THE ROLE OF SOME ADDITIVES IN ENHANCING FEED EFFICIENCY AND HEALTH IN MONOGASTRIC ANIMALS
Tesi di Dottorato
Data di Pubblicazione:
2015
Citazione:
THE ROLE OF SOME ADDITIVES IN ENHANCING FEED EFFICIENCY AND HEALTH IN MONOGASTRIC ANIMALS / M. Comi ; tutor: V. Bontempo; coordinatore: G. Savoini. DIPARTIMENTO DI SCIENZE VETERINARIE PER LA SALUTE, LA PRODUZIONE ANIMALE E LA SICUREZZA ALIMENTARE, 2015 Dec 18. 28. ciclo, Anno Accademico 2015. [10.13130/comi-marcello_phd2015-12-18].
Abstract:
The global demand for food from animal agriculture is anticipated to nearly double by 2050. The growth in white meat (pork and poultry) production in developing countries between 1989 and 1999 has been remarkable - more than double the growth of red meat (cattle, sheep and goats). Increased production can be achieved by a combination of expansion in animal numbers and increased productivity. Higher productivity is a compound of higher offtake rates (shorter production cycles by, for example, faster fattening), and higher carcass weight or milk or egg yields. The projections show that the increase in livestock numbers will remain significant, but less so than in the past. Higher carcass weights will play a more important role in beef production, while higher offtake rates (shorter production cycles) will be more important in pig and poultry meat production.
In order to increase health and feed efficiency in monogastric animals, four trials were carried out to evaluate the role of some additives used to increase health in post-weaning piglets and in poultry meat production.
The aim of first study was to evaluate the effects of nucleotides administration to post-weaning piglets on ileal proinflammatory interleukin gene expression. Thirty-six weanling piglets (28 d of age, 7.85 ± 0.25 kg L.W.) were used in 28 days study. Piglets were allotted to 2 homogeneous groups (C, T) and fed the basal diet supplemented with oral nucleotides (UMP 88.05%, GMP 5.51%, AMP 3.82%, CMP 1.94% and IMP 0.68%; 0.8 g/piglet/day in 2.1 ml water solution) or saline. On day 14 both experimental groups were challenged with 1x109 CFU/g E. coli 0149:F4(K88). Growth performance and faecal score were evaluated weekly, while blood samples for immunological serum parameters, Fe and Vitamin B12 serum content were collected on days 0, 13, 18 and 26. Proinflammatory IL1a, IL1b, IL6, IL10, and TNF, TLR2 and TLR4 gene expression in ileal Peyer patches were evaluated at slaughtering after individual tissue sample collection by RT-PCR and β-actin as housekeeping gene. Growth performances were not affected by dietary treatment, while faecal score was ameliorated in T piglets after one week on trial (P< 0.05). Haptoglobin serum content was decreased in treated pigs (P<0.01). Dietary treatment did not affect serum Fe content, while vitamin B12 level was higher in nucleotide-fed animals (P< 0.05). At slaughtering IL6, IL10, TNF, TLR2 and TLR4 gene expression were decreased in nucleotide-fed pigs (P< 0.01). By these findings, dietary nucleotides supplementation in post-weaning piglets can positively affect gut health status, ameliorating inflammatory response and digestibility of nutrients in microbial stress conditions.
Second study was carried out with the aim to investigate the antimicrobial potential of a polyphenol-rich olive extract in vitro and its effects on growth performance, caecum microbial population, slaughtering performance and meat quality. In vitro antimicrobial trials were performed on test cultures (E. coli ATCC 25922, L. monocytogenes ATCC 7644, S. Enteritidis ATCC 12592 and S. aureus ATCC 6833); the growth was assessed every 12 h for 48 h as optical density of broth cultures added with different concentrations of the product (0.1/0.5/1/5%) incubated at 20°C; an evident inhibition was observed with the increasing of the product concentration and a total inhibition was observed with the highest one. Considering these results, an in vivo trial was performed. A total of 720 female ROSS308 broiler chicks with day-old were allocated into 4 treatments with different dietary treatments (basal diet supplemented without (CTR) or with vitamin E (T1, 200 I.U. /kg for each dietary phase) or with Polyphenols olive extract (T2, 1g/kg and T3, 5 g/kg respectively in ea
Tipologia IRIS:
Tesi di dottorato
Keywords:
broilers; piglets; polyphenols; emulsifiers; nucleotides; gene expression
Elenco autori:
M. Comi
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