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The aim of this research is to propose equations to estimate body weight (BW) from body measures (BMs) in the Cornigliese sheep, an endangered breed reared in Italy for meat purpose. BW and BMs were submitted to correlation and multiple regression analyses. Two datasets were used: (i) 303 animals (178 females, 125 males, BW 4.00–117.80 kg), on which BW, height at withers (HW), chest circumference (ChC) and body length (BL) were measured; (ii) 156 animals (109 females, 47 males, BW 5.15–117.80 kg) out of 303 on which croup height (HCr), chest width (ChW), chest depth (ChD) and croup width (CrW) were also considered. On each dataset, two regression models were applied, one containing all variables (models 1 and 3, respectively, for datasets 1 and 2) and the other one comprising groups of variables, selected by means of the stepwise procedure (models 2 and 4, respectively, for datasets 1 and 2). BW resulted correlated with all BMs (from 0.852 for ChW to 0.950 for ChC; p <.001). Models 1 and 3 fitted the data better than models 2 and 4, both for all animals and for females and males separately. We concluded that BW could be predicted from BMs also in Cornigliese sheep breed. The best fits were obtained when the highest number of measures was included in the model (models 1 and 3). Nevertheless, models 2 and 4 could be used more easily in extensive sheep breeding than models 1 and 3, since they require less parameters. The estimation of body weight is important in a meat type sheep breed for choosing the optimal slaughter time. A reduction of work for farmer is positive, mainly in field conditions of extensive rearing, where scales are not easily available. Body weight could be predicted from body measures in Cornigliese sheep breed with good precision and accuracy. [ABSTRACT FROM AUTHOR]

• Development of physical-chemical parameters calculated by allometric function. • Many physical-chemical traits of meat develop differently in males and females. • PUFA deposition increases with BW, but more in males than in females. • The choice of the BW at slaughtering could have an impact on consumers' health. With the aim to assess the kind of development of meat colour, pH, chemical composition and fatty acids content, lean meat from a sample cut, taken in correspondence of the first 4 thoracic vertebrae from 164 animals of the Cornigliese sheep breed, was analysed. The animals (104 females, 60 males) were fed with the same nutritional plan; they were between 3.6 and 80.0 months old and their body weight (BW) was between 15.90 and 111.15 kg. Prior to slaughter, the BW was recorded after 12 h of fasting. Based on BW at slaughter, animals were assigned to one of four BW-classes, identified by means of percentiles distribution: 0-25th percentile, 15.90–50.70 kg BW (n. = 42); 25th-50th percentile, 50.71–63.22 kg BW (n. = 40); 50th-75th percentile, 63.23–75.50 kg BW (n. = 42); 75th-100th percentile, 75.51–111.15 kg BW (n. = 40). They were slaughtered during 11 sessions. Data were analysed by ANOVA with sex, BW-class, year of birth (2013–2016) and interaction between sex and BW-class as fixed factors and slaughter session as a covariate. The relative growth of physical-chemical parameters of meat on BW was then calculated by applying the nonlinear allometric equation (y = a x b). Proximate analysis revealed differences between males and females in protein and fat content at the highest BW-class, with males showing a higher protein and a lower fat content than females (P < 0.05). Meat pH was lower in males than in females until 60 kg BW (P < 0.05), then became higher, but differences were not significant (P > 0.05). Meat colour parameters were not affected by sex in the BW-classes 1 and 4 (P > 0.05), whereas in the middle phase of growth (from 50 to 75 kg BW) males showed higher values for yellowness and chroma, and from 50 to 63 kg BW, also for redness (P < 0.05). Sex related differences in fatty acids (FA) content were recorded in relation to BW-class; poly-unsaturated FA (PUFA) were higher in males than in females from 50 kg BW onward (P < 0.05). The study of allometric function revealed that females were or tended to be earlier than males (lower allometric coefficients) for all parameters, except for meat fat and lightness. Meat fat content increased faster compared to BW in females than in males (P < 0.05). Moisture, ash, pH and lightness showed negative common allometric coefficients, and must be considered as very early developing parameters. Females showed negative allometric coefficients for C10-C20 saturated FA (SFA), whereas males showed positive allometric coefficients for C10-C16 SFA, then negative coefficients. Allometric coefficients for PUFA showed significant differences between sexes, being females earlier than males (P < 0.01): PUFA deposition increased with BW, but more in males than in females. Our study showed that in Cornigliese sheep breed most of the physical-chemical parameters of meat develop differently in males and females. Due to the different deposition of PUFA in males and females in relation to BW, the optimisation of time of slaughter is suggested as it can impact the physical-chemical parameters of meat, and it might in turn affect consumers' health. [ABSTRACT FROM AUTHOR]

The aim of the research was to assess the type of development of carcass and non-carcass components and tissue partitioning in the Cornigliese sheep breed. The study involved 164 animals (104 females, 60 males) from one flock. The selection of those animals accounted for ages and weights differences. Fasted body weight (BW) was recorded before slaughtering. Four BW-classes were identified by means of percentiles distribution: 0–25th percentile, 15.90–50.70 kg BW; 25th–50th percentile, 50.71–63.22 kg BW; 50th–75th percentile, 63.23–75.50 kg BW; 75th–100th percentile, 75.51–111.15 kg BW. After slaughter, the carcasses were weighed, measured (carcass length, croup width, chest width, chest depth, thigh length) and sectioned (shoulder, neck, thigh, ribs, loin, and lean and fat trimmings). A samplecut from 1st to 4th thoracic vertebra was then separated into its tissue components (lean meat, fat, bone). Non-carcass components (skin + fleece, head, liver, heart, lungs + trachea) were weighed. The data were analyzed using a GLM procedure accounting for the following fixed effects: sex, BW-class, year of birth and the interaction between sex*BW-class and the covariate: day of slaughter. The relative growth of carcass and non-carcass components on BW was calculated by applying the nonlinear allometric function ( y = a x b ). We found high coefficients of variation (CVs) (from 39% to 77%) for the weight of carcass components and low CVs (from 8% to 22%) for carcass measures. Non-carcass parameters showed intermediate values of CVs (from 30% to 42%). Body weight-class had a significant effect (P < 0.05) on all parameters, except on lean/fat ratio and lean percentage of the sample cut. Significant mean differences between genders were observed in the lean/fat ratio. In particular, in the lowest BW-class, females scored higher than males, whereas, in the highest BW-class, we observed the opposite trend (P < 0.05). Carcass, loin, lean and fat trimmings grew faster than BW, regardless of the sex. In contrast, as far as the neck is concerned, significant differences between females and males were observed (P < 0.05). Among carcass measures, a late maturing rate was recorded for croup width (b = 0.5042) and, in this case, females tended to be earlier than males (P < 0.10). Among non-carcass parameters, only head and skin + fleece weights showed differences between sex groups, with males showing a later development than females (P < 0.05). Tissues (lean, fat, bone) in the sample cut developed with different speed: the earliest tissue was bone (b = −0.3191), followed by lean (b = 0.0768) and finallyby fat (b = 0.8394). Bone development was significantly (P < 0.05) sex related, with males showing a later growth than females. Sex differences in the sample cut composition were also associated to lean/fat, (lean + fat)/bone and lean/bone ratios. This study has shown the potential use of the Cornigliese sheep as a commercial breed for meat production, although significant interaction between sex and body weight was observed. For this reason, it is recommended to implement a breeding strategy to reduce the incidence of extreme fattening females and the high incidence of non-carcass component in males when they reach high BWs. [ABSTRACT FROM AUTHOR]

With the aim to find indirect parameters for meat production that potentially could be used for selective purposes in Cornigliese sheep breed, 368 animals were weighed and measured (16 linear measures) during two years in 4 flocks with pasture and open range management from spring to autumn and closed facilities during winter. An amount of 0.2–0.4 kg/head/day of the same concentrate was provided to growing lambs from weaning to slaughter and to lactating ewes. Thirteen morphologic indexes were then calculated from body weight (BW) and linear measures. Analysis of variance on the basis of general linear model procedure was conducted with sex, age-class, year of birth, flock, type of lambing and interaction of sex*age-class as fixed factors and individual as a random factor. The allometric function was applied to body measures and indexes in relation to BW. A positive allometry was recorded for croup width between the trochanters (CrW1: 0.381), at ileum (CrW2: 0.452) and at ischium (CrW3: 0.615), indicating that this region has the fastest growth in relation to BW. All other body measures showed isometry or negative allometry, indicating a slower development in relation to BW. The lowest common allometric coefficient was recorded for front shank circumference (FSC) (0.131) followed by head width (0.200). Among indexes, the lowest growth was recorded by dactyl-thoracic index, due to the slow development of FSC. Sex related differences in allometric coefficients were noted for height at withers and head length (P < 0.05), FSC and forehead width (P < 0.01) with males earlier than females, and for chest width, chest depth, CrW1 (P < 0.05), CrW3 and ear width (P < 0.01) with females earlier than males. In conclusion the study of the allometric function applied to body measures and indexes was able to assess the importance of the croup width, not only in females (functional to an early and easy lambing) but also in males (functional to meat production). [ABSTRACT FROM AUTHOR]

A total of 72 animals from Cornigliese sheep breed were reared under homogeneous conditions, with the aim to assess the effect of sex (males, females) and age-class (heavy lambs, adults) on carcass and meat parameters. A model with fixed effects of herd, sex, slaughtering session, age-class and interaction (sex*age-class) was used; for slaughter data, the carcass weight was used as a covariate. The age-class effect was significant for most of the carcass measurements, indicating a late development in animals. Also, slaughter performance was significantly affected by age-class, with higher values (p<0.05) of hot carcass yield shown by heavy lambs than by adults. Carcass compactness index was lower in heavy lambs than in adults (p<0.001), and the lowest value (0.283; p<0.05) appeared in female heavy lambs. The percentage of fat trimmings in carcass and the tissue composition of sample cut were influenced by a significant interaction between age-class and sex (p<0.05): in males the age-class never affected the tissue composition of sample cut, as in females the muscle and fat percentages increased with age while the bone percentage decreased. The fat content of loin meat increased with age in females (p<0.05) and decreased in males (p<0.05). The poly-unsaturated fatty acids (FA) content of loin meat was higher in males than in females (p<0.001), with saturated FA and mono-unsaturated FA revealing significant interactions between age-class and sex (p<0.05). In conclusion, future implementation of genetic selection, oriented towards the improvement of meat production characteristics that are potentially present in the breed, is important. [ABSTRACT FROM AUTHOR]

To preserve sheep biodiversity is an important issue as the most productive breeds are becoming dependent on intensive management and breeders are abandoning the traditional breeds. The Cornigliese sheep is a local breed from Parma Apennine. In the last centuries it was crossed with Merino and Bergamasca breeds. The aim of this work is to investigate the genetic variability in the Cornigliese breed using 27 microsatellite markers. A total of 144 individual blood samples were randomly collected from the following breeds: Cornigliese, Bergamasca, Appenninica and Spanish Merino. The Palmera breed was used as out-group. A total of 344 alleles were detected. The average expected heterozygosity ranged from a maximum of 0.77 in Appenninica to a minimum of 0.68 in Bergamasca. In general, Cornigliese showed heterozygosity estimates less than expected. The Reynolds weighted genetic distance among the breeds highlighted a clear cluster, including Cornigliese and Bergamasca. As expected, they appeared in close neighbourhood in the tree because of the historic crossbreeding practices between these two breeds. Results of STRUCTURE analyses show that the four studied breeds were discriminated into separate clusters, even if Cornigliese has some individual related to Bergamasca and Spanish Merino. This work confirmed the historical information about the origin of Cornigliese breed which reports gene flow among these breeds. The genetic parameters show a moderate value of inbreeding in Cornigliese and therefore this breed should be monitored due the low number of individuals that compose it. [ABSTRACT FROM AUTHOR]