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Hulless oats are of interest as an alternative to corn and wheat in organic poultry diets because they offer potential to enhance agrobiodiversity and produce locally grown feeds both within and outside of corn-growing regions. Hulless oats are easily certified GM-free and have demonstrated nutritional value for poultry. A feeding study was carried out to examine: (i) the effects of substituting corn, wheat or a fraction of each with hulless oats in organic layer diets, and (ii) the importance of oat variety in feed performance. Productivity and economic implications in the context of current organic markets were explored. Experimental diets included an oat-free control, Oat + corn, Oat + wheat and Oat + corn + wheat, each of which was formulated with three hulless oat varieties, AC Gwen, Paul and Streaker. All but the control diet included oats at 200 g kg−1. Three hundred Hy-Line Brown hens were individually caged and allocated to diets in groups of 10 in a completely randomized design with three replicates per diet. Experimental diets were fed between 24 and 32 weeks of age during which time hen health, egg production and egg quality indicators were monitored. Results indicated that hulless oats had no negative effects on hen health and productivity. On the basis of current organic feed ingredient prices and an estimated cost of USD 533 mt−1 for production of oats in the study region, oat containing diets were more expensive than the oat-free control. In an evaluation of revenue based on current market prices for organic eggs, the additional cost was completely offset by larger egg sizes of hens on oat containing diets. There were no major differences associated with oat variety.

US organic poultry producers are under pressure to find feed alternatives to corn and wheat. Hulless oats offer advantages such as wide geographic adaptation of the plant and high concentrations of protein and oil in the grain. They have shown considerable potential in experimental work as a feed grain for poultry, but more research is needed into their influence on the sensory and nutritional properties of eggs. In this study, hulless oats were substituted for corn or wheat at 200 g kg−1 in diets fed to Hy-Line Brown hens and eggs were sampled for sensory evaluation after 8 weeks. Discrimination tests of blended and baked egg samples found evidence of difference between eggs from oat-based diets and those from the oat-free control (p < 0.05 for eggs from an oat-corn diet, p < 0.01 for eggs from an oat-wheat diet). Acceptance tests of similar samples showed that eggs from the oat-wheat diet were significantly less liked than control eggs for their texture (p < 0.01) and response to cooking (p < 0.01), while eggs from the oat-corn diet were somewhat less liked. Yolk weight was greater (p < 0.05) in control eggs (34.1 g) than eggs from oat-corn (31.6 g) or oat-wheat (31.2 g) diets, leading to smaller yolk proportion in the oat-fed eggs. Fatty acid profile differences across treatments were not of nutritional significance, and no evidence was found that the feeding of hulless oats improved storage properties of eggs. In this study, modifying the carbohydrate source in layer diets was shown to change textural properties of cooked eggs in a way that was perceptible to untrained consumers, probably by reducing the yolk proportion. This finding was not commercially relevant owing to small effect size, and results overall add to existing evidence that hulless oats can be fed to poultry at a moderate proportion of the diet with no negative effect on consumer acceptability of eggs. Regardless of the small effect size, however, findings are interesting from the food chemistry perspective because they provide novel evidence of how the thermal properties of eggs can be altered by a change in hen dietary carbohydrate source.

Three hundred Red-legged partridge chicks (Alectoris graeca) were divided into two groups and fed starter diets calculated to contain 24.5 and 24.9% crude protein and 2646 and 2662 kcal/kg metabolizable energy, respectively. One diet consisted of 5% fish meal while the other contained all vegetable protein. One-half of the birds on each diet were grown under fluorescent light intensity of 300 lx; the remainder received 5 lx. The results indicated that neither the source of protein nor intensity of light had an effect on the rate of growth to 8 weeks of age. At 8 weeks of age, the birds were randomly divided among three climatic chambers and kept under a constant temperature of either 18.3, 23.9, or 29.5 C. At 12 weeks of age, one-half of the birds in each chamber were fed a 20% turkey grower diet; the remainder received equal parts by weight of the turkey grower diet and whole milo. Individual body weights and feed consumption were measured biweekly. Best growth was obtained in birds kept at 29.5 C and fed equal parts of turkey grower and milo from 12 to 30 weeks of age.

Reproductive response was measured in two lines of chukar partridge given conditioning light treatments of either 8 hr light:16 hr dark (8L:16D) at 50 lx or 16L:8D at .1 lx for 4, 6, or 8 weeks, respectively. Birds were recycled to lay using the same conditioning light treatments. During both lay cycles, all birds received 16L:8D at 100 lx. The results indicate that both conditioning light regimens were effective in terminating postjuvenile and postlay refractoriness. Hens given a conditioning light treatment of 8L:16D at 50 lx reached sexual maturity earlier, and produced more eggs and more viable chicks, and males maintained fertility longer, compared to birds conditioned under 16L:8D at .1 lx. Light conditioning periods of 6 and 8 weeks were superior to those of 4 weeks. For maximum reproductive performance in partridges, a short day photoperiod of 8L:16D at 50 lx is recommended for successful interruption of either postjuvenile or postlay refractoriness.

Shank length measurement of greater than or equal to 60 mm for males and less than 60 mm for females was used to predict sexes in male and female chukar partridges (Alectoris chukar) at 8, 10, 12, 20, 32, and 64 weeks of age. Growth of the shank is nearly complete at 10 weeks of age, whereas growth of body tissue continues to about 20 weeks of age. The best prediction of sexes was made at 10 weeks of age with an accuracy of about 95%. At 10 weeks of age, the accuracy for predicting males was higher than for females (98.5% vs 93%). At 64 weeks of age, best accuracy of sexes was made using a shank measurement of greater than or equal 61 mm for males and less than 61 mm for females. This technique to differentiate between sexes requires only a single shank measurement taken at 10 weeks of age and provides the grower and avian biologist with a reliable way of separating sexes for purposes of marketing, restoration, or selection of breeders at early ages.

The effects of temperature and dietary energy on various reproductive parameters were studied in Red-Legged partridges (Alectoris graeca) reared in three environmental chambers at either 18.3, 23.9, or 29.5 C. These birds were then cycled through two consecutive production periods. In Period 1, at 38 weeks of age, the birds in each chamber, 118 pair total, were divided into four subgroups and fed a diet containing either 2600, 2800, 3000, or 3200 kcal/kg of metabolizable energy. The energy to protein ratio was held constant at 186. In Period 2, at 63 weeks of age, chambers with the lowest and highest temperatures were changed from 18.3 to 15.6 C and 29.5 to 32.2 C, respectively. Only the lowest and highest energy diets were used. In both periods, the birds kept at higher temperatures and fed the high energy diets consumed significantly less feed (P less than .05) than the other comparable groups. Hatchability was significantly higher (P less than .05) in groups fed the 3000 and 3200 kcal/kg diets as compared to the 2600 kcal/kg diet group. In Period 2, egg production increased in all groups, but birds kept at 32.2 C laid significantly fewer (P less than .05) eggs per bird than those kept at 15.6 and 23.9 C, respectively. The best performance, as measured by salable chicks produced per hen, was obtained in the group kept under a constant temperature of 23.9 C and fed the high energy diet (3200 kcal/kg).