The result suggests that Phytases A, B, and C are effective sources of microbial phytase that can be used in reduced-P layer diets containing a high level of rice bran.

Effects of Dietary Yucca schidigera Powder on Performance and Egg Cholesterol Content of Laying Hens

Kutlu, H.R., Görgülü, M. and Ünsal, I. 2001 Effects of dietary Yucca schidigera powder on performance and egg cholesterol content of laying hens. J. Appl. Anim. Res., 20: 49–56. The present study was carried out to determine whether dietary Yucca schidigera powder would affect egg yolk cholesterol content and laying performance of chickens. Sixty, 28-week-old White Hyline layers were divided into four dietary treatment groups of similar mean weight, comprising 15 birds each. A standard layer feed as the basal diet of the trial was supplemented with 0, 30, 60 or l20 ppm Yucca schidigera powder. Yucca supplementation to the diet did not affect feed intake, egg production, feed conversion efficiency, body weight gain, egg shell, white and yolk weights, shell thickness and shape index but reduced number of cracked eggs (P<0.05). Yucca supplementation also reduced yolk cholesterol content in a dose related (P<0.05) and a time dependent (P<0.01) manner.

Factors affecting the use of perches in cages by laying hens

1. Three experiments were carried out with ISA Brown laying hens housed in individual cages with softwood perches of rectangular cross section fitted across the width of each cage, to investigate factors affecting the tendency of hens to lay their eggs from the perches and to use perches at other times. These factors were perch width and angle and method of perch introduction. 2. In experiment 1 there were 4 treatments. Perches were 38 or 60 mm wide; half of each width were flat and half were fixed at 8 , parallel to the slope of the floor. In 2 similar trials (with 48 and 44 birds respectively, equally divided between treatments) birds were moved to experimental cages already fitted with perches. Birds with 38 mm, sloping perches laid less than one third of their eggs from the perch (31% and 9% in the two trials) while those with the other designs laid more than 80% from the perch. Narrow sloping perches were not otherwise aversive and there was no consistent variation between treatments in total time perching. 3. In experiment 2, 32 birds were allowed to start laying on the floor of the experimental cages then perches were introduced at 24 weeks with 8 birds on each of 4 treatments: 50 mm perches fixed flat and 38 mm perches fixed flat, and at 5 and 10 respectively. Only 27% of eggs were laid from the perches with no variation between treatments either in this behaviour or in total time perching. 4. Experiment 3 provided 24 of the birds from experiment 2 with double-length perches to determine whether they showed preferences for the design features under consideration. Either half the perch length was flat and half sloping at 10 or half was 38 and half 50 mm wide. Again a relatively low proportion of eggs was laid from the perches (18%) and birds showed no significant preference for different perch designs as indicated by either how much they perched or where they perched. 5. These results suggest that both perch design and the way pullets are introduced to perches influence the proportion of perch-laid eggs. They confirm that in some circumstances laying from perches can be a serious problem, but that in other circumstances incidence can be reduced to a manageable frequency. Perches may therefore be practical in commercial production without increasing the number of cracked eggs. The results are also likely to be applicable in cages with other facilities including nest boxes.

The Effect of Different Levels of Vitamin C and Cholecalciferol with Adequate or Marginal Levels of Dietary Calcium on Performance and Eggshell Quality of Laying Hens

Three experiments were conducted to determine whether shell quality, bone mineralization, and other production traits could be improved by adding vitamin C (ascorbic acid) to laying hen diets. The period of each experiment was 12 wk. Experiment 1 consisted of a 2 × 2 × 3 factorial design with two levels of Ca (2.8 and 3.8%), two levels of cholecalciferol (vitamin D3; 2,200 and 4,400 IU/kg diet), and three levels of vitamin C (0, 125, and 250 ppm). Experiment 2 consisted of a 2 × 3 × 2 factorial design with two levels of Ca (2.8 and 3.8%), three levels of vitamin D3 (250, 500, and 2,000 IU/kg diet), and two levels of vitamin C (0 and 250 ppm). Experiment 3 consisted of a 2 × 4 factorial design with two sources of vitamin D3 (12.5 μg vitamin D3/kg diet or 12.5 μg 25-OH-D3/kg diet) and four levels of vitamin C (0, 250, 500, and 1,000 ppm). Calcium level was kept constant at 3.5% for all the diets in Experiment 3.Production performance was not influenced by dietary treatments in Experiment 1. In Experiment 2, feed conversion was improved (P < 0.05) due to increasing the dietary Ca, and egg weight and egg size were increased (P < 0.05) due to adding 250 ppm vitamin C to the diet. In Experiment 3, albumen quality was increased by the addition of 1,000 ppm vitamin C to the diet. Egg specific gravity was increased in Experiments 1 and 2 only, due to increasing the Ca level (P < 0.05). In Experiment 2, increasing the Ca level and increasing the vitamin D3 level from 250 to 2,000 ppm reduced (P < 0.05) the number of cracked eggs, but incidence of cracked eggs was increased with the addition of 250 ppm vitamin C to the diet. In Experiment 1, plasma level of l,25(OH)2D3 was greater (P < 0.05) for hens fed 2.8 than 3.8% Ca, but blood acid-base balance was not influenced by dietary regimens. Bone ash was not influenced by dietary treatments in any of the experiments. The data indicated that a supplemental level of vitamin C had no beneficial effects on shell quality and bone mineralization under the conditions of the current experiments.