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1.
Poult Sci ; 100(9): 101375, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34358953

RESUMO

The amount and timing of growth are important factors that affect age at first egg, body conformation, reproductive performance, and hunger in broiler breeders. To investigate the effect of growth pattern on feeding motivation and reproductive performance, 10 unique growth trajectories were designed with 2 levels of the amount of early growth and 5 levels of timing of growth around puberty. A 3-phase Gompertz model that described growth in phase 1 (prepubertal), phase 2 (pubertal), and phase 3 (postpubertal) was used to design the growth trajectories. Second growth phase inflection point (I2) was advanced by 0, 5, 10, 15, or 20% of the coefficient estimated from the breeder-recommended target BW. The growth trajectories were designed with 2 discrete levels of total gain in the prepubertal phase (g1); g1 was either the prepubertal phase gain coefficient, estimated from the breeder-recommended BW (Standard g1) target, or 10% higher (High g1). Forty females were randomly assigned to the growth trajectories using a precision feeding (PF) system. Analysis of covariance was conducted on dependent variables in ten 4-wk periods with g1 and periods as discrete fixed effects, I2 as a continuous fixed effect, and age as a random effect. Differences were reported at P ≤ 0.05. For every week of earlier I2, body weight at photostimulation (BWPS) increased by 126 g; BW at first egg (BWFE) increased by 94 g; 24 wk shank length increased by 0.038 and 1.495 mm in the Standard g1 and High g1 treatments; 24 wk body fat increased by 0.38%; pullets came to lay earlier by 0.49 d; egg weight (EW) increased by 0.27 g; egg production and egg mass (EM) increased by 0.33 egg/hen/d and 0.916 g/d in the High g1 treatment but decreased by 0.27 egg/hen/d and 0.29 g/d in the Standard g1 treatment, respectively. Increasing g1 reduced feeding motivation index by 1.6 and 0.8 visits/meal during rearing and laying phase, respectively. Earlier pubertal growth showed prominent effects on the reproductive performance.


Assuntos
Galinhas , Motivação , Ração Animal/análise , Animais , Peso Corporal , Dieta , Feminino , Fenótipo , Reprodução , Maturidade Sexual
2.
Poult Sci ; 100(8): 101187, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34198100

RESUMO

Identifying daily oviposition events for individual broiler breeders is important for bird management. Identifying non-laying birds in a flock that might be caused by improper nutrition or diseases can guide diet changes or disease treatments for these individuals. Oviposition depends on follicle maturation and egg formation, and follicle maturation can be variable. As such, the day and time of oviposition events of individual birds in a free-run flock can be hard to predict. Based on a precision feeding (PF) system that can record the feeding activity of individual birds, a recent study reported a machine learning model to predict daily egg-laying events of broiler breeders. However, there were 2 limitations in that study: 1) It could only be used to identify daily egg-laying events on a subsequent day; 2) The prediction outputs that were binary labels were unable to indicate more details among the outputs with the same label. To improve the previous approach, the current study aimed to predict and output the probability of daily oviposition events occurring using a specific time point in 1 day. In the current study, 706 egg-laying events recorded by nest boxes with radio frequency identification of hens and 706 randomly selected no-egg-laying events were used. The anchor point was newly defined in the current study as a specific time point in 1 day, and 26 features around the anchor point were created for all events (706 egg-laying events and 706 no-egg-laying events). A feed-forward artificial neural network (ANN) model was built for prediction. The area under the receiver operating characteristic (ROC) curve was 0.9409, indicating that the model had an outstanding classification performance. The ANN model could predict oviposition events on the current day, and the output was a probability that could be informative to indicate the likelihood of an oviposition event for an individual breeder. In situations where total egg production was known for a group, the ANN model could predict the probability of daily oviposition events occurring of all individual birds and then rank them to choose those most likely to have laid an egg.


Assuntos
Galinhas , Oviposição , Ração Animal , Animais , Feminino , Redes Neurais de Computação , Probabilidade
3.
Poult Sci ; 100(6): 101090, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33975037

RESUMO

Maternal growth patterns affect broiler growth performance. The current study investigated the impact of lesser growth restriction, compared to the breeder-recommended target growth, during the prepubertal growth phase and earlier pubertal growth in breeders on their offspring growth and carcass traits. In a randomized controlled trial, a total of 40 female broiler breeders were randomly assigned to 10 unique growth trajectories with 2 levels of maternal BW gain (MW) in prepubertal phase and 5 levels of maternal pubertal growth inflection (MI) for each level of the MW. Growth parameters (MW and MI) were estimated by fitting a 3-phase Gompertz model to the breeder-recommended BW target (Standard MW; SMW), or 10% higher (HMW). Maternal pubertal inflection was advanced by 0, 5, 10, 15, or 20% in both SMW and HMW groups. Maternal growth trajectories were implemented from 0 to 42 wk of age using a precision feeding (PF) system. The current study consisted of two cohorts that varied in maternal age (MA) of 35 and 42 wk. The broiler chicks were fed to 35 d of age, also with the PF system. Analysis of covariance was conducted on all dependent variables (BW, FCR, carcass traits) with MA, MW, and offspring sex as categorical variables and MI as a continuous predictor variable. Chicks from 42 wk old hens had higher 0 (hatch), 14, 21, and 28 d BW, liver, and heart weight, and lower FCR from 7 to 35 d of age than those from the 35 wk old hens. Compared to SMW hens, HMW hens produced female offspring with lower FCR, and male offspring with heavier gut weight. Advancing MI increased hatch BW in both sexes and 35 d BW in male broilers. For every week that the MI was advanced, hatch BW increased by 0.26 g in females and 0.39 g in males; however, 21 and 35 d BW decreased by 6.85 and 17.29 g/wk in females and increased by 10.53 and 25.94 g/wk in males, respectively. Overall, a lesser degree of growth restriction during prepubertal and earlier pubertal growth increased male offspring growth.


Assuntos
Galinhas , Fígado , Ração Animal/análise , Animais , Peso Corporal , Dieta , Feminino , Masculino
4.
Poult Sci ; 100(5): 101059, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33756248

RESUMO

Growth models describe body weight (BW) changes over time, allowing information from longitudinal measurements to be combined into a few parameters with biological interpretation. Nonlinear mixed models (NLMM) allow for the inclusion of random factors. Random factors can account for a relatively large subset of the total variance explained by bird-specific measurement correlation. The aim of this study was to evaluate different NLMM using birds from 2 heritage chicken lines; New Hampshire (NH) and Brown Leghorn (BL). A total of 32 birds (16 mixed sex birds from each strain) were raised to 17 wk of age. After 12 wk, half were continued on ad libitum (AL) feed intake, and half were pair-fed, using a precision feeding system; they were given 95% of the AL intake of a paired bird closest in BW. Residual feed intake (RFI) of birds, as an indicator of production efficiency, was increased in pair-fed BL birds as a result of minor feed restriction. Growth data of the birds were fit to a mixed Gompertz model with a variety of different bird-specific random coefficients. The model had the form: [Formula: see text] ; where Wm was the mature BW, b was the rate of maturing, t was age (d), tinf was the inflection point (d). This fixed-effects model was compared with NLMM using model evaluation criteria to evaluate relative model suitability. Random coefficients, Wmu âˆ¼ N(0,VWm) and bu âˆ¼ N(0,Vb), were tested separately and together and their differences, for strains, sex, and feeding treatments, were reported as different where P ≤ 0.05. The model with both random coefficients was determined to be the most parsimonious model, based on an assessment of serial correlation of the residuals. NLMM coefficients allow stochastic prediction of the mean age and its variation that birds need to achieve a certain BW, allowing for unique new decision support modeling applications; these could be used in stochastic modeling to evaluate the economic impact of management decisions.


Assuntos
Galinhas , Ingestão de Alimentos , Ração Animal/análise , Animais , Peso Corporal , Galinhas/genética , Dinâmica não Linear
5.
Front Physiol ; 11: 707, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670092

RESUMO

While photoperiod has been generally accepted as the primary if not the exclusive cue to stimulate reproduction in photoperiodic breeders such as the laying hen, current knowledge suggests that metabolism, and/or body composition can also play an influential role to control the hypothalamic-pituitary gonadal (HPG)-axis. This review thus intends to first describe how photoperiodic and metabolic cues can impact the HPG axis, then explore and propose potential common pathways and mechanisms through which both cues could be integrated. Photostimulation refers to a perceived increase in day-length resulting in the stimulation of the HPG. While photoreceptors are present in the retina of the eye and the pineal gland, it is the deep brain photoreceptors (DBPs) located in the hypothalamus that have been identified as the potential mediators of photostimulation, including melanopsin (OPN4), neuropsin (OPN5), and vertebrate-ancient opsin (VA-Opsin). Here, we present the current state of knowledge surrounding these DBPs, along with their individual and relative importance and, their possible downstream mechanisms of action to initiate the activation of the HPG axis. On the metabolic side, specific attention is placed on the hypothalamic integration of appetite control with the stimulatory (Gonadotropin Releasing Hormone; GnRH) and inhibitory (Gonadotropin Inhibitory Hormone; GnIH) neuropeptides involved in the control of the HPG axis. Specifically, the impact of orexigenic peptides agouti-related peptide (AgRP), and neuropeptide Y (NPY), as well as the anorexigenic peptides pro-opiomelanocortin (POMC), and cocaine-and amphetamine regulated transcript (CART) is reviewed. Furthermore, beyond hypothalamic control, several metabolic factors involved in the control of body weight and composition are also presented as possible modulators of reproduction at all three levels of the HPG axis. These include peroxisome proliferator-activated receptor gamma (PPAR-γ) for its impact in liver metabolism during the switch from growth to reproduction, adiponectin as a potential modulator of ovarian development and follicular maturation, as well as growth hormone (GH), and leptin (LEP).

6.
Anim Reprod Sci ; 213: 106257, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31987318

RESUMO

Chicken meat production relies on successful reproduction in broiler breeders. Challenges with feed restriction and metabolic dysregulation of reproduction in broiler breeders warrant conducting further research and developing of new management strategies in broiler production enterprises. This review, therefore, provides an overview of the underlying mechanisms of egg production and its (dys)regulation in broiler breeders and how management regimens affect these mechanisms. The review addresses the current knowledge of diurnal processes in sexually mature hens and the maturation process before the onset of diurnal cycles of reproduction. The important factors related to seasonal changes in reproduction are addressed, and two main factors involved, photorefractoriness and metabolic status, are highlighted. In addition, with this review it was ascertained that there is a lack of knowledge with relation to the current metabolic problems in broiler breeders.


Assuntos
Galinhas/fisiologia , Ritmo Circadiano , Estações do Ano , Animais , Galinhas/genética , Feminino , Oviposição
7.
Poult Sci ; 97(11): 3921-3937, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29945207

RESUMO

A precision feeding (PF) system was developed to increase broiler breeder lifetime reproductive performance through improved flock uniformity. The current study consisted of 2 rearing and 3 laying treatments. From 0 to 22 wk of age, 480 Cobb male grandparent line pullets and 80 Cobb MX males were fed once daily as a group (CON), or individually with a PF system. Pullets were housed in 6 replicate pens of 40 birds, and cockerels in one pen per treatment. During lay, CON and PF treatments continued, and a third treatment was added, where PF-reared birds were transitioned to conventional feeding (PFCON; n = 3 pens). At photostimulation (22 wk of age), all pens had 24 hens and 2 roosters. Birds were allowed to mate naturally to 52 wk. Analysis of variance was conducted, and Tukey-adjusted means were reported as different where P ≤ 0.05. Mean BW was near the target BW in all treatments. At photostimulation, PF pullet BW CV was 2% vs 14% in CON pullets. Cumulative feed conversion ratio during rearing was lower in PF treatment pullets, which ate 3% less than CON pullets. Pullets in the PF treatment received 10 meals spread throughout each day, compared with one meal per day in the CON treatment. Increased feeding frequency would reduce diurnal fluctuations in nutrient supply, which may explain why PF pullets had 1.2 times the breast muscle weight of CON pullets at 22 wk. There was no treatment difference in abdominal fatpad weight at 22 wk. The PF treatment had 3.8% higher fertility and 1.3% lower egg weight CV compared with the CON treatment. Egg production in PF and PFCON treatments was 0.73 and 0.89 times that of the CON treatment, respectively. It is hypothesized that metabolic changes in PF pullets provided an insufficient metabolic trigger for sexual maturation. It follows that relaxing feed restriction may increase fat deposition and egg production in PF broiler breeders.


Assuntos
Ração Animal/análise , Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Fertilidade , Reprodução , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/crescimento & desenvolvimento , Feminino , Masculino , Óvulo , Estimulação Luminosa , Distribuição Aleatória
8.
Sci Total Environ ; 630: 302-307, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29477827

RESUMO

Roxarsone (rox), an arsenic (As) containing organic compound, is a common feed additive used in poultry production. To determine if As present in rox is excreted into the poultry litter without any retention in chicken meat for safe human consumption, the transference of As from the feed to poultry excreta was assessed using two commercial chicken strains fed with and without dietary rox. The results revealed that both the strains had similar behaviour in growth (chicken weight; 2.17-2.25kg), feed consumption (282-300kgpen-1 initially containing 102 chicken) and poultry litter production (73-81kgpen-1) during the growth phase of 35days. Our mass balance calculations showed that chickens ingested 2669-2730mg As with the feed and excreted out 2362-2896mg As in poultry litter during the growth period of 28days when As containing feed was used, yielding As recovery between 86 and 108%. Though our complementary studies show that residual arsenic species in rox-fed chicken meat may have relevance to human exposure, insignificant retention of total As in the chicken meat substantiates our mass balance results. The results are important in evaluating the fate of feed additive used in poultry production and its potential environmental implications if As containing poultry litter is applied to soil for crop production.


Assuntos
Ração Animal/análise , Arsênio/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Esterco/análise , Animais , Aves Domésticas
9.
Environ Health Perspect ; 124(8): 1174-81, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26992196

RESUMO

BACKGROUND: Chicken meat has the highest per capita consumption among all meat types in North America. The practice of feeding 3-nitro-4-hydroxyphenylarsonic acid (Roxarsone, Rox) to chickens lasted for more than 60 years. However, the fate of Rox and arsenic metabolites remaining in chicken are poorly understood. OBJECTIVES: We aimed to determine the elimination of Rox and metabolites from chickens and quantify the remaining arsenic species in chicken meat, providing necessary information for meaningful exposure assessment. METHODS: We have conducted a 35-day feeding experiment involving 1,600 chickens, of which half were control and the other half were fed a Rox-supplemented diet for the first 28 days and then a Rox-free diet for the final 7 days. We quantified the concentrations of individual arsenic species in the breast meat of 229 chickens. RESULTS: Rox, arsenobetaine, arsenite, monomethylarsonic acid, dimethylarsinic acid, and a new arsenic metabolite, were detected in breast meat from chickens fed Rox. The concentrations of arsenic species, except arsenobetaine, were significantly higher in the Rox-fed than in the control chickens. The half-lives of elimination of these arsenic species were 0.4-1 day. Seven days after termination of Rox feeding, the concentrations of arsenite (3.1 µg/kg), Rox (0.4 µg/kg), and a new arsenic metabolite (0.8 µg/kg) were significantly higher in the Rox-fed chickens than in the control. CONCLUSION: Feeding of Rox to chickens increased the concentrations of five arsenic species in breast meat. Although most arsenic species were excreted rapidly when the feeding of Rox stopped, arsenic species remaining in the Rox-fed chickens were higher than the background levels. CITATION: Liu Q, Peng H, Lu X, Zuidhof MJ, Li XF, Le XC. 2016. Arsenic species in chicken breast: temporal variations of metabolites, elimination kinetics, and residual concentrations. Environ Health Perspect 124:1174-1181; http://dx.doi.org/10.1289/ehp.1510530.


Assuntos
Arsênio/análise , Galinhas/metabolismo , Poluentes Ambientais/análise , Contaminação de Alimentos/estatística & dados numéricos , Carne/análise , Animais , Arsênio/metabolismo , Dieta , Poluentes Ambientais/metabolismo , Humanos , Cinética , América do Norte
10.
Environ Sci Technol ; 50(13): 6737-43, 2016 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-26876684

RESUMO

The poultry industry has used organoarsenicals, such as 3-nitro-4-hydroxyphenylarsonic acid (Roxarsone, ROX), to prevent disease and to promote growth. Although previous studies have analyzed arsenic species in chicken litter after composting or after application to agricultural lands, it is not clear what arsenic species were excreted by chickens before biotransformation of arsenic species during composting. We describe here the identification and quantitation of arsenic species in chicken litter repeatedly collected on days 14, 24, 28, 30, and 35 of a Roxarsone-feeding study involving 1600 chickens of two strains. High performance liquid chromatography separation with simultaneous detection by both inductively coupled plasma mass spectrometry and electrospray ionization tandem mass spectrometry provided complementary information necessary for the identification and quantitation of arsenic species. A new metabolite, N-acetyl-4-hydroxy-m-arsanilic acid (N-AHAA), was identified, and it accounted for 3-12% of total arsenic. Speciation analyses of litter samples collected from ROX-fed chickens on days 14, 24, 28, 30, and 35 showed the presence of N-AHAA, 3-amino-4-hydroxyphenylarsonic acid (3-AHPAA), inorganic arsenite (As(III)), arsenate (As(V)), monomethylarsonic acid (MMA(V)), dimethylarsinic acid (DMA(V)), and ROX. 3-AHPAA accounted for 3-19% of the total arsenic. Inorganic arsenicals (the sum of As(III) and As(V)) comprised 2-6% (mean 3.5%) of total arsenic. Our results on the detection of inorganic arsenicals, methylarsenicals, 3-AHPAA, and N-AHAA in the chicken litter support recent findings that ROX is actually metabolized by the chicken or its gut microbiome. The presence of the toxic metabolites in chicken litter is environmentally relevant as chicken litter is commonly used as fertilizer.


Assuntos
Arsênio , Roxarsona , Animais , Ácido Arsanílico , Arsenicais , Ácido Cacodílico/metabolismo , Galinhas/metabolismo
11.
J Chromatogr A ; 1370: 40-9, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25459646

RESUMO

Human exposure to high concentrations of arsenic from water and food is an important health concern. Although 3-nitro-4-hydroxyphenylarsonic acid (Roxarsone) was used for more than 60 years as a feed additive to feed chickens, little is known about the metabolism of this arsenic species in chicken. Determination of potential arsenic metabolites present at trace concentrations is an analytical challenge, requiring efficient separation and sensitive detection. The primary objective of this research is to develop a method that enables the identification and quantification of various arsenic species in chicken liver. This report describes a method of high performance liquid chromatography (HPLC) separation with both inductively coupled plasma mass spectrometry (ICPMS) and electrospray ionization tandem mass spectrometry (ESI-MS/MS) detection. Anion exchange HPLC enabled the separation of Roxarsone and other arsenic species within 12 min. Detection with both ICPMS and ESI-MS/MS allowed for identification and quantification of eight arsenic species in chicken livers, including arsenobetaine, inorganic arsenite, dimethylarsinic acid, monomethylarsonic acid, inorganic arsenate, 3-amino-4-hydroxyphenylarsonic acid, N-acetyl-4-hydroxyphenylarsonic acid (N-AHPAA), and Roxarsone. The concentrations of these arsenic species, with the exception of arsenobetaine, are significantly higher in the Roxarsone-fed chickens than in the control chickens. The simultaneous detection by both ICPMS and ESIMS from the same HPLC separation allowed for comparison of peaks in both ICPMS and ESIMS chromatograms. This is advantageous over two separate analyses, particularly when HPLC retention times might fluctuate due to sample matrix effect. HPLC separation with the complementary atomic and molecular mass spectrometry detection prevented misidentification of co-eluting compounds, as demonstrated by the determination of two possible metabolites of Roxarsone, N-AHPAA and 4-amino-phenylarsonic acid (4-APAA). N-AHPAA was confirmed by HPLC separation with simultaneous arsenic-specific detection by ICPMS and multiple reaction monitoring by ESIMS. Although an arsenic-containing compound had identical retention time as 4-APAA in the HPLC­ICPMS chromatogram, it was ruled out as 4-APAA from the simultaneous detection by ESIMS. The identification and quantitation of trace arsenic species present in complex samples demonstrate the potential of HPLC separation with simultaneous ICPMS and ESIMS detection for other speciation applications.


Assuntos
Arsênio/análise , Cromatografia Líquida de Alta Pressão/métodos , Fígado/química , Espectrometria de Massas em Tandem/métodos , Animais , Galinhas , Limite de Detecção
12.
J Agric Food Chem ; 61(47): 11595-602, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24164329

RESUMO

Omega-3 polyunsaturated fatty acids (n-3 PUFA) enriched eggs have a growing market share in the egg industry. This study examined the stability of n-3 PUFA enriched eggs fortified with antioxidants (vitamin E or organic Selenium [Sel-Plex] or both) following cooking and storage. The total fat content was not affected by cooking or simulated retail storage conditions, whereas, n-3 fatty acids were reduced. The content of n-3 fatty acids in boiled eggs was higher than in fried eggs. Lipid oxidation was significantly affected by the different cooking methods. Fried eggs contained higher levels of malondialdehyde (MDA, 2.02 µg/kg) and cholesterol oxidation products (COPs, 13.58 µg/g) compared to boiled (1.44 and 10.15 µg/kg) and raw eggs (0.95 and 9.03 µg/kg, respectively, for MDA and COPs). Supplementation of antioxidants reduced the formation of MDA by 40% and COPs by 12% in fried eggs. Although the content of MDA was significantly increased after 28 days of storage, COPs were not affected by storage. Our study indicated that the n-3 PUFA in enriched eggs was relatively stable during storage and home cooking in the presence of antioxidants.


Assuntos
Ração Animal , Ovos , Ácidos Graxos Ômega-3/química , Alimentos Fortificados , Animais , Antioxidantes/química , Galinhas , Colesterol/química , Culinária , Ácidos Graxos Ômega-3/análise , Feminino , Malondialdeído/química , Oxirredução , Selênio/farmacologia , Vitamina E/farmacologia
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