Ana Helena Dias Francesconi

Feeding strategies to design the fatty acid profile of sheep milk and cheese

The majority of sheep milk produced in the world is transformed into cheese. Feeding is a major factor affecting the quality of sheep milk and, therefore, of sheep cheese. Because fat is the main compound of cheese, this review gives an update on the effects of feeding and nutrition on milk fat content and deeply discusses feeding strategies aimed at increasing the levels of healthy fatty acids (FA), such as conjugated linoleic acid and omega-3 FA, in milk and cheese in the human diet. In addition, the use of alternative feed resources such as by-products, aromatic plants, and phenolic compounds in the sheep diet and their effects on milk and cheese FA composition are also discussed. Among feeding strategies, grazing and the use of supplements rich in oils seem to be the best and the cheapest strategies to improve the nutritional value of the fatty acid profile in sheep cheese.

Myrtle (Myrtus communis L.) as a New Aromatic Crop: Cultivar Selection

SUMMARY Myrtus communis L. (Myrtaceae) is a typical shrub of the Mediterranean maquis which grows spontaneously in Sardinia. It is used in the drug, perfume and food industries. Intensive myrtle cultivation systems should be developed, in order to assure both a constant supply of good quality material for the liqueur industry and the preservation of natural myrtle populations. Cultivar selection is essential for the successful cultivation of this new aromatic crop and has been the main goal of our research. The main morphological and phenological characters of 16 cultivars selected for fruit and biomass production are presented here.

Models for estimating feed intake in small ruminants

This review deals with the most relevant limits and developments of the modeling of intake of sheep and goats reared intensively and extensively. Because small ruminants are normally fed ad libitum, voluntary feed intake is crucial in feeding tactics and strategies aimed at optimal animal production. The effects of genetic, neuroendocrine, hormonal, feed and environmental factors on voluntary feed intake were discussed. Then, several mathematical models to estimate dry matter intake (DMI) were examined, with emphasis on empirical models for sheep and goats in intensive farm systems or in extensive areas under pasture or rangeland conditions. A sensitivity analysis of four models of prediction of DMI in housed lactating dairy sheep and meat sheep breeds was also presented. This work evidenced a large variability in the approaches used and in the variables considered for housed sheep and goats. Regarding the estimation of feed intake for grazing sheep and browsing goats, the accuracy of estimates based on empirical models developed so far is very low when applied out of the boundaries of the studied system. Feeding experiments indoors and outdoors remain fundamental for a better modeling and understanding of the interactions between feeds and small ruminants. However, there is a need for biological and theoretical frameworks in which these experiments should be carried out, so that appropriate empirical or mechanistic equations to predict DMI could be developed.

Excretion of Aflatoxin M1 in milk of goats fed diet contaminated by Aflatoxin B1

Abstract An experiment was carried out to study the excretion of aflatoxin M1(AFM1) in milk of three goats fed a single dose (0.8mg/head) of pure aflatoxin B1 (AFB1). The values of AFM1 concentration excreted in milk was highly variable among goats, even if the pattern of excretion over time was very similar among the three animals. AFM1 was first detected at the milking performed 1h after the AFB1 administration. The highest values of AFM1 concentration in milk were reached 3 and 6h after the AFB1 intake. The trend of clearance of AFM1 in milk over time was expressed by a decreasing exponential equation. AFM1 concentration was below the EU maximum allowed level (50 ng/L) in milk collected 36 h after the AFB1 administration.

Selection of Rosemary (Rosmarinus officinalis L.) Cultivars to Optimize Biomass Yield

SUMMARY Rosmarinus officinalis L. (Labiatae) is a typical shrub of the Mediterranean maquis. In spite of its multiple ornamental and aromatic uses, and the great interest in its cultivation, only a few cultivars or clones have been well characterized. Our breeding program has focused on optimizing biomass yield and improving the quality of cultivated rosemary. In a preliminary phase (1996–1997), 31 mother plants were identified and described in situ throughout Sardinia; spring-shoot samples were then evaluated in laboratory. In a second phase (1996–2000), cuttings of selected clones were planted in a repository at the Experimental Station of the University of Sassari, in central-western Sardinia. In this paper, morphological, biometric, qualitative and phenological characters of fifteen rosemary selections of the repository are reported. Selections tended to produce flowers, fruit and new shoots in various periods of the year. Selections showed a high variability for spring-shoot length, leaf length and width, essential oil content of leaves, and percentage of leaf weight in relation to total shoot fresh weight. Clones with higher leaf/wood ratio and higher essential oil content were considered more suitable for the optimization of biomass yield.

Sustainable ruminant production to help feed the planet

Abstract Ruminant production has been an essential part of human activities worldwide since ancient times. The expected increase in world population and per capita income, with an increase in the amount and prevalence of animal products in human diet, urbanisation, with a concentration of population in urban areas and an increase in losses in the supply chain, and the growing concern over the environmental impact of animal farming require a long-term global strategy for a more intensive and sustainable ruminant production. Therefore, solutions to increase the supply of high-quality products of ruminant origin, without harming human health, animal welfare, and environment, should consider the following interconnected issues discussed in this review: (a) effects of meat, milk and dairy products consumption on human health, focussing on the imbalance caused by their insufficient consumption, and the alleged increased incidence of certain diseases due to their consumption; (b) importance of the sustainable intensification of ruminant production systems (e.g. better feed conversion and higher production output per unit of input introduced into the farming system); (c) environmental impact of ruminant production; (d) improvement of animal performance by improving animal welfare; (e) adaptation of ruminants to climate change; (f) sustainable ruminant feeding (e.g. precision feeding techniques, optimisation of grazing systems, and use of unconventional feeds); (g) challenges posed by production intensification to animal breeding and conservation of animal biodiversity; and (h) strategies to increase ruminant production in developing countries, thus achieving food security in vast areas of the planet affected by fast growth of human population.

Some bibliometric indexes for members of the Scientific Association of Animal Production (ASPA)

Abstract This study calculated several bibliometric indexes to analyze the scientific output of 363 members of the Scientific Association of Animal Production (ASPA) in Italy, based on their publications listed by ISI-Thompson, Web of Science database (search period from 1989 until 2006). Five main research areas were considered: AGR/17 (Animal genetics and breeding), AGR/18 (Animal nutrition and feeding), AGR/19 (Animal husbandry), AGR/20 (Poultry, rabbits and fish production) and External researcher (Ere). Position groups were: FP (Full Professor), AP (Associate Professor), Re (Researcher), EReUni (scientists working temporarily at the University or professors of an area different from AGR/17-20), and EReInst (scientists working at other institutions). Each institution was classified according to three geographical areas of Italy: North, Centre and South. Main calculated bibliometric indexes were: Ni = total number of papers published by member i over yi years; yi = number of years publishing of member i; Ci. = total number of citations of member i; IFpersonal. = Ci./Ni, Personal Impact factor of member i; Total IFjournal. = Sum of impact factor reported by the ISI-Thompson database of the journal in which a paper of member i was published (Journal Citation Reports Science Edition, 2004); Mean IFjournal. = Mean impact factor of all papers published in journals having a recognized IFjournal. by the ISI-Thompson database for member i; h = number of papers with at least h citations; m = h/y, i.e. average increase of h over the yi years publishing; and a = Ci./h2. Among the studied bibliometric indexes, Ni, Ci., Total IFjournal. and h are reliable, while IFpersonal. and Mean IFjournal. are not, to evaluate the scientific career of Animal Scientists in Italy. FP and members of AGR/17 tend to show the highest values of bibliometric indexes. Most ASPA members work in the North of Italy, which shows the highest median and highest percentage of scientists with maximum values for most bibliometric parameters. The scientific system of Animal Science in Italy has a fairly good degree of internationalization, but greater efforts should be made to increase the productivity and impact of Animal Scientists.

Estimation of nitrogen volatilisation in the bedded-pack of dairy cow barns.

Abstract The objective of the study was to measure N volatilisation (NVOL) from bedded-pack dairy cow barns. Feed intake, milk production, bedding material used and meteorological variables were monitored in 3 dairy farms near the town of Arborea (39°46’26” N, 08°34’53” E, 7 m a.s.l.) during one month for each season from summer 2007 to spring 2008. NVOL was measured in the interval between excretion and removal of bedded-packs from barn floors. NVOL was measured using the N (nitrogen) to P (phosphorus) ratio marker method, considering P as an internal non-volatile marker in milk and manure. Nitrogen and P excretion was estimated by nutrient balance as intake minus N and P excreted in milk. NVOL coefficient and bad-pack temperature were almost constant among seasons. The annual mean NVOL in bedded-pack barns was equal to 38.8% of excreted N. Accounting also for the NVOL that occurred in the concrete floor of the feeding and walking areas ofthe barns, NVOL was 40.7% of N excreted.

Evaluation of Spontaneous Oleander (Nerium oleander L.) as a Medicinal Plant

SUMMARY Nerium oleander L. (Apocynaceae) is a spontaneous plant widely diffused throughout the Mediterranean region. In Sardinia, it grows mainly near water flows, preferring humid and sunny environments. Oleander is used mainly as an ornamental. Since ancient times, both the toxicity and the medicinal properties of this species were well known. In fact, all plant parts are toxic if ingested and they can cause death by heart paralysis. This paper consists of a review on the medicinal characteristics of Nerium oleander and on its possible applications. In addition, a survey conducted on oleander types growing in Sardinia, aiming at evaluating their aptitude for medicinal uses, is discussed.

Microarray data analysis of gene expression levels in lactating cows treated with bovine somatotropin

Abstract Administration of bovine somatotropin (bST) to lactating cows results in an increase in milk production from 10 to 15%. While physiological mechanisms involved in bST administration are well known, there is limited knowledge about the mechanisms that regulate the bST action at genetic level. For this reason, a microarray experiment was conducted to identify differentially expressed genes when bST is given to milking cows. Sixteen high-density microarrays for cattle, each containing 18,263 gene spots, were used. RNA was extracted from the mammary tissue of four lactating Holstein cows, five and two days before, and one and six days after bST administration. A total of 1,251 and 1,167 differentially expressed genes were detected for mean and median expression intxsensities, respectively. Only the 115 genes which were identified by both mean and median intensities were taken into account. These genes were grouped into 8 clusters according to changes in expression through time points.