Effect of organic mineral supplementation on the egg quality of semi-heavy layers in their second cycle of lay

This study was carried out to evaluate the effects of dietary trace mineral levels and sources on egg quality parameters of second-cycle semi-heavy layers. A number of 360 72-week-old layers were submitted to forced molting. Upon return of lay (83 weeks of age), birds were distributed according to a completely randomized experimental design of six treatments with six replicates of 10 birds each. The control treatment consisted of 0.10% dietary supplementation of trace minerals from inorganic sources, which was proportionally replaced by five levels (110, 100, 90, 80, 70%) of an organic trace mineral supplement containing 30, 30, 40, 6, 0.61, and 0.3 g/kg product of Zn, Fe, Mn, Cu, I, and Se, respectively. All diets contained equal protein, energy, and amino acid levels. Every 28 days of the experimental period (112 days) four eggs per replicate were collected for egg quality evaluation. The following parameters were evaluated: specific gravity, yolk, albumen and eggshell percentages, yolk index, Haugh units, and eggshell thickness and breaking strength. One sample per replicate, consisting of the pool of the yolks of three eggs collected at the end of each experimental period, was used to assess protein and mineral (Ca, P, Cu, Fe, Mn, and Zn) contents. The results were submitted to ANOVA, and means to the test of Tukey at 5% significance level. The evaluated trace mineral levels and sources did not influence any of the studied egg quality parameters. It was concluded that reducing organic trace mineral supplementation in up to 70% relative to 100% inorganic trace mineral supplementation does not affect egg parameters and therefore, can be applied to the diet of semi-heavy layers in their second cycle of lay.

Production performance and egg quality of quails (Coturnix japonica) during several periods of the day

Three experiments were carried out to analyze the performance and egg quality of Japanese quails throughout the day when submitted to different lighting programs. In each experiment, birds were submitted to a period of 28 days for adaptation to the lighting program. During the following three days, each day - from 7 am to 7 pm or 9 pm - was divided into six or seven periods of two hours each, and the remaining hours corresponded to another single period. All birds were submitted to the same management practices, and received water and feed ad libitum. The experimental diet was formulated according to NRC (1994) standards. It was observed lower feed intake in the period of 9 pm to 7 am, and a higher incidence of lay from 3 pm to 7 pm, as opposite to hens, which peak of egg laying occurs during the morning. Some controversial results were found among experiments as to eggshell quality during the different periods of the day. Variation on the lighting program had little influence on the other performance and egg quality parameters.

Effect of the calcium level and limestone particle size on the performance of semi-heavy layers in the second cycle of egg production

An experiment was carried out at the Research and Development Unit of Brotas aiming at evaluating dietary calcium level and limestone particle size on the production performance of commercial (Hy-Line Brown) layers in the second lay cycle. Experiment duration was 112 days. A total number of 288 hens, with 83 weeks of age in the beginning of the experiment, were used in a completely randomized experimental design in a factorial arrangement of 2x3, with two calcium levels (3.5 and 4.0%) and three limestone particle size compositions: 100% fine limestone (FL), 30% coarse limestone (CL) + 70% fine limestone (FL), and 50% (CL) + 50% (FL), with six replicates of eight birds each. Egg weight (g), egg production (%), egg mass (%), feed intake (g), feed conversion ratio (kg/dz and kg/kg), mortality (%), and egg loss (%) were evaluated. The analysis of variance did not detect significant differences (p>0.05) among treatments on any of the evaluated performance parameters. It was concluded that the tested calcium levels and limestone particle composition did not influence the performance of semi-heavy layers in second production cycle.

Forced-Molting methods and their effects on the performance and egg quality of japanese quails (Coturnix japonica) in the second laying cycle

The experiment was carried out in the experimental poultry house of the Research and Development Unit of Brotas of Agência Paulista de Tecnologia dos Agronegócios do Centro-Oeste, SP, Brazil. The objective of the study was to evaluate the performance of Japanese quails submitted to forced molting aiming at optimizing the use of the same quail flock by promoting a second laying cycle. A total number of 400 67-day-old Japanese quails in lay, previously submitted to 14 days of forced molting, was distributed in a completely randomized experimental design into five treatments (T1= not submitted to forced molting, T2= 03 days of fasting + fed ad libitum, T3= 01 days of fasting + 13 days of feed restriction, T4= 02 days of fasting + 12 days of feed restriction, and T5= 03 days of fasting + 11 days of feed restriction. Feeds were contained equal nutrient levels, and were formulated according to NRC (1994) recommendations. There were significant differences among the studied treatments. Although the treatment of 3 days of fasting followed by ad libitum feeding resulted in lower egg weight, it promoted better lay percentage, egg mass, and feed conversion ratios (FCR/dz and FCR/kg). on the other hand, 3 days of fasting followed by restricted feeding resulted in higher feed intake and worse feed conversion ratios (FCR/dz and FCR/kg). When birds were not submitted to forced molting, they presented lower lay percentage and egg mass.

Ground annatto seeds (Bixa orellana L.) in sorghum-based commercial layer diets and their effects on performance, egg quality, and yolk pigmentation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Replacing egg yolk with soybean lecithin in the cryopreservation of stallion semen

The objective of this study was to determine whether replacing the egg yolk with soybean lecithin in the Botu-Crio (R) cryodiluent would maintain the fertility of cryopreserved stallion sperm. Two experiments were performed to evaluate cell freezability. In experiment 1, sperm from 15 stallions were frozen in Botu-Crio (R) (BC) or Botu-Crio (R) which contained 45 g/L soybean lecithin (BCLS45) in place of the egg yolk. In experiment 2, we compared different concentrations of soybean lecithin: 0, 10.0, 12.5, 15.0, 17.5 and 20.0 g/L (BC, BCLS10, BCLS12.5, BCLS17.5 and BCLS20, respectively). In experiment 1, sperm frozen in BC and BCLS45 exhibited similar (P > 0.05) percentages of total motile sperm (61% and 61%, respectively); progressively motile sperm (27% and 27%, respectively) and sperm with intact plasma membranes (IMP; 53% and 57%, respectively). Similarly, sperm frozen in BC or BC containing any concentration of soybean lecithin maintained similar (P > 0.05) percentages of total motile sperm (61-68%) and progressively motile sperm (27-31%). In the first fertility trial, we used cryopreserved semen from a single stallion was inseminated into mares. The semen from the sperm that were frozen in BC diluent resulted in a higher fertility rate (66%, 16/24) compared to the sperm that were frozen in BCLS45 diluent (17%, 5/29; P < 0.01). Similarly, in a second fertility trial, the mares that were inseminated with the sperm that were frozen in BC diluent exhibited a higher fertility rate (66%, 16/24) compared to the mares that were inseminated with the sperm that were frozen in BCLS20 (40%, 10/25; Pc 0.05). Finally, in a third trial, the sperm that were frozen in BC resulted in a higher fertility rate in mares (75%, 18/24) compared to the sperm that were frozen in BCLS10 (41%, 10/24; P < 0.05). Although replacing the egg yolk in the BC cryodiluent with soybean lecithin provided similar laboratory results for stallion sperm, after cryopreservation, the sperm that was frozen with soybean lecithin in the diluent correlated with lower fertility rates. Based on these results, we concluded that the use of BCLS can be used as an alternative diluent for cryopreserving stallion sperm. However, the resulting reduced fertility rate is a matter of concern. Further studies are necessary to clarify the reasons for this decrease in fertility and to determine the optimal lecithin concentration for diluents to freeze stallion sperm. (C) 2011 Elsevier B.V. All rights reserved.

The effects of alternative forced-molting methods on the performance and egg quality of commercial layers

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Comparison of in vitro and in vivo fertilizing potential of bovine semen frozen in egg yolk or new lecithin based extenders

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Motility and viability of ram sperm cryopreserved in a Tris-egg yolk extender supplemented with anti-oxidants

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fecal specimens preparation methods for PCR diagnosis of human taeniosis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Molecular identification of Cryptosporidium spp. from fecal samples of felines, canines and bovines in the state of São Paulo, Brazil

The objective of this study was to obtain information of epidemiological nature through genotypic characterization of Cryptosporidium isolates from dogs, cats and bovines from the state of São Paulo, Brazil. The extraction of DNA from oocysts was carried out and polymerase chain reaction was accomplished using specific primers to 18S rRNA gene. The amplicons were directed sequenced. Seven cat samples, nine dog samples and nine bovine samples were analysed. From the seven cat samples the genotypic analyses revealed Cryptosporidium felis in all. These were the first genotypic characterization of Cryptosporidium from domestic felines in Brazil. In nine sequenced samples from dogs, genotypic identities compatible with Cryptosporidium canis were revealed in all samples. The genotypic analyses in bovines revealed Cryptosporidium parvum in eight samples and Cryptosporidium bovis in another sample, the last one being a non-zoonotic species, not related to clinical symptoms and described for the first time in Brazil. (c) 2007 Elsevier B.V. All rights reserved.