Obtaining Microbiologically Safe Hatching Eggs from Hatcheries: Using Essential Oils for Integrated Sanitization Strategies in Hatching Eggs, Poultry Houses and Poultry.

Essential oils are liquids containing non-toxic compounds that are unfavorable to the growth of microorganisms. They are sold globally at affordable or very high prices, depending on the availability and type of plant, the scale of production, the extraction method, costs associated with logistics and electricity consumption, among other variables. Each year, the quantity of research dedicated to the antimicrobial potential of essential oils in poultry farming is expanding. Researchers consensually relay that this increase is due to the growing resistance of microorganisms to traditional antimicrobials and concerns about the toxicity of these products. This review proposes an analysis of the antimicrobial feasibility of using essential oils to address microbial challenges in poultry farms, aiming to ensure the production and supply of microbiologically safe hatching eggs. Based on the findings in the literature, in addition to following other necessary precautions in the daily routines of poultry farming practices, developing an antimicrobial control program with essential oils that integrates poultry facilities, poultry and hatching eggs, adapted to the particularities of each context seems to be extremely effective.

Control of Escherichia coli in Poultry Using the In Ovo Injection Technique.

Pathogens, such as Escherichia coli (E. coli), have been identified as significant causes of poultry mortality. Poultry can serve as potential sources of E. coli transmission, even when asymptomatic, posing a substantial threat to food safety and human health. The in ovo administration of antimicrobials is crucial for preventing and/or effectively combating acute and chronic infections caused by poultry pathogens. To achieve this goal, it is critical that antimicrobials are properly injected into embryonic fluids, such as the amnion, to reach target tissues and trigger robust antimicrobial responses. Several protocols based on antimicrobials were evaluated to meet these requirements. This review analyzed the impacts of antimicrobial substances injected in ovo on the control of E. coli in poultry. The reduction in infection rates, resulting from the implementation of in ovo antimicrobials, combined with efforts aimed at hygienic-sanitary action plans in poultry sheds, reinforces confidence that E. coli can be contained before causing large scale damage. For example, antimicrobial peptides and probiotics have shown potential to provide protection to poultry against infections caused by E. coli. Issues related to the toxicity and bacterial resistance of many synthetic chemical compounds represent challenges that need to be overcome before the commercial application of in ovo injection protocols focused on microbiological control.

A Mini-Review of the Main Effects of Essential Oils from Citrus aurantifolia, Ocimum basilicum, and Allium sativum as Safe Antimicrobial Activity in Poultry.

Poultry production is accompanied by the use of antimicrobial agents because no production step is free of microorganisms. In the absence of antimicrobial treatments with synthetic drugs, essential oils are among the most cited natural alternatives used to prevent and treat microbial contamination in poultry. Although there are several studies on the antimicrobial properties of essential oils, there is still no review that simultaneously compiles information on the leading antimicrobial role of essential oils from Citrus aurantifolia (CAEO), Ocimum basilicum (OBEO), and Allium sativum (ASEO) in poultry. Awareness of the antimicrobial role of these substances opens the door to encouraging their use in natural antimicrobial protocols and discouraging harmful synthetics in poultry. This review aimed to compile information on applying CAEO, OBEO, and ASEO as antimicrobials in poultry farming. The available literature suggests that these essential oils can proportionately align with the poultry industry's demands for microbiologically safe food products.

Antimicrobial Coating Based on Tahiti Lemon Essential Oil and Green Banana Flour to Preserve the Internal Quality of Quail Eggs.

This study evaluated the microbiological and internal quality of quail eggs stored for 21 days at room temperature (29.53 ± 1.36 °C) after being coated with green banana flour and Tahiti lemon essential oil (GBF/TAH). One hundred and sixty-two quail eggs were equally distributed into three treatments: (1) uncoated eggs, (2) eggs coated with green banana flour (GBF), and (3) eggs coated with GBF/TAH. The Haugh unit (HU) of the eggs was significantly lower in the third week for uncoated eggs (70.94 ± 1.63, grade A) compared to eggs coated with GBF/TAH (81.47 ± 2.38, grade AA). On the 21st day of storage, the eggs coated with GBF/TAH had significantly lower total counts of aerobic mesophilic bacteria in the shell and egg contents compared to the other treatments. GBF/TAH coating is an effective blending approach to reduce the microbial load of the shell and egg contents and preserve the sensory and internal quality of the eggs.

Bibliographical Mapping of Research into the Relationship between In Ovo Injection Practice and Hatchability in Poultry.

Recent advances in poultry practice have produced new tools enabling the poultry industry to increase productivity. Aiming at increasing production quality, varying protocols of in ovo injection facilitate the introduction of exogenous substances into the egg to complement the nutrients that support embryonic development up to hatching, which are already available in the internal and external compartments. Due to embryonic sensitivity, adding any substance into the egg can be either advantageous or disadvantageous for embryonic survival and can influence hatch rates. Thus, understanding the relationship between poultry practices and production rates is the first step towards successful commercial application. This review aims to assess the influence on hatch rates of injecting different substances in ovo, including effects on embryo and chick health parameters where these are reported. Bibliographic mappings of co-authorship of citations, co-occurrence of keywords, and bibliographic coupling based on the in ovo injection technique and hatchability parameters were also performed. Using the Scopus database, 242 papers were retrieved, reviewed, and submitted for bibliographic mapping using the VOSviewer® software. This review provides a broad overview of just over 38 years' research on the subject, revealing that studies have significantly increased and peaked in 2020, being produced primarily by US researchers and published primarily in the journal Poultry Science. It also reveals that despite negative reports relating to some substances in the embryo, in ovo delivery of substances may possibly change the poultry industry for the better in terms of production rates (hatchability) and/or poultry health.

Effects of Sanitizers on Microbiological Control of Hatching Eggshells and Poultry Health during Embryogenesis and Early Stages after Hatching in the Last Decade.

The sanitization of hatching eggs is the backbone of the hygienic-sanitary management of eggs on farms and extends to the hatchery. Poultry production gains depend on the benefits of sanitizers. Obtaining the maximum yield from incubation free of toxic sanitizers is a trend in poultry farming, closely following the concerns imposed through scientific research. The toxic characteristics of formaldehyde, the primary sanitizer for hatching eggs, are disappointing, but it is a cheap, practical and widely used antimicrobial. To overcome this shortcoming, multiple synthetic and natural chemical sanitizers have been, and continue to be, tested on hatching eggs. This review aims to evaluate the effects of different sanitizers on the microbiological quality of hatching eggshells and poultry health during embryogenesis and early stages after hatching.

The potential of natural shade provided by Brazilian savanna trees for thermal comfort and carbon sink.

This study looked at the potential of thermal comfort provided to animals by four different Brazilian savanna (Cerrado) native trees, as well as their potential for carbon sink. The evaluations were carried out during the summer of 2020, which consisted of the collection of microclimate variables. The Mean Radiant Temperature (TMR, °C) was derived from the shaded and unshaded areas under the trees, and from that, the Radiant Heat Load (RHL, W m-2) was calculated as an index of thermal comfort. Solar radiation was estimated considering the sum of the direct, diffuse, and reflected components (W m-2), and carbon stock from trees biomass for CO2 sequestration was estimated from an allometric model applied to the native Cerrado tree species. The shade of the native trees reduced the meteorological variables such as dry bulb and black globe temperatures, to values considered adequate for the thermal comfort of animals, with an average reduction respectively equal to 1.3 °C and 6.4 °C. This represents a significant difference compared to the unshaded area as well as among tree species (P < 0.05), reflecting in lower values of TMR and RHL in the shaded area provided by each species. Carbon sequestration individually estimated by each native tree species was on average 8.85 Mg per tree. These results demonstrate the great potential for native tree species in the Cerrado biome to be used in agroforestry systems to provide higher levels of thermal comfort to animals and to combat climate change through their aptitude of CO2 sink.

Solar radiation limits the use of paddocks by laying hens raised in the free-range system.

Laying hens on the free-range systems are susceptible to challenging situations in relation to the rearing environment. Therefore, this work evaluated how solar radiation influences the behavior of laying hens raised in a free-range system, in the Brazilian Savanna. The activities included data collection of meteorological variables and behavioral analysis of 300 commercial laying hens in relation to the frequency of use of indoor and outdoor areas of rearing housing. The solar radiation is the main factor that directly affects the heat gain of production animals, in this experiment had a high amplitude during all day, going from 33.42 to 756.98 W m-2. It was observed that the highest frequency of 79% and 91% use of the barn areas by the hens was at 8 am and 4 pm, respectively. The internal area of the housing was more used by hens 87% and 68% at 12 h and 14 h, respectively. Hens were not observed in the paddocks at noon and 2 pm. Hens spend more than 6 h of the day inside the housing to provide shelter from solar radiation. Which the conclusion the solar radiation influences the behavior of laying hens, at times of the day of the higher incidence of radiation, and high air and global temperatures, it was not observed the presence of hens in the external areas of the housing, especially with the use of the paddocks; at these times the hens seek shelter inside the housing to get away from the incidence of direct solar radiation.

Thermal comfort provided by different shading structures in free-range systems in Brazilian savanna.

This work aimed to evaluate the thermal comfort provided by shading structures in free-range systems under a tropical environment, based on microclimate variables of nets with different materials. During the experiment, the unshading area; the natural shading of a native tree species to the Brazilian Savanna; and the artificial 80% shadings nets: black polypropylene, heat-reflective aluminized, and association of both were evaluated. The shading structures were analyzed in paddocks at the Água Limpa Farm from the University of Brasília, where dry-bulb, wet-bulb, black globe temperatures, and wind speed were collected for the micrometeorological characterization from 8:00 am to 4:00 pm. From the temperatures, the vapor pressures and the humidities were calculated. The shortwave radiation was calculated through the sum of direct, diffuse, and reflected radiations. The mean radiant temperature, radiant heat load, and black globe temperature and humidity index were calculated. The internal and external surface temperatures of the nets and the soil temperature were measured every 30 min. The data were analyzed with aid of the statistical analysis system. The air temperature varied according to the shortwave radiation, from 25.6 °C at 8:00 am to 29.6 °C at 1:00 pm, with a decrease over the hours. Despite the air temperature of the trees showed the lowest average, the nets association structure was the most reduced all the thermal comfort indexes. The heat-reflective net presented the lowest soil temperature at all hours (under 26.1 °C). In general, the shadings proved to be efficient in promoting thermal comfort in free-range systems.

Spraying Hatching Eggs with Clove Essential Oil Does Not Compromise the Quality of Embryos and One-Day-Old Chicks or Broiler Performance.

The objective of this study was to evaluate whether sanitizing hatching eggs with clove essential oil in the preincubation phase affects broiler performance and influences the hatch window and quality of embryos and one-day-old chicks. Hatching eggs (n = 1280; mean weight = 58.64 ± 0.49 g) from a batch of 37-week-old broiler breeder hens of the CPK (Pesadão Vermelho) lineage were randomly distributed into four treatments in the preincubation phase. The treatments consisted of three different sanitization procedures (spraying with grain alcohol, spraying with clove essential oil, and fumigation with paraformaldehyde) and a control treatment (nonsanitized). The lengths of the embryos and one-day-old chicks (one of the parameters used to assess bird quality) were not significantly different among the treatments, with means of 15.30 ± 1.41 and 18.37 ± 0.76 mm, respectively. Body weight, body weight gain, feed consumption, and feed conversion rate in different rearing periods did not differ significantly among the treatments. However, there was a significant difference in the percentage of survivability during the initial period (1 to 28 days) among the treatments. In conclusion, clove essential oil treatment did not negatively affect the quality of embryos and one-day-old chicks or the performance of broilers.

Thermal comfort of sows in free-range system in Brazilian Savanna.

The aim of this work was to evaluate the thermal comfort of sows in a free-range system in the Brazilian Savanna, based on behavior observation, availability of shading resources, meteorological and physiological variables. The sows were analyzed in the gestation sector at Água Limpa Farm from University of Brasília; the sows were housed in paddocks of 1000 m2 each containing artificial and natural shading structures, where air temperature (Tair, °C), wind speed, relative humidity (RH, %) and black globe temperatures (TG, °C) were collected for the environment characterization in 20-min-intervals. From the black globe temperature, the Mean Radiant Temperature (TMR, °C) and the Radiant Heat Load (RHL, W m-2) were calculated in the sun and under the shade structures. The total short-wave irradiance was calculated through the sum of direct, diffuse and reflected radiations. For the behavioral evaluation, an ethogram was elaborated, taking in consideration where the animals were in the paddocks, body posture, and the activity performed. The physiological variables such as respiratory rate (breaths.min-1), surface and rectal temperatures (°C) were measured during the experiment. The data was statistically analyzed through analysis of variance and frequency analysis. There was a difference at 11a.m., 2 and 3p.m., with values above 40 °C under the shade and above 70 °C in the sun for the TMR. The preferential choice was for natural shading by the sows, due to the lower TMR and RHL throughout the day and resting activity had been predominated. The rectal temperature did not differ between the animals and the days evaluated, respiratory rate varied according to air temperature, and surface temperature only among the evaluated animals. It was concluded that even when there is a greater radiation incidence and meteorological variables above the condition of comfort for sows, they did not express any abnormal behavior that could indicate discomfort.