The use of fractionated protein-vitamin flour from wheat bran in the diets of quails

The results of the experiment on the use of protein-vitamin flour from wheat bran, divided into fractions with particle size of 140, 400 and 800 µm in the diet of domesticated quails are presented. The experiment lasted for 60 days and was carried out according to the generally accepted methods on quails of the Japanese breed, formed in four similar groups (one control and three experimental), 80 heads each, at the age of one-day old. All groups received compound feed (the main diet), prepared taking into account the age and physiological characteristics of quails, but in the bird diet of the 1st, 2nd and 3rd experimental groups, part of the wheat (7%) was replaced with wheat protein-vitamin flour of three fractions with a particle size of 140, 400 and 800 µm, respectively. The poultry was kept in a battery cage under required microclimate conditions. The effect of feeding fractionated protein-vitamin flour from wheat bran was studied on the survival rate of quail chicks, their growth rate, indicators of meat productivity and hematological parameters, changes in the species composition of microorganisms of the gastrointestinal tract. The optimal fractions of wheat bran flour as the new feed in the diets of quails were determined in terms of efficiency of their productive and physiological action. The introduction of protein-vitamin flour from wheat bran into the compound feed of quails with a particle size of 140 and 400 µm in the amount of 7% of the grain part of the diet increased the survival rate of quail chicks by 3.0%, the average daily gain in live weight by 2.30 and 5.59%, the weight of eviscerated bird carcass by 4.5 and 6.16%, protein content in meat by 0.84 and 0.57%. Feeding the quails with flour of various fractions did not have a positive effect on the conversion of feed into produce. The biochemical parameters of the quail chicks’ blood remained within the physiological norm. Fractionated protein-vitamin flour with a particle size of 400 and 800 µm stimulated the growth of bifidobacteria, and with a particle size of 140 and 800 µm inhibited the development of Escherichia coli.

Effect of Breed and Diet Type on the Freshness and Quality of the Eggs: A Comparison between Mos (Indigenous Galician Breed) and Isa Brown Hens

Eggs are a nutritious food, offering a balanced source of essential amino and fatty acids, minerals, and vitamins. Genetic and diet factors can modify hen egg traits. Thus, the effects of breed and feed on egg quality using two laying hens, Mos (autochthonous breed) and Isa Brown (commercial hybrid), and three feeds, commercial fodder (CF), corn/pea/triticale (CPT) and corn/wheat (CW), were investigated. Freshness parameters (egg weight, eggshell weight and thickness, albumen height, Haugh units and yolk color), chemical composition, color and textural parameters, as well as fatty acid profile, were assessed on a total of 288 eggs, from the two breeds. The samples were divided in 96 eggs, corresponding to each of the three dietary treatments. There were significant differences (p < 0.001) in albumen height and Haugh units, obtaining the highest values for Isa Brown genotype; meanwhile, laying hens fed with CF had the highest weight, as well as the greatest eggshell thickness. Cooked yolks of Isa Brown eggs presented the highest values of luminosity, while the yellowness was higher for Mos eggs. Regarding the texture of eggs, genotype was again the parameter having the greatest impact, obtaining higher values in hardness, gumminess and chewiness in those eggs from the Mos breed. Concerning egg chemical composition, it was affected by breed and diet type, but Mos eggs were characterized by a significantly (p < 0.001) higher contents of fat (9.53% vs. 7.58%), protein (12.31% vs. 11.66%) and ash (1.10% vs. 1.04%) than Isa Brown ones. Finally, diet type influenced the fatty acid profile, mainly affecting oleic and linoleic acids, which showed significantly (p < 0.05) highest values (42.90 and 14.66 g/100 g of total fatty acids) in CW and CF diets, respectively. Overall, breed and bird diet factors had a strong effect on egg quality and nutritional profile. Moreover, eggs from Mos hens had more attractive nutritional indices, and they could even be improved more by changing the diet.

Context-dependent foraging by seed-eating birds does not necessarily mean low ecological predictability

Flexibility of foraging behaviour affects our capacity to predict ecological outputs such as population responses to habitat change. Some birds forage following rules of absolute value of the food item (i.e., absolute valuation). Their realized diet is strongly correlated with the profitability of the food item and it is predictable. Consumers, however, do not always follow absolute rules. Opportunistic foragers adjust food consumption based on the availability of the food item. Their diet is still predictable but more elusive. Relativistic or context-dependent foragers change the ranks of food preferences depending on the presence of alternative food options in the choice set. Predicting their contingent diet is particularly difficult. We tested if the context of seed availability affects foraging decisions of three seed-eating bird species (the Rufous-collared Sparrow (Zonotrichia capensis (Statius Muller, 1776)), the Many-colored Chaco Finch (Saltatricula multicolor (Burmeister, 1860)), and the Common Diuca Finch (Diuca diuca (Molina, 1782))) using choice experiments aimed at detecting if seed preferences for two types of target seeds changed according to context. Birds showed very similar rankings of preferences for target seeds; however, preferences for attractive food items were not fixed but often increased in less valuable contexts. Although results imply some degree of context-dependent behaviour, predictability of bird diet was preserved because the ranking of preferences remained mostly unchanged between contexts (and among bird species), and the higher consumption of target grass seeds in a less attractive context was widely expected from the intrinsic properties of the seeds.

Seed Preferences in Sparrow Species of the Monte Desert, Argentina: Implications for Seed-Granivore Interactions

We assessed seed preference in four species of sparrows that are common to the central Monte desert of Argentina. Our hypotheses are that (1) sparrows always prefer grass over forb seeds and (2) different species of sparrows show the same preferences when consuming seeds. We presented seeds from eight species of plants (four grasses and four forbs) in both choice and nonchoice experiments. In general, sparrow species preferred grass over forb seeds, though one of them (Rufous-collared Sparrow [Zonotrichia capensis]) included one forb species (Parthenium hysterophorus) among its preferred seed items. Among grass seeds, sparrows avoided or showed less preference for the tiny seeds of Sporobolus cryptandrus, which suggests that seed weight may affect seed choice among grasses. Avoidance of most forb species, by contrast, could not be associated with seed size, probably because of the presence of unpalatable or toxic compounds in forb seeds. Experimental evidence suggests that the main feeding pressure of sparrows is clearly directed to grass seeds, which coincides with reported information on bird diet. Results support assertions that sparrows can cause a negative effect on the composition and abundance of grass seeds in the soil seed-bank, a necessary condition for birds in playing a significant role on grass population dynamics in the central Monte desert of Argentina. Preferencias por Semillas de los Emberízidos del Desierto del Monte, Argentina: Implicancias para la Interacción Semillas-granívoros