Nutritional quality and amino acid composition of diets consumed by scavenging hens and cocks across seasons

Nutritional status and growth performance of Fijian non-descript local chickens and their crosses with broilers under different production systems

The study compared nutrient intake and growth performance of local chickens to that of local x broiler crossbreds under scavenging and indoor conventional systems. A total of 48 male and 48 female chickens for each of the two chicken types were allocated to four outdoor free-range pens. The chickens were allowed to scavenge whilst being supplemented with sorghum plus kitchen waste and broiler growers from week 5 to week 13 of age. The same design was repeated using the indoor conventional system. Local chickens and their crosses with broilers had higher growth rates under the scavenging system than the indoor production system (P < 0.05). Local chickens and their crosses with broilers had the same growth rates when fed the same diet (P > 0.05). Crop and gizzard contents from local chickens had the same crude protein as their crosses with broilers under both systems (P > 0.05). The crude protein values of crop and gizzard contents ranged from 25.4 to 30.4%. Crop and gizzard contents from scavenging chickens had energy content ranging from 16.2 to 17.1 MJ/Kg which was lower (P < 0.05) than that from chickens under the indoor conventional system (20.3 to 25.8 kJ/Kg). Iron content ranged from 655.7 to 1619.4 mg/Kg in scavenging chickens and 156.1 to 621.4 mg/Kg in enclosed chickens. Chickens of the same type had higher iron content in their crop and gizzard contents under the scavenging system than the conventional system (P < 0.05). Crossbreds between local chickens and broilers matches the scavenging abilities of the local chickens but have lower growth rates under the scavenging system.

Indigenous chicken production in Fiji Islands: Knowledge, constraints and opportunities

Objective

The objective of the study was to understand and document socio-economic characteristics, production parameters, challenges and management practices used by Fijian households which keep indigenous chickens.

Methods

A survey involving 200 households was carried out in coastal and inland communities of Fiji's wet and semi-dry ecoregions. Data on the influence of ecoregion and location of households relative to the sea on management practices, challenges and productivity of indigenous chickens were analyzed using logistic regression and general linear model of SAS software.

Results

Irrespective of location relative to the sea and ecoregion, households indicated that they kept indigenous chickens for food and income generation. The Welsummer was the most( P > 0.05) preferred breed. Households in the semi-dry inland communities had the largest (P < 0.05) flocks compared to those in semi-dry coastal communities and the wet region. Chickens in the semi-dry region performed better (P < 0.05) than those in the wet region in terms of number of clutches per year and mature live weight. Predators and feed shortages were the biggest challenges faced by households in all areas. The mongoose was ranked as the most (P > 0.05) common predator followed by domestic dogs. Most households in the wet ecoregion's coastal communities housed their chickens at night, whereas communities in semi-dry ecoregion housed their chickens most of the time (P < 0.05). In all regions, no households sold their chickens to commercial markets (P > 0.05). Households in semi-dry ecoregion were more likely (P > 0.05) to sell their chickens at the local market place.

Conclusion

The productivity of local chickens in Fiji is low because of feed shortage, predators such as the mongoose and lack of market linkages.

Effect of vegetation density on survival of South African free-ranging indigenous chicken broods

The survival of juveniles from hatching until recruitment is a critical determinant of indigenous chicken population growth under extensive free-range production systems. A longitudinal study was conducted to investigate the impact of vegetation cover on survival of indigenous chicken broods in Msinga, South Africa. Survival records of 281 chicks hatched in sparsely vegetated (SV) communal lands and 233 hatched chicks in densely vegetated (DV) resettlement areas were collected from hatch until 12 weeks of age. Data on probable cause of death of individual chicks was collected using a structured checklist. Kaplan-Meir survival distributions and log rank tests were used to estimate the survival functions of broods between vegetation cover types. Logistic regression analysis was used to determine the association between management factors and mortality risk in SV and DV. Chick survival from hatching to 12 weeks was higher in SV (55 ± 3.14%) than DV (41 ± 4.19%) (P < 0.05). Mean chick survival time did not differ between SV (56 ± 3.30 days) and DV (49 ± 3.23 days) (P > 0.05). Aerial predators were the major cause of chick mortality (over 60%) followed by terrestrial predators (30%) in both vegetation cover types. The odds of mortality were higher in DV compared to SV (P < 0.05). It was concluded that increasing vegetation cover decreases survival of scavenging chicks between hatching and end of brooding at 12 weeks of age, and therefore brood management actions should ensure adequate protection of free-ranging chicken broods in densely vegetated rearing habitats.

Expression of sex hormone receptors in the brain of male and female newly hatched chicks

Chromosomal sex and steroid hormones play a determining role in brain sexual differentiation during chick embryonic development. Hormone effects on the brain are associated with the expression pattern of their intracellular receptors, which is sexually dimorphic in many species. We determined by Western blot the content of progesterone, estrogen, and androgen receptors (PR-A and PR-B, ERα, and AR, respectively) in the cortex, cerebellum, tectum, and hypothalamus of female and male newly hatched chicks. Males presented a higher content of PR-B in the tectum whereas females exhibited a higher content of PR-A in the hypothalamus. ERα was only detected as a band of 66kDa, and it showed a higher content in the cerebellum and tectum of females as compared to these regions in males. Besides, males exhibited a higher content of AR in the tectum than females. Our study suggests that newly hatched chicks show a sexual dimorphism in the expression of sex hormone receptors in brain regions involved in sexual behavior such as the hypothalamus, and in non-sexual behavior such as the optic tectum and the cerebellum.