53 research outputs found

    α<sub>S1</sub>-casein genetic variants in Sarda goat breed

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    Sardinia plays an important role in Italian goat breeding; this is due not only to the high extent of its patrimony and production, but also to the fact that the main breed, the Sarda goat, represents an interesting biodiversity source. As regards the morphologic variability, marked differences between subjects reared in the coast and mountain areas were found (Macciotta et al., 2002). These differences are due to the genetic selection on the autochthonous patrimony, set up by breeders and based on coat colour, horn presence and/or on functional criteria (udder shape). The need to improve milk yields also induced various breeders, mainly in those areas with better pasture conditions, to crossbreed the Sarda goats with more productive breeds. The present situation (Pazzola et al., 2002) shows how in the East coastal region (Sarrabus, Ogliastra and Baronia) and in the central mountain areas of Sardinia (Barbagia), subjects with more rural traits are reared (smaller size, small ears, presence of horns, etc.); while in the South and West areas (Sulcis and Guspinese) the influence of the Maltese breed is more evident. Both the productive traits variability (Brandano et al., 1978), and the morphologic aspect, is of great interest. Genetic variability can influence the survival of a sector hindered by the opening of the markets and by the strong competitiveness of zootechnical areas technologically more advanced. According to this point of view, considering that casein fractions are closely related to milk technological characteristics (Grosclaude et al., 1994), and to its possible productive differentiation (Remeuf, 1993), a study on αS1-casein allelic frequency was carried out, related also to the breeding region. The aim of the study is to acquire useful information in order to suggest an appropriate utilization of milk, to detect possible new alleles and to test the correlation between casein phenotype and morphology of the animals

    Influence of body weight on reproductive activity in Sarda female lambs

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    One way to improve reproductive performance of ewes is through extending its lifetime productivity. Breeding ewe lambs is one method of improving the reproductive performance in the sheep. In order to produce an offspring when the ewe lamb is approximately 1 yr of age, the autumn-born ewe must obtain puberty before the autumn breeding season begins. Onset of puberty is determined by integration of both internal and external factors, which then enable the neuroendocrine or hormonal event occur (Shirley et al., 2001). Age, photoperiod and body weight are the principal factors influencing puberty. The age at onset of the reproductive activity in the sheep is different among the various breeds. In the Sarda lambs the age of the onset of puberty is about 7-8 months. However the animals that have this age don’t reach the puberty if photoperiod and body weight are not suitable. Both the female lambs born in October-November and in February reach puberty in the same subsequent autumn breeding season. This reproductive behaviour evidences that photoperiod plays an important role in the onset of puberty (Papachristoforou et al., 2000).The female lambs born in later spring uneasily reach puberty within the subsequent breeding season, although photoperiod is favourable. This retard in the onset of reproductive activity is due to the attainment of the body maturity only during subsequent long day period but they reach reproductive activity only during the autumn of the subsequent year (Foster et al., 1985). In fact, some authors suggested that besides photoperiod and age, attainment of the 60% of adult weight is essential for onset of puberty (Abecia et al., 2001). Indeed the undernourished animals delay puberty, in comparison to well nourished subjects (I’Anson et al., 1997). This behaviour is linked to the different LH pulse frequency: restricted diet lambs show one pulse per 4 hours, instead fed ad libitum subjects manifest four or five pulse per 4 hours (Ebling et al., 1990). The purpose of this investigation is to determine the onset of puberty and to research its linkage with body weight in Sarda female lambs during breeding season under natural condition

    Genotype at the MTNR1A locus and response to melatonin treatment in Sarda lambs

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    With the aim to evaluate the effect of melatonin treatment and melatonin receptor 1A (MTNR1A) genotype on advance of puberty, 423 Sarda lambs were chosen. On June 26th, they were divided into three groups, each of 141 animals (groups 0, 1, and 2), on the basis of live weight. On June 30th, animals in group 1 received a single implant (18 mg melatonin), while group 2 received two implants. Group 0 was untreated. Thirty-five days after treatment (August 4th), rams were introduced and after 40 days they were removed. From January 1st to February 10th lambing dates were recorded. Genomic DNA was extracted and subjected to PCR for the amplification of exon II and then digested with enzymes MnlI and RsaI and placed into +/+, +/−, or −/− group for MnlI and C/C, C/T, or T/T group for RsaI. Samples were cloned and sequenced. Data obtained were subjected to χ2 test in order to evaluate the difference in fertility among groups and the link between genotype and reproductive activity. Genotype +/+ and C/C showed the highest incidence. Treated groups showed a higher number of lambing at 10th February compared to control group (P&lt;0.04). Melatonin treatment results more efficient in +/+ genotype

    Reproductive activity in sheep with different lambing period treated with melatonin in April

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    The object was to evaluate the effect of melatonin treatment on the advance in April of the reproductive resumption in Sarda breed sheep with different lambing period. For the research two farms, located in North Sardinia between 39° and 40° N, were chosen. In each farm, 120 lactating ewes were selected: 30 lambed between October 20th and November 20th (group 1); 30 lambed between December 1st and 30th (group 2); 30 lambed between January 1st and 30th; 30 lambed between February 1st and 28th (group 4). In each farm, each group of 30 animals was divided into two subgroups of 15 animals (M and C). On April 1st, in each farm, the animals of the M subgroups were treated with a implant containing 18 mg melatonin. The subgroups C were kept as control. The lambing dates and the number of newborn lambs were recorded until 220 days after ram introduction. In treated animals greatest fertility (P<0.01) and lowest distance in days from male introduction to lambing (P<0.01) were recorded. The best reproductive performances were found in the group 1 and 2 compared to the other two groups (P<0.01).The present research shows that melatonin treatment should be made 3 or 4 months after lambing, in order to obtain optimal results

    Characterization of the SREBP-1 Gene Polymorphisms and Milk Traits in Dairy Sheep

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    The SREBP genes (Sterol Regulatory Element-Binding Proteins) are involved in the milk fat synthesis. In dairy cows some polymorphisms at the SREBP-1 gene sequence have been related with milk fat content. The aim of this study was to characterize the entire coding regions of the SREBP-1 gene in Sarda sheep breed, in order to highlight any polymorphisms and their association with milk traits. Four-hundred adult and lactating Sarda ewes were selected. Individual milk yield was recorded monthly from Day 30 to Day 150 of lactation, and fat and protein concentration were analysed. A blood sample from each ewe was taken for DNA extraction; thus, all the 19 coding exons of the SREBP-1 gene were amplified by polymerase chain reaction (PCR). Single-strand conformation polymorphism analysis (SSCP) and sequencing were used to scan mutations. Results provide, for the first time, the entire coding DNA sequence (CDS) of the SREBP-1 gene in sheep, and by sequences analysis 8 polymorphisms have been detected. The statistical analysis exhibited no relationship between polymorphisms and milk traits. The low SREBP-1 gene diversity that emerged from the present study, may be linked to the important role of this gene in the mechanism of milk fat synthesis or to the severe genetic selection performed in the Sarda sheep. However, it would be necessary to extend the study, including other breeds and other genes, in order to expanding the knowledge about the process of milk fat synthesis in dairy sheep

    How future surgery will benefit from SARS-COV-2-related measures: a SPIGC survey conveying the perspective of Italian surgeons

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    COVID-19 negatively affected surgical activity, but the potential benefits resulting from adopted measures remain unclear. The aim of this study was to evaluate the change in surgical activity and potential benefit from COVID-19 measures in perspective of Italian surgeons on behalf of SPIGC. A nationwide online survey on surgical practice before, during, and after COVID-19 pandemic was conducted in March-April 2022 (NCT:05323851). Effects of COVID-19 hospital-related measures on surgical patients' management and personal professional development across surgical specialties were explored. Data on demographics, pre-operative/peri-operative/post-operative management, and professional development were collected. Outcomes were matched with the corresponding volume. Four hundred and seventy-three respondents were included in final analysis across 14 surgical specialties. Since SARS-CoV-2 pandemic, application of telematic consultations (4.1% vs. 21.6%; p &lt; 0.0001) and diagnostic evaluations (16.4% vs. 42.2%; p &lt; 0.0001) increased. Elective surgical activities significantly reduced and surgeons opted more frequently for conservative management with a possible indication for elective (26.3% vs. 35.7%; p &lt; 0.0001) or urgent (20.4% vs. 38.5%; p &lt; 0.0001) surgery. All new COVID-related measures are perceived to be maintained in the future. Surgeons' personal education online increased from 12.6% (pre-COVID) to 86.6% (post-COVID; p &lt; 0.0001). Online educational activities are considered a beneficial effect from COVID pandemic (56.4%). COVID-19 had a great impact on surgical specialties, with significant reduction of operation volume. However, some forced changes turned out to be benefits. Isolation measures pushed the use of telemedicine and telemetric devices for outpatient practice and favored communication for educational purposes and surgeon-patient/family communication. From the Italian surgeons' perspective, COVID-related measures will continue to influence future surgical clinical practice

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

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    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

    Measurement of the charge asymmetry in top-quark pair production in the lepton-plus-jets final state in pp collision data at s=8TeV\sqrt{s}=8\,\mathrm TeV{} with the ATLAS detector

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    ATLAS Run 1 searches for direct pair production of third-generation squarks at the Large Hadron Collider

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    Measurement of the W boson polarisation in ttˉt\bar{t} events from pp collisions at s\sqrt{s} = 8 TeV in the lepton + jets channel with ATLAS

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