Alberto Sabbioni

Phylogeny, genetic relationships and population structure of five Italian local chicken breeds

Number and population size of local chicken breeds in Italy is considered to be critical. Molecular data can be used to provide reliable insight into the diversity of chicken breeds. The first aim of this study was to investigate the maternal genetic origin of five Italian local chicken breeds (Ancona, Livorno, Modenese, Romagnola and Valdarnese bianca) based on mitochondrial DNA (mtDNA) information. Secondly, the extent of the genetic diversity, population structure and the genetic relationships among these chicken populations, by using 27 microsatellite markers, were assessed. To achieve these targets, a 506 bp fragment of the D-loop region was sequenced in 50 chickens of the five breeds. Eighteen variable sites were observed which defined 12 haplotypes. They were assigned to three clades and two maternal lineages. Results indicated that 90% of the haplotypes are related to clade E, which has been described to originate from the Indian subcontinent. For the microsatellite analysis, 137 individual blood samples from the five Italian breeds were included. A total of 147 alleles were detected at 27 microsatellite loci. The five Italian breeds showed a slightly higher degree of inbreeding (FIS=0.08) than the commercial populations that served as reference. Structure analysis showed a separation of the Italian breeds from the reference populations. A further sub-clustering allowed discriminating among the five different Italian breeds. This research provides insight into population structure, relatedness and variability of the five studied breeds.

Boar semen bacterial contamination in Italy and antibiotic efficacy in a modified extender

The aims of the study were to identify microbial flora in boar semen under field conditions in northern Italy, to investigate antibiotic resistance and sensitivity of isolated bacteria, and to evaluate elimination of bacteria after storage in two types of extenders added with different antibiotics (amikacin vs gentamicin). A total of 60 boars were collected in 13 pig farms. Bacteriological and mycological investigations were performed immediately on raw semen samples, then at 48 and 120 h of storage on semen diluted randomly in a new short-term modified extender (ME-S) or in a commercial one (CRONOSTM). Bacterial contamination was found in 63% of raw semen samples and different bacterial species were isolated: E.coli, Serratia marcescens, Staphylococcus epidermidis and aureus, Proteus spp., Streptococcus spp. and Pseudomonas aeruginosa. E. coli was the most isolated contaminant (53%); Pseudomonas aeruginosa was found only in one semen sample. The analysis of variance of factors affecting contamination levels was significant for the farm of origin (P<0.05) and not significant for the breed. Antibiotic resistance of these bacteria was assessed using different antibiotics. Significant differences (P<0.05) between observed and expected frequencies of bacterial isolates resistant or not to the antibiotics contained in the extenders were found. At 48 h of storage a reduction of aerobic contamination was found after ME-S dilution by 85.3% and after CRONOSTM by 63.8%. This paper proved the presence of pathogenic bacteria in semen. We thus believe it is highly advisable to perform periodic microbiological screening of boar semen in the swine industry to avoid the use of low sperm quality.

Milk production and lactation curves of Bianca Val Padana and Italian Friesian dairy cows in relation to the management system

The aim of this study was to evaluate milk production and lactation curve parameters of Bianca Val Padana (BVP) and Italian Friesian (IF) cattle reared in the same herds in relation to different housing-feeding systems. Therefore, 8488 test-day records of 103 BVP and 367 IF cows from 7 herds were used; 2 herds had free stalls and total mixed ration feeding (FS-TMR group) and 5 had tie stalls and traditional feeding (TS-TF group). Data for milk production (kg), fat, protein, lactose production (kg) and content (%), and somatic cell score (SCS) were submitted to analysis by ANOVA, using a model with breed, housing-feeding type, test day, herd within housing-feeding type, season of calving, lactation number, class of days in milk, and two- and three-way interactions as fixed factors. A mixed model according to Wood’s equation in linear form was also performed. Interactions between breed and type of housing-feeding were always significant (P<0.05), except for milk fat percentage and SCS. Daily milk, fat, protein and lactose productions were lower in TS-TF compared to FS-TMR, but the reduction was significantly higher (P<0.05) in IF than in BVP. Protein percentage showed an opposite trend in the two breeds depending on the type of housing-feeding. The lactation curves were continuously decreasing for BVP in FS-TMR housing-feeding type. In TS-TF rearing conditions, BVP showed an earlier week at peak and a lower peak production than IF. In conclusion, BVP seems to be better adapted to TS-TF rearing conditions than IF.

Effect of Duroc genes proportion on growth performance and on carcass and meat quality characteristics in heavy pigs

Abstract By means of the application of covariance models, the linear effects of the proportion of Duroc genes were evaluated with respect to growth (from 6 to 170 kg live weight) and feed/gain ratios, as well as carcass (lean cuts, adipose cuts, linear measures, backfat thickness, loin area and lean percentage) and meat quality (L* a* b* colour, reflectance, electrical conductivity, pH) in 167 heavy pigs (87 castrated males, 80 females) from different crosses of Duroc(D), Large White (LW) and Landrace (L) breeds, from 25 to approximately 300 d of age. The pigs were weighed at 25, 105, 170, 235 d and at the end of the trial (298 ± 6 d of age), and were raised under the same conditions. The proportion of Duroc genes was 0% (LWxL; no. 33), 25% [(LWx(DxL); n. 31 and Lx(DxLW); n. 35)] and 50% [Dx(LWx(LWxL)); n. 68]. The increase in the proportion of Duroc genes negatively affected the live weight at the different ages (P<0.05), but the weight at slaughtering was not affected (P>0.10). In fact, during the final phase (from 120 to 170 kg l.w.) the effect of the Duroc breed on daily gain became positive (P=0.08), and the feed/gain ratios were significantly lower (P=0.02). The carcass composition was not significantly influenced by the increase in the proportion of Duroc genes, with the exception of a rise in the weight of neck (P<0.01) and flare fat (P=0.02) and a reduction of ham (P=0.09). Carcass length resulted lower as the proportion of Duroc genes increased (P<0.01); at 24 h from slaughtering, meat colour showed lower values for lightness (P=0.08), redness (P=0.02) and yellowness (P=0.03).

Effects of oral administration of caffeine on some physiological parameters and maternal behaviour of sows at farrowing

Caffeine has been demonstrated to have a protective effect on neonatal viability of piglets. In order to assess whether caffeine, administered to parturient sows, also affects maternal behaviour, respiratory rate, and dopamine, nitric oxide and serotonin plasma levels, 20 sows, with induced parturition, received orally 27 mg/kg of body weight of caffeine (T group; n=10) or not (NT group; n=10), on day 113 of gestation. Treatment did not affect the farrowing length. There were less stillborn piglets in T group than NT group (0.67 vs 2.44; P<0.05), whereas no differences in dead piglets at 24h from birth was observed. Caffeine did not affect physiological parameters of sows, as the behaviour score of sows laying on belly was reduced (P<0.05). In conclusion, although the present study was carried out with a limited number of sows, administration of caffeine to parturient sows has the potential for reducing the number of stillborn.

Monitoring blood plasma leptin and lactogenic hormones in pregnant sows

The mechanism of action of leptin in pregnant breeding sows, in which hyperphagia is managed through dietary strategies, is yet to be clarified. The aim of this study was to monitor leptin concentrations and their interactions with lactogenic hormones in Large White×Landrace breeding multiparous sows (n=15). All sows showed a normal body condition (mean body condition score: 2.96). Blood samples were collected the day after weaning the litters, at insemination, every 15 days up to day 45 of pregnancy and every 7 days from day 46 to farrowing. At delivery, the placenta was collected for the analysis of leptin and leptin receptor expressions. Plasma leptin levels increased from the end of mid gestation (day 72) and remained high until farrowing (P<0.05). As expected, plasma prolactin (PRL), low during most of pregnancy, increased during the 2 weeks before farrowing (P<0.05), whereas progesterone levels reached plateau at 30 days of gestation and decreased at farrowing (P<0.05). Cortisol levels peaked close to farrowing (P<0.05). Leptin was expressed in the placenta, where the receptor expression analysis showed the presence of the short form but not of the long form. A positive correlation was found between leptin and PRL concentrations during mid (r=0.430; P<0.001) and late (r=0.687; P<0.001) pregnancy, and with progesterone in early pregnancy (r=0.462; P<0.05). During late gestation, a positive correlation was observed between leptin and cortisol (r=0.585; P<0.001). Our results suggested that, in restrictively fed pregnant sows, the leptin levels increased from the end of mid pregnancy to delivery, confirming the presence of leptin resistance. We showed a correlation between leptin and lactogenic hormones during different stages of pregnancy in sows. Lactogenic hormones show pregnancy-specific changes in their secretion and all may become involved in modulating leptin signal.

Peripheral cytokine expression in Standardbred mares at different adiposity during the periparturient period

The aim of this study was to evaluate whether the peripheral cytokine expression could be affected by differences in fat thickness in healthy mares during the periparturient period (last weeks of pregnancy and first weeks of lactation). At the beginning of the 11th month of gestation, 18 mares with normal body condition score (BCS; 5) were divided into two groups with low (L; ≤12 mm; n = 12) and high (H; >12 mm; n = 6) fat thickness. Blood samples were collected every 10 days from the 11th month of gestation to 20 days post partum. Peripheral blood mononuclear cells were separated and tumour necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-1α (IL-1α), -1β (ILβ), -2 (IL-2) and -6 (IL-6) gene expressions were performed by using reverse transcriptase PCR. TNF-α and IFN-γ expressions were affected by fatness group, as the sampling period influenced the expression of all cytokines with the exception of IFN-γ. The interaction between fatness group and sampling period tended to be significant (P < 0.10) only for IL-1β, TNF-α and IL-2. In H group, compared with L group, IL-1β and IL-2 significantly (P < 0.05) increased at parturition. TNF-α peripheral expression increased from parturition to reach the peak at +10 days (P < 0.05) only in H group. In conclusion, in normal BCS periparturient mares, small body fat thickness variations influence the peripheral cytokine expression, showing a possible role for cytokines in parturition and lactation, events strongly linked to adipose tissue availability.

Reproductive parameters of “Nero di Parma” sows reared outdoor and indoor

Abstract The swine genetic type “Nero di Parma” has been obtained after a preservation programme of a local breed suitable for outdoor rearing systems in Parma province. Actually, 480 females and 35 males are registered by Italian Swine Breeders Association and are reared in 28 herds of Parma province. The study involved the analysis of the reproductive performance of 120 sows from 19 boars, born between 1999 and 2005, during 211 parities from 2002 to 2006. For each parity, the boar, the age of the sow, the length of the farrowing interval, and the litter size (number of born alive, stillborn and weaned piglets) were recorded. Two rearing systems of the farrowing sows (from the final phase of gestation to the end of lactation) were considered: indoor (sows closed off in individual stalls or farrowing cages) and outdoor (sows in individual huts inside the paddocks, with straw bedding); dry sows in both systems had access on pasture with forage and concentrate integration. Data concerning sows performance were analyzed by a GLM procedure with a mixed model containing, as fixed factors, the type of rearing system of farrowing sows (2 levels: indoor, outdoor), the parity (4 levels: 1, 2, 3, >3), the farrowing season (4 levels), 1st degree interactions and, as a random factor, the father (n=19). Data concerning litter size were analyzed with a mixed model containing, as fixed factors the type of rearing system of farrowing sows, the parity, the farrowing season and year (5 levels), the herd (n=20) nested within type of rearing system, 1st degree interactions and, as a random factor, the boar (n=30). In both models, the inbreeding coefficient of sows, calculated from pedigree analysis, was used as a covariate. Type of farrowing sows rearing system significantly affected (P<0.05) the age at parities and the length of farrowing intervals. Farrowing sows reared indoor showed lower age at parities (737 vs 834 d) and farrowing intervals (236 vs 269 d) than outdoor sows. Parity number and inbreeding coefficient significantly affected (P<0.001) age at parities but not farrowing intervals. Additive genetic effect was significant (P<0.001) for both traits. With reference to litter size, no significant effects (P>0.05) were shown by type of rearing system on number of born alive piglets (8.51 vs 7.21 for indoor and outdoor sows, respectively), as year (P<0.05), season*year interaction (P<0.05) and boar (P<0.001) significantly affected the number of stillborn; type of rearing system showed a highly significant effect (P<0.001) on the number of weaned piglets (6.57 vs 3.95 for indoor and outdoor sows, respectively). In conclusion, the sows from the genetic type “Nero di Parma” show actually a low reproductive performance, however in line with those reported for other autochthonous breeds. In addition, the traits are affected by a rearing system, in which the control by the breeder is moderate. Because genetic improvement of reproductive traits is rather difficult, it seems to be necessary an improvement of farm management.

Effect of sex and season of birth on Gompertz growth curve parameters in "Nero di Parma" pigs

Abstract The growth curves of “Nero di Parma” pigs were studied by applying the Gompertz equation to 1069 body weight (BW) records from 285 pigs (156 females, 129 castrated males) born in 11 outdoor and 5 indoor herds; pigs were fed commercial complete feeds offered ad libitum and, on a limited basis in the outdoor system, diets were integrated with pasture. The parameters of the Gompertz equation were compared with reference to sex and season of birth. Mature BW for castrated males (229.0 kg) was 3.5% greater than that for females (221.3 kg) (P<0.05), but growth rate was 7.6% lower (7.38*10-3 vs 7.99*10-3, respectively) (P<0.05) and age at maturity (205.7 vs 189.6 d, respectively) was 16.1 d greater (P<0.05). Summer and winter born pigs showed a lower mature BW (P<0.05) than those born in other seasons. Summer born pigs grew slower than those born in spring (9.57%), winter (9.58%) and autumn (21.47%) (P<0.05). Earlier maturing pigs were those born in autumn, followed by those born in winter, spring and summer, respectively. Regardless of sex and season of birth, pigs showed their maximum ADG (ADGmax) of 635 g/d at 82.6 kg BW. Castrated males have a lower ADGmax than females (622 vs 650 g/d) at a heavier weight (84.2 vs 81.4 kg). Autumn born pigs showed the highest ADGmax (695 g/d), reached at 84.9 kg BW. The growth performance of “Nero di Parma” pigs is greater than those reported for Italian domestic pig breeds. The significant effect of the studied environmental factors on the growth curve in this genetic type will make it possible to choose the best rearing conditions in relation to its usual weight at slaughter (>180 kg).

Application of different growth models to "Nero di Parma" pigs

Abstract The growth curves of 280 “Nero di Parma” pigs from birth to maturity were calculated by applying nine different models (regressions from 1st to 4th degree and nonlinear regressions following the Brody, Logistic, Janoschek, Bertalannfy and Gompertz models) to 1109 individual records of body weight (BW) from two different data sets. The goodness of fit of experimental data was calculated by means of Residual Variance, Akaike Information Criterion, Residual Standard Deviation and R 2. The best fit was obtained by Gompertz equation, as follows: BW(kg)= 240.2±2.4 * esp (-exp (-0.0069±0.0001*(age(d)–213.5±3.1))). Regardless to the model, all correlations between actual and estimated BW were highly significant (P<0.001): the highest correlation (0.980) was obtained by the application of the Gompertz equation. In conclusion the growth of “Nero di Parma” pigs can be well described by applying the Gompertz model to field data.