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Breeder and Hatchery Factors Impact Broiler Performance

01 April 2015

New research presented at the International Poultry Scientific Forum in Atlanta, Georgia, US, earlier this year explored the effects of broiler breeder and hatchery management on the hatchability of chicks and subsequent broiler performance.

Egg Storage Time Impacts Hatchability

The storage of eggs has more impact on egg hatchability than on grow-out performance, according to new research at the University of Arkansas. However, where the egg was laid (floor or nest) has no significant effect

Graduate student, Emily Lhamon, explained to the Forum that the objective of the study1 was to determine the effects of egg treatment and handling on the viability and efficiency of Cobb broilers.

She reported two experiments: egg storage duration and floor versus nest eggs. In the egg storage trial, eggs were collected from the same flock and stored for four, eight, 12 or 16 days.

In the floor versus nest egg trial, eggs were collected from a flock notorious for laying outside of the nest box and from a sister flock that laid inside the nest box.

An initial trial and a replicate were performed for each experiment.

For the egg storage Trial 1, significant differences were found in percent hatch, percent hatch of fertile and percent fertility.

In Trial 2, there were significant differences in feed conversion ratio for weeks 1 and 2, average bird weight at placement, percent hatch, percent hatch of fertile and percent fertility.

No statistical differences were found for any of the criteria in either trial of the floor versus nest egg treatments.

Effects of Breeder Age on Egg Yolk Composition Examined

The effects of breeder age on yolk fatty acid composition and yolk absorption during embryonic development have been explored by Nirun Boonsinchai of the University of Arkansas and others with Charoen Pokphand Food and at Sukhothai Thammathirat Open University in Thailand2.

They found that the rate of yolk absorption was higher in embryo from younger hens but the concentration of yolk fatty acids and there was more available yolk for the embryo from older breeders, thus providing more fat for embryo gain and livability.

The researchers commented that the higher amount of residual yolk at hatch together with its higher concentrations of fatty acid contents in chicks hatched from older hens may result in the better growth rate that has frequently been observed in practice.

Feeding Programme During Rearing Affects Breeder Body Composition

Another experiment at the University of Arkansas investigated the effects of four different feeding programmes from rearing period to sexual maturity on protein turnover in parent stock broiler breeders3.

Karen Vignale explained that the four feeding programmes they used were based on body weight curves: everyday feeding, skip-a-day feeding (Cobb Standard body weight curve), under-feeding (body weight curve 20 per cent below standard) and over-feeding (body weight curve 20 per cent above standard).

There was a large increase in fractional protein breakdown rate during the transition for the pullet to sexual maturity, and there were further increases in the rate until peak egg production, which is related to the decreased percentage lean mass body content during this period of time, she added.

From their results, the Fayetteville-based researchers concluded that broiler breeders may rely on skeletal muscle tissue as a source of nutrients for egg production, especially during the early laying period.

Broiler Performance Affected by Feed Mineral Source and Incubation Humidity

The effects of incubation conditions and trace mineral source in broiler breeder and broiler progeny diets on the live performance of Ross 708 male broilers were investigated by researchers at North Carolina State University, Nutreco in the US and Canada and Selko Feed Additives in the Netherlands4.

The breeders and their progeny received the same trace mineral sources: all-organic, all-inorganic and mixed organic and inorganic.

Relative humidity during incubation affected the bodyweight of the chicks at placement, explained graduate student, Coltin Caraway. Those incubated at 70 per cent humidity were heavier than those incubated at 53 per cent relative humidity.

At 42 days of age, trace mineral source affected bodyweight, with those receiving the mix the heaviest, and the lightest birds were those fed the organic-only minerals. Feed intake reflected the same pattern.

Incubation at higher relative humidity decreased feed intake in the broilers receiving the inorganic trace minerals and this resulted in a significant decrease in 28-day bodyweight.

There were no significant effects, however, on feed intake or bodyweight due to incubation at higher humidity for the broilers receiving the organic or mixed trace minerals.

At 42 days of age, the best feed conversion was achieved by the organic trace minerals incubated at low relative humidity.

Incubation Temperature Affects Litter Moisture in Broilers

Incubation temperature profiles affect live performance and footpad dermatitis (FPD), explained Albaraa Sarsour in the introduction to a paper from North Carolina State University5.

In two experiments, they evaluated the effects of incubation temperature profile on litter moisture, finding that the effect was indirect.

Two factorial arrangements of treatments were used. In Experiment 1, eggs from hens of three genetic lines with different FPD incidence were subjected to two incubation temperature profiles.

In Experiment 2, eggs from Cobb 500 hens were incubated under three incubation temperature profiles and placed in floor pens with either new wood shavings or used litter.

In both experiments, the first incubation temperature profile treatment maintained eggshell temperatures close to 38.0°C (S) for 21 days. The second profile (LH) had low (36.9°C) eggshell temperatures for the first three days, and standard incubation temperature profile until the last three days when eggs were subjected to elevated (38.9°C) eggshell incubation temperature profile (H), as is observed in multistage machines.

For Experiment 2, the third incubation temperature profile (SH) had S INC until the last three days, when eggs had H incubation temperature profile.

At hatch, 180 or 210 broilers per treatment combination, respectively, were placed in 15 pens with either new pine wood shavings in Experiment 1, and with new or used litter in Experiment 2.

In both experiments, incubation temperature profile consistently affected litter moisture.

In Experiment 1, litter moisture was one to two percentage points higher for the S treatment at 13 and 28 days of age but at 42 days, this situation reversed and pens containing broilers from the LH treatment had higher litter moisture.

In Experiment 2, pens with chickens from the S incubation temperature profile had the lowest litter moisture, which was similar to the LH incubation temperature profile only at 37 days.

One interaction was observed with genetics in Experiment 1 at 28 days and interaction effects with litter type were detected in Experiment 2.

While higher litter moisture in Experiment 1 was associated with higher broiler feed intake and bodyweight gain, this link was not evident in Experiment 2.

Effects on Broiler Performance of Vaccination Method and Pre-placement Holding Time

The effects of in-ovo or subcutaneous vaccination of HVT vaccine and four and 18 hours pre-placement holding times on the performance of male broilers to 48 days of age have been investigated by researchers at Mississippi State University and Zoetis Inc.6

At the Forum, David Peebles explained that Aviagen 708 broiler hatching eggs were either in-ovo-vaccinated at 18 days of incubation or chicks were vaccinated subcutaneously at hatch, and chicks from each vaccination treatment group were held for one of the two holding times.

No interactions were observed between vaccination and holding time for any parameter. However, a main effect of vaccination was observed for 14- to 28-day feed consumption.

Holding time effects were observed for feed intake from days 0 to 14 and 14 to 28 as well as for bodyweight gain from days 0 to 7 and 14 to 21.

Feed consumption from days 14 to 28 of birds vaccinated subcutaneously was lower than that of in-ovo-vaccinated birds, and the increase in holding time from four to 18 hours decreased feed intake and bodyweight gain for all four time periods.

Peebles and colleagues concluded that an increase in holding time decreased bodyweight gain by reducing feed intake to 28 days of age. Furthermore, in-ovo injection did not negatively affect broiler performance to 48 days of age, whether broilers were held for four or 18 hours prior to placement.

The researchers added that, with respect to broiler performance, in-ovo and subcutaneous injections were equally safe for the administration of the HVT vaccine.

Benefits of Administering Probiotics in the Hatchery

Treatment with a probiotic in the hatchery provides a unique opportunity to colonise neonatal broilers with beneficial microbes that have multiple beneficial effects including an increase in seven-day weight, decreased mortality, improved uniformity and early protection from pathogens.

Those were the conclusions of researchers Ross Wolfenden and colleagues at Pacific Vet Group from the experiment they reported at the Forum7.

He explained that early gut development in broiler chicks is stimulated by the establishment of healthy gut microflora. In nature, hens provide these microflora to their chicks, however, in the commercial setting, hens and progeny are separated which prevents colonisation by the normal flora. This retards intestinal development and can leave the chicks more susceptible to pathogenic bacteria, which in turn decrease market weight and increase mortality.

The first organisms to colonise the GI tract have a distinct advantage in becoming the primary residents. However, the most common environmental bacteria in the hatchery and farms often include species such as Pseudomonas, Salmonella and E. coli which may be pathogenic.

In their study, a novel, hatchery-applied probiotic (FloraStart®) was evaluated to determine its effects on seven-day weight gain, uniformity and mortality in broiler chicks.

Chicks were treated with the probiotic, which is comprised of Lactobacillus plantarum strain TY036 and Enterococcus faecium strain MFF109, via spray in the hatchery prior to placement in commercial broiler houses.

The probiotic treatment led to a decrease in flock mortality from 4.97 to 4.50 per cent. There was also a significant increase in seven-day bodyweight, and better flock uniformity, the researchers observed.

The same group at the Pacific Vet Group reported their investigation into the effects of administering the probiotic with concomitant administration of anticoccidial vaccines8.

Matthew Faulkner said that while effective at establishing immunity against Eimeria sp., the vaccines have been known to decrease early growth rate and leave chicks more susceptible to secondary bacterial infections within the gut.

He and his colleagues found that the administration of the probiotic led to increased bodyweight gain in chicks vaccinated against coccidiosis.

The researchers again used FloraStartC applied in the hatchery. They performed multiple in-vivo experiments using multiple commercially available coccidiosis vaccines and, in each experiment, the birds were weighed on day-of-hatch and days 7, 10, and 14 to determine weight gain compared to non-probiotic treated chicks.

In all experiments, the probiotic-treated groups consistently had greater weight gain than non-probiotic treated groups for all time periods.


  1. Lhamon E., D.E. Yoho, L. Butler and R.K. Bramwell. Comprehensive study of the effects of egg storage, floor and nest eggs, and broiler breeder flock age on hatchability and 14-day livability, feed conversion ratio, and body weight in broiler chicks.
  2. Boonsinchai N., J. Caldas, P. Sodsee, K. Vignale, M. Putsakum, E. Holt, A. Magnuson, J. Wang, J. England and C. Coon. Effects of breeder age on yolk fatty acid composition and yolk absorption during embryonic development.
  3. Vignale. K., J.V. Caldas, J. England, N. Boonsinchai, P. Sodsee, E.D. Pollock, S.Dridi and C.N. Coon. The effect of four different feeding programs from rearing period to sexual maturity on protein turnover in parent stock broiler breeders
  4. Caraway C., S. Homen, G. Page, W. Litjens and J. Brake. The effects of incubation conditions and trace mineral source in broiler breeder and broiler progeny diets on the live performance of Ross 708 male broilers.
  5. Sarsour A., E. Oviedo-Rondón and J. Scott. Incubation temperature profiles affect litter moisture in broilers.
  6. Peebles E.D., T. Barbosa, T. Cummings, J. Dickson and S. Womack. 1 Comparative effects of in ovo versus subcutaneous vaccination and pre-placement holding time on post-hatch broiler performance.
  7. Wolfenden R., M. Faulkner, A. Menconi, J. Barton, J. Lum, and J. Vicente. Application of a specifically selected probiotic at the hatchery improves seven day weight gain as well as mortality in commercial broiler chicks.
  8. Faulkner M., J. Lum, J. Vicente and R. Wolfenden. Minimizing reduction in average daily gain in broiler chicks following the use of anticoccidial vaccines through concomitant treatment with a lactic acid bacteria-based probiotic.

April 2015

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