Provision of a protein-rich supplement for grazing suckling female beef calves to improve productive performance and metabolic response.

OBJECTIVE: This study was conducted to evaluate the effects of the provision of a protein-rich supplement on productive performance, and metabolic profile on grazing suckling female beef calves in tropical conditions during 150 d of experimentation. METHODS: Fifty-six Nellore suckling female calves, and their respective dams were distributed in a completely randomised design and made to undergo two treatments as follows: UNS (without supplementation), and SUP (supplementation with 5 g/kg body weight [BW] of a protein supplement). Throughout the experiment, animal performance and metabolic profile were evaluated. Also, ureagenesis and gluconeogenesis were assessed for gene expression. RESULTS: SUP female calves showed a higher voluntary intake (p≤0.03) of the diet components evaluated, digestibility of organic matter (p≤0.02) and microbial nitrogen production (MICN; p≤0.02) compared to UNS female calves. In its turn, serum urea nitrogen (p≤0.01) and insulin-like growth factor-1 (p≤0.03) levels and ureagenesis (p≤0.04) increased in SUP female calves compared to UNS female calves. Blood glucose and triglyceride levels were not affected by supplementation. The average daily gain (ADG) from SUP female calves was higher (p≤0.02) compared with UNS female calves. However, supplementation did not affect the body measures of the animals. CONCLUSION: In summary, provision of a protein-rich supplement improves the intake and nutrients digestibility, ADG and final BW and increases metabolic indicators of the protein status in grazing suckling female beef calves in tropical conditions.

Omega-3 Polyunsaturated Fatty Acid Deficiency and Progressive Neuropathology in Psychiatric Disorders: A Review of Translational Evidence and Candidate Mechanisms.

Meta-analytic evidence indicates that mood and psychotic disorders are associated with both omega-3 polyunsaturated fatty acid (omega-3 PUFA) deficits and progressive regional gray and white matter pathology. Although the association between omega-3 PUFA insufficiency and progressive neuropathological processes remains speculative, evidence from translational research suggests that omega-3 PUFA insufficiency may represent a plausible and modifiable risk factor not only for enduring neurodevelopmental abnormalities in brain structure and function, but also for increased vulnerability to neurodegenerative processes. Recent evidence from human neuroimaging studies suggests that lower omega-3 PUFA intake/status is associated with accelerated gray matter atrophy in healthy middle-aged and elderly adults, particularly in brain regions consistently implicated in mood and psychotic disorders, including the amygdala, anterior cingulate, hippocampus, prefrontal cortex, and temporal cortex. Human neuroimaging evidence also suggests that both low omega-3 PUFA intake/status and psychiatric disorders are associated with reductions in white matter microstructural integrity and increased rates of white matter hyperintensities. Preliminary evidence suggests that increasing omega-3 PUFA status is protective against gray matter atrophy and deficits in white matter microstructural integrity in patients with mood and psychotic disorders. Plausible mechanisms mediating this relationship include elevated pro-inflammatory signaling, increased synaptic regression, and reductions in cerebral perfusion. Together these associations encourage additional neuroimaging research to directly investigate whether increasing omega-3 PUFA status can mitigate neuropathological processes in patients with, or at high risk for, psychiatric disorders.

Polyunsaturated fatty acids and recurrent mood disorders: Phenomenology, mechanisms, and clinical application.

A body of evidence has implicated dietary deficiency in omega-3 polyunsaturated fatty acids (n-3 PUFA), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in the pathophysiology and etiology of recurrent mood disorders including major depressive disorder (MDD) and bipolar disorder. Cross-national and cross-sectional evidence suggests that greater habitual intake of n-3 PUFA is associated with reduced risk for developing mood symptoms. Meta-analyses provide strong evidence that patients with mood disorders exhibit low blood n-3 PUFA levels which are associated with increased risk for the initial development of mood symptoms in response to inflammation. While the etiology of this n-3 PUFA deficit may be multifactorial, n-3 PUFA supplementation is sufficient to correct this deficit and may also have antidepressant effects. Rodent studies suggest that n-3 PUFA deficiency during perinatal development can recapitulate key neuropathological, neurochemical, and behavioral features associated with mood disorders. Clinical neuroimaging studies suggest that low n-3 PUFA biostatus is associated with abnormalities in cortical structure and function also observed in mood disorders. Collectively, these findings implicate dietary n-3 PUFA insufficiency, particularly during development, in the pathophysiology of mood dysregulation, and support implementation of routine screening for and treatment of n-3 PUFA deficiency in patients with mood disorders.

Docosahexaenoic acid biostatus is associated with event-related functional connectivity in cortical attention networks of typically developing children.

OBJECTIVE: Although extant preclinical evidence suggests that the long-chain omega-3 fatty acid docosahexaenoic acid (DHA) is important for neurodevelopment, little is known about its role in human cortical structural and functional maturation. In the present cross-sectional study, we investigated the relationship between DHA biostatus and functional connectivity in cortical attention networks of typically developing children. METHODS: Male children (aged 8-10 years, n = 36) were divided into 'low-DHA' (n = 18) and 'high-DHA' (n = 18) biostatus groups by a median split of erythrocyte DHA levels. Event-related functional connectivity during the performance of a sustained attention task (identical pairs continuous performance task (CPT-IP)) was conducted using functional magnetic resonance imaging. A voxelwise approach used the anterior cingulate cortex (ACC) as the seed-region. RESULTS: Erythrocyte DHA composition in the low-DHA group (2.6 ± 0.9%) was significantly lower than the high-DHA group (4.1 ± 1.1%, P ≤ 0.0001). Fish intake frequency was greater in the high-DHA group (P = 0.003) and was positively correlated with DHA levels among all subjects. The low-DHA group exhibited reduced functional connectivity between the ACC and the ventrolateral prefrontal cortex, insula, precuneus, superior parietal lobule, middle occipital gyrus, inferior temporal gyrus, and lingual gyrus compared with the high-DHA group (P < 0.05; corrected). The low-DHA group did not exhibit greater ACC functional connectivity with any region compared with the high-DHA group. On the CPT-IP task, the low-DHA group had slower reaction time (P = 0.03) which was inversely correlated with erythrocyte DHA among all subjects. DISCUSSION: These data suggest that low-DHA biostatus is associated with reduced event-related functional connectivity in cortical attention networks of typically developing children.