V. Dell'Orto

Comparative mammalian choline metabolism with emphasis on the high-yielding dairy cow.

The present review examines the importance of choline in dairy cow nutrition. Choline is an essential nutrient for mammals when excess methionine and folate are not available in the diet. The requirement for choline can be met by dietary choline and by transmethylation reactions. Two types of functions for choline are known: functions of choline per se; functions as a methyl donor. The two principal methyl donors in animal metabolism are betaine, a metabolite of choline, and S-adenosyl-methionine, a metabolite of methionine. Choline and methionine are interchangeable with regard to their methyl group-furnishing functions. In adult ruminants, choline is extensively degraded in the rumen; for this reason dietary choline contributes insignificantly to the choline body pool and methyl group metabolism is generally conservative with a relatively low rate of methyl catabolism and an elevated rate of de novo synthesis of methyl groups via the tetrahydrofolate system. In dairy ruminants, the dietary availability of choline is still low, but the output of methylated compounds in milk is high, and precursors from the tetrahydrofolate pathway are limiting, especially at the onset of lactation. Therefore choline may be a limiting nutrient for milk production in high-yielding dairy cows.

Effects of feeding calcium salts of long chain fatty acids on milk yield, milk composition and plasma parameters of lactating goats

Abstract Thirty-two goats were fed concentrates, one containing 6% calcium salts of fatty acids. Rations contained equal quantities of Ca and N. Fatty acid calcium salts significantly increased milk fat (from 3.4 ± 0.1 to 3.7 ± 0.2%), but the percentage of short and medium chain fatty acids (C4 to C14) in milk fat decreased (from 37.5 ± 1.0 to 32.2 ± 0.6%). The group fed fatty acid calcium salts had increases in plasma cholesterol (3.5 ± 0.2 vs. 4.3 ± 0.2 mmol/1), phospholipids (2.5 ± 0.1 vs. 2.9 ± 0.1 mmol/1) and gamma-glutamyltranspeptidase (28.9 ± 1.5 vs. 33.5 ± 2.3 U/1).

Sampling feed for mycotoxins: acquiring knowledge from food

Abstract The occurrence and control of mycotoxins in feed and food are items of great interest to researchers, producers, manufacturers and regulatory agencies. In order to implement knowledge of control measures for mycotoxins in the entire food production chain, coordinated inspection programmes aimed to check the presence and concentration of mycotoxins in feedingstuffs are recommended by the Commission of the European Communities. Reliability of measured levels of mycotoxins in feed and food is greatly affected by the collection of representative samples. Because of the heterogeneous distribution of mycotoxins, the variability associated with a mycotoxin test procedure usually depends heavily on the sampling plan. European legislation dealing with sampling plans for mycotoxins in foodstuffs has been recently revised. The aim of the following overview is to discuss the role of sampling in mycotoxin-contaminated feed by considering the evolution of legislation dealing with sampling plans for food. A sampling procedure is a multistage process and consists of three distinct phases: sampling, sample preparation and analysis. The variability associated with each step of a sampling procedure and the aspects related to feedstuffs, matrix/mycotoxin combination and level of contamination are discussed.

Evidence for false-positive results for Boldenone testing of veal urine due to faecal cross-contamination during sampling

European Directive 96/22/EC, which controls veterinary residues in animals, does not permit the presence of synthetic growth promoters in products of animal origin or in livestock. Boldenone is categorized in class A3 (growth promoters — steroids) and is thus a banned substance. Testing of veal urine for banned substances is part of the European Union statutory programme for animals going into the food chain. In relation to this monitoring, three studies were conducted to investigate the apparent presence of the banned growth promoter boldenone in veal urine, which was suspected as being caused by interference from faecal contamination of the sample. In the first study, urine samples were collected at different times (time 0 and after 30 min) using (1) a conventional zoonotechnical apron and (2) a technique designed specifically to avoid faecal contamination (‘kettle’). This resulted in samples that were, respectively, positive and negative for the presence of α-boldenone (α-BOL). In a second study, urine samples negative to α-BOL were collected from eight veal calves, but became positive after deliberate faecal contamination. In a third study, data obtained from the Italian RNP (Residual National Program) indicated that 18.1% of 3295 urine samples collected using the zootechnical apron were positive for α-BOL and 2.1% for β-boldenone (β-BOL), whilst of 902 samples collected using the kettle, β-BOL was not detected in any samples and only 0.2% were positive to α-BOL, in concentrations lower than 2 ng ml−1. These results further support the supposition that faecal contamination of the urine during sample collection can lead to false-positive results during boldenone analysis.

Effects of inclusion of selenium-enriched yeast in the diet of laying hens on performance, eggshell quality, and selenium tissue deposition

The aim of this study was to evaluate the bioavailability of ingested selenium (Se) yeast in laying hens and its effects on performance, eggshell quality, and tissue Se distribution. Forty-eight ISA brown laying hens were divided into 3 treatment groups: Group C, fed a basal diet containing 0.11 mg Se/kg of feed; Group SS, fed a basal diet plus 0.4 mg/kg of feed of Se from sodium selenite; and Group SY, fed a basal diet plus 0.4 mg/kg of feed of Se from selenium yeast. Feed intake, egg mass ratio, and production performance were not affected by Se supplementation, regardless of the Se source. Egg weight (+3.61% and +2.95%), eggshell weight (+4.26% and +5.38%), and eggshell surface (+2.43% and +1.96%) were higher (P<0.05) in SS and SY than C, whereas breaking strength was increased in SY (P<0.01). Breast muscle, liver and skin Se levels were higher in SY than in C, while kidney Se content was higher in SS hens. Eggs from SY had higher Se levels than SS. Blood metabolites were not affected in SS or SY groups than C. A higher Se level was detected in eggs and breast muscle of SY hens (P<0.05). Seleniumenriched eggs and edible tissues from organic Se sources in poultry diet could improve antioxidant status in humans and reduce possible Se deficiency-related diseases.

Implementation of the electronic nose for the identification of mycotoxins in durum wheat (Triticum durum)

The on-line evaluation of the quality of durum wheat (Triticum durum) represents, in terms of health and safety, one of the leading challenges of the milling industry. Knowledge of the content and distribution of mycotoxins on wheat kernel is very economically relevant and has great health implications due to its high impact on human health and on the safety of the use of decortication products in animal nutrition. The production of mycotoxins by particular mould strains is generally associated with the production of volatile substances such as alcohols, aldehydes, ketones and esters (Magan and Evans, 2000). On this basis we intended to develop the innovative method of the sensorial analysis (based on the use of an “electronic nose”), with the aim of evaluating its potential use as a rapid diagnostic test for determination of the levels of mycotoxin contamination in durum wheat.

A general review and survey of maternal behaviour in the rabbit

Abstract The literature on maternal behaviour of rabbits is reviewed with special emphasis on socialization, mating, nest building and parturition. The results of a survey of mating and maternal behaviour in rabbits are reported.

Expression of verocytotoxic Escherichia coli antigens in tobacco seeds and evaluation of gut immunity after oral administration in mouse model

Verocytotoxic Escherichia (E.) coli strains are responsible for swine oedema disease, which is an enterotoxaemia that causes economic losses in the pig industry. The production of a vaccine for oral administration in transgenic seeds could be an efficient system to stimulate local immunity. This study was conducted to transform tobacco plants for the seed-specific expression of antigenic proteins from a porcine verocytotoxic E. coli strain. Parameters related to an immunological response and possible adverse effects on the oral administration of obtained tobacco seeds were evaluated in a mouse model. Tobacco was transformed via Agrobacteium tumefaciens with chimeric constructs containing structural parts of the major subunit FedA of the F18 adhesive fimbriae and VT2e B-subunit genes under control of a seed specific GLOB promoter. We showed that the foreign Vt2e-B and F18 genes were stably accumulated in storage tissue by the immunostaining method. In addition, Balb-C mice receiving transgenic tobacco seeds via the oral route showed a significant increase in IgA-positive plasma cell presence in tunica propria when compared to the control group with no observed adverse effects. Our findings encourage future studies focusing on swine for evaluation of the protective effects of transformed tobacco seeds against E. coli infection.

Modulation of plasma antioxidant activity in weaned piglets by plant polyphenols

This study was conducted to evaluate the effect of plant polyphenols (PP) on antioxidant activity in weaned piglets. First, a uniform design, one optimising an experimental technique that can rationally arrange the concentrations of mixture components, was used to obtain the best PP mixture of apple, grape seed, green tea and olive leaf polyphenols based on in vitro antioxidant capacity and inhibitory action on bacterial growth. Second, the optimised PP mixture was tested in vivo with an efficacy trial on piglets. The optimal effects of the mix were observed in vitro when apple, grape seed, green tea, olive leaf polyphenols and a carrier (silicon dioxide) accounted for 16.5, 27.5, 30, 2.5 and 23.5%, respectively, of the mixture. Forty-eight weaned piglets were randomly allocated to two dietary treatments (6 replicates of 4 piglets each per treatment) and fed a control diet (CTR) or CTR supplemented with 0.1% of the optimised PP mixture. Dietary PP did not affect growth performance compared to the CTR group. Plasma total protein, urea nitrogen and lysozyme content were not affected by dietary treatment. No differences of E. coli or Clostridia counts in the faeces and caecum content between the CTR and PP groups were observed. A reduced malondialdehyde concentration in the PP group was observed on day 21 compared to the CTR group (P=0.02). In conclusion, the prepared PP mixture has the potential to improve plasma antioxidant activity.

Potential Application of Electronic Olfaction Systems in Feedstuffs Analysis and Animal Nutrition

Electronic Olfaction Systems (EOSs) based on a variety of gas-sensing technologies have been developed to simulate in a simplified manner animal olfactory sensing systems. EOSs have been successfully applied to many applications and fields, including food technology and agriculture. Less information is available for EOS applications in the feed technology and animal nutrition sectors. Volatile Organic Compounds (VOCs), which are derived from both forages and concentrate ingredients of farm animal rations, are considered and described in this review as olfactory markers for feedstock quality and safety evaluation. EOS applications to detect VOCs from feedstuffs (as analytical matrices) are described, and some future scenarios are hypothesised. Furthermore, some EOS applications in animal feeding behaviour and organoleptic feed assessment are also described.