A total of 160 1-day-old ducklings (average initial body weight of 53 g), were used in a 42-d feeding trial to evaluate the effects of reducing nutrient density of diets, and supplementing the diets with a phytogenic blend (quillaja, anise, and thyme) on their growth, carcass quality, and nutrient digestibility. After checking body weight on d 1, the birds were sorted into pens with 5 birds/pen...

English × Continental heifers ( = 180) were sourced in 2 loads (219.3 ± 16.0 and 221.4 ± 16.4 kg, respectively) from commercial auction barns to study the effects of feeding dehydrated citrus pulp (DCP) on feedlot performance of newly received heifers. A completely randomized block design was used with BW nested within arrival load and blocked by BW into 3 dietary treatments (36 pens, 5 heifers...

Ninety weanling pigs in Exp. 1 (6.27 +/- 0.73 kg; 21 d of age) and 96 growing pigs in Exp. 2 (21.73 kg +/- 1.29 kg; 56 d of age) were used in two 42-d experiments to evaluate the effect of phenyllactic acid (PLA) on growth performance, apparent total tract digestibility (ATTD) of DM and N, fecal pH value, microbial shedding, and blood profiles. In Exp. 1, the 3 dietary treatments were 1) negati...

Feeding chickens diets high in n-3 fatty acids (FA) increases their incorporation into tissue lipids, but leads to oxidative stress in cells. This study investigated the effect of the dietary polyunsaturated FA ratio (PUFA n-6: n-3) and vitamin E (vE) level on DNA damage and morphological changes in the gut epithelium of chickens. One-day-old female broiler chicks (n = 176) were divided into 4 ...

Practice can dramatically reduce dual-task interference, but typically does not eliminate interference entirely. Residual interference after practice is especially large with certain non-preferred modality pairings (e.g., auditory-manual and visual-vocal). Does this residual interference imply the existence of a persistent central-processing bottleneck? To address this question, we transferred ...

In this research, the controversial issue of whether the central bottleneck can be bypassed through task automatization was investigated. To examine this issue, participants received six single-task practice sessions with an auditory-vocal task (low vs. high pitch). We then assessed dual-task performance using the analytically tractable psychological refractory period (PRP) paradigm, in which t...

The authors examined the role of online order control in the psychological refractory period (PRP) paradigm. In the first 2 experiments, participants switched between color-letter and letter-color orders so that subtask order was isolated as the only element being switched. The results indicated that order switching impaired the 2 PRP responses and modulated the PRP effect. Importantly, these e...

The divergent predictions of 2 models of dual-task performance are investigated. The central bottleneck and central capacity sharing models argue that a central stage of information processing is capacity limited, whereas stages before and after are capacity free. The models disagree about the nature of this central capacity limitation. The central bottleneck model claims that central processin...