The 5xFAD transgenic mouse model widely used in Alzheimer’s disease (AD) research recapitulates many AD-related phenotypes with a relatively early onset and aggressive age-dependent progression. Besides developing amyloid peptide deposits alongside neuroinflammation by the age of 2 months, as well as exhibiting neuronal decline by the age of 4 months that intensifies by the age of 9 months, these mice manifest a broad spectrum of behavioural impairments. In this review, we present the extensive repertoire of behavioural dysfunctions in 5xFAD mice, organised into four categories: motor skills, sensory function, learning and memory abilities, and neuropsychiatric-like symptoms. The motor problems, associated with agility and reflex movements, as well as balance and coordination, and skeletal muscle function, typically arise by the time mice reach 9 months of age. The sensory function (such as taste, smell, hearing, and vision) starts to deteriorate when amyloid peptide buildups and neuroinflammation spread into related anatomical structures. The cognitive functions, encompassing learning and memory abilities, such as visual recognition, associative, spatial working, reference learning, and memory show signs of decline from 4 to 6 months of age. Concerning neuropsychiatric-like symptoms, comprising apathy, anxiety and depression, and the willingness for exploratory behaviour, it is believed that motivational changes emerge by approximately 6 months of age. Unfortunately, numerous studies from different laboratories are often contradictory on the conclusions drawn and the identification of onset age, making preclinical studies in rodent models not easily translatable to humans. This variability is likely due to a range of factors associated with animals themselves, housing and husbandry conditions, and experimental settings. In the forthcoming studies, greater clarity in experimental details when conducting behavioural testing in 5xFAD transgenic mice could minimise the inconsistencies and could ensure the reliability and the reproducibility of the results.

Sixty entire male pigs from 2 distinct genotypes (30 Alentejano purebred, an autochthonous fatty genotype, and 30 commercial crossbred pigs, a lean genotype) were used to investigate the effects of dietary CP reduction and low-Lys levels on growth performance, carcass traits, and meat quality. Pigs with 59.9 ± 2.0 kg BW were randomly assigned within each genotype to 1 of 3 diets [normal CP diet (control), reduced CP diet adjusted for Lys (RPDL), and reduced CP diet not adjusted for Lys (RPD)] as a 2 × 3 factorial arrangement of treatments with 10 individually fed pigs per treatment. Pigs were slaughtered at 93.4 ± 2.4 kg BW. The results showed that intramuscular fat (IMF) content of longissimus lumborum muscle was greater in Alentejano than crossbred pigs (5.0 vs. 2.4%). The RPDL had no effect on IMF content, ADG, backfat thickness, and loin weight in both genotypes. The RPD promoted the increase (P < 0.05) in IMF content in crossbred (∼50%) but not Alentejano pigs, which indicates that Lys restriction can mediate the effect of RPD. Within crossbred pigs, meat obtained from pigs fed RPD had an increased IMF content (+1.3%) and a tendency for greater sensory scores (tenderness, juiciness, flavor, and acceptability) than those fed the control. The IMF content was positively correlated to flavor in Alentejano genotype (P < 0.05) but not in crossbred pigs. Alentejano and crossbred pigs had a greater tendency to deposit 18:1c9 and SFA, respectively. Despite the contribution of fatty acid composition to flavor, its influence on pork acceptability was more noticeable in crossbred than Alentejano pigs. In conclusion, the increased IMF promoted by dietary CP reduction in lean but not in fatty pig genotypes during the growing-finishing period is likely due to Lys limitation, which seems to enhance eating quality of pork. Copyright © 2013. American Society of Animal Science .

Grape by-products are exceptional options for replacement of conventional and unsustainable feed sources, since large amounts are generated every year from the winery industry. However, the majority is wasted with severe environmental and economic consequences. The present review aimed to evaluate the effects of grape by-products on pig and poultry growth performance. The most recent literature was reviewed using ScienceDirect and PubMed databases and the results of a total of 16 and 38 papers for pigs and poultry, respectively, were assessed. Fewer studies are documented for pig, but the incorporation of grape by-products up to 9% feed led to an improvement in growth performance with an increase in average daily gain. Conversely, lower levels (<3% feed) are needed to achieve these results in poultry. The beneficial effects of grape by-products on animal performance are mainly due to their antioxidant, antimicrobial, and gut morphology modulator properties, but their high level of cell wall lignification and content of polyphenolic compounds (e.g., tannin) limits nutrient digestion and absorption by monogastric animals. The use of exogenous enzymes or mechanical/chemical processes can provide additional nutritional value to these products by improving nutrient bioavailability. Overall, the valorization of grape by-products is imperative to use them as feed alternatives and intestinal health promoters, thereby contributing to boost circular agricultural economy.