First records of Gastrotricha from South Africa, with description of a new species of Halichaetonotus (Chaetonotida, Chaetonotidae)

During a survey of the biota of the St. Lucia Estuary in the iSimangaliso Wetland Park, South Africa, a number of Gastrotricha were found among samples of meiofauna. Fresh, marine sediment yielded several specimens belonging to a total of seven species. Of these, two are already known from other regions (i.e., Dactylopodola australiensis and Heteroxenotrichula squamosa), one is described as new to science (Halichaetonotussanctaeluciae sp. n.), while the remaining four (Pseudostomella sp., Halichaetonotus sp.1, Halichaetonotus sp. 2, Xenotrichula sp.) require further collections and analysis, in order to establish the extent of their affiliation to species already described. General appearance, shape of hydrofoil scale and the occurrenceof three long spines on the dorsal side make the new species most closely related to H. australis and H. marivagus. The key differences from these taxa and between Halichaetonotus sanctaeluciae sp. n. and H. aculifer are discussed

A survey on Cattle Performance Testing Centres in Italy

Performance test is the main selection tool for beef and dual purpose cattle, but it is used also in dairy cattle, despite the different aim of testing in this case. This study has aimed to obtain all available information about organisation and characteristic of performance test in Italy carried out in year 2006 by Italian Cattle Breeders Associations. The results of the survey here reported have the final aim of exploiting actual organization of selection processes carried out in Italy for beef, dual purpose and dairy cattle breeds through performance test. The survey has indicated different intensity of selection among Italian breeds, ranging from 2.45 to 3.13

GENETIC AND PRODUCTIVE CHARACTERIZATION OF THE BURLINA CATTLE BREED

The Burlina (BUR) is a local Italian cattle breed, its main feature is to be a small sized animal well adapted to live in difficult environment such as mountain areas. Nowadays only 350 cows are enrolled in the Italian Herd Book due to its substitution by more productive breeds. This study proposes a phenotypic and genetic characterization of the BUR breed in comparison with Holstein Friesian (HFR) and Brown Swiss (BSW). The comparison of productive traits showed lower production than HFR and BSW as well as longer productive life and more favourable reproductive traits in BUR animals. The genetic analyses, performed by microsatellites markers, showed the high level of heterozygosity and the genetic distinctiveness of BUR. These findings approve the feasibility of a conservation scheme and suggest the profitability of breeding BUR, especially in difficult environment where the low production can be compensated by longevity and the economic loss by the added value of its typical dairy production

Genetic relationship between body condition score, fertility, type and production traits in Brown Swiss dairy cows

This study aimed to investigate the relationship between body condition score (BCS), calving interval (CI), angularity (ANG), strength (FV) and milk yield (MY) on Brown Swiss cattle using data collected in the alpine provinces of Bolzano- Bozen and Trentino. The data set consisted of 28,538 test day records of BCS and MY from 3,282 Brown Swiss cows in lactation reared in 109 herds; production traits were merged with 13,796 repeated individual calving interval records and 38,711 type traits records. A multi-traits REML animal model was used to estimate (co)variance components, with repeated observations. Heritability estimates for BCS, FV and ANG was 18%, 18% and 27%, respectively, while estimates for CI was very low (2%). Genetic correlations between CI and BCS was -0.44; between BCS and ANG was - 0.64; between BCS and MY was -0.35; between ANG and CI was 0.12. In conclusion, the selection for MY and ANG negatively affect fertility and average condition score of Brown cows. BCS recorded during lactation could be proposed as a useful trait for indirect selection aimed to improve fertility of cows

GENETIC CHARACTERISATION OF ITALIAN CHICKEN BREEDS USING A PANEL OF TWENTY MICROSATELLITE MARKERS

Genetic relationships among four Veneto native breeds of chickens were studied on the basis of microsatellites polymorphisms. A total of 190 DNA samples (45 Robusta Lionata, 43 Robusta Maculata, 45 Ermellinata di Rovigo, 45 Pèpoi) and a commercial broiler line (12 Golden Comet) were genotyped at 20 microsatellite loci. The average number of alleles per locus was 5 and the expected heterozygosity resulted lower for the local breeds than for the commercial broiler line used as reference. The inbreeding coefficient showed a deficit of heterozygotes, highest for the Robusta Lionata breed. Nei’s standard genetic distances corrected for bias due to sampling of individuals (Da), based on allele frequencies, and Reynolds distances (DReynolds) were calculated among breeds. The Robusta Lionata and Robusta Maculata resulted very similar approving the same genetic origin. A Neighbor-Joining tree drawn from DReynolds distances clustered three groups, one including the Robusta Lionata and Robusta Maculata breeds, the second one formed by the Ermellinata di Rovigo and the Golden Comet commercial line and the third by the Pèpoi. The results showed the genetic differences occurring between the local chicken breeds

Effect of crossbreeding on milk yield traits and somatic cell score in dairy cattle

This study aimed to estimate trends of heterosis for milk yield traits and somatic cell score (SCS) in the Dutch dairy cattle. First lactation data on 305-d milk, fat, and protein yield, and on average 305-d SCS recorded on pure Holstein Friesian (HF), Dutch Friesian (DF), Mosa Reno Yssel (MRY), and F1 crossbreds (DFxHF and MRYxHF) were considered. According to cows' year of calving, productive records from animals calving from 1980 to 2004 were divided in five periods, while SCS records from animals calving from 1990 to 2004 were divided in four periods. Data were processed using analysis of variance (ANOVA) according to a linear model which included effects of herd, season of calving, age at calving, and the genotype by period of calving interaction effect. Moreover, a linear covariate of sire's estimated breeding value (EBV) for 305-d milk yield was added to the model for yield traits. Heterosis values for productive traits were positive but decreased over time. For 305-d milk yield these values changed from 7.5 to 3.0% in the DFxHF crossbreds, and from 9.0 to 1.0% in the MRYxHF crossbreds. Average heterosis for SCS (-1.2%) was small and negative with a favourable trend over years

GENETIC ASPECTS OF MILK COAGULATION PROPERTIES IN DAIRY CATTLE

Authors reviewed the genetic aspects of milk coagulation ability focusing on heritability and genetic correlation values and on the breed and milk protein loci effects on rennet coagulation time and curd firmness. The review discussed milk and cheese yield production all over the world concluding that the per capita retail demand for cheese will increase with a mean annual growth rate of 0.8%. Therefore, in the future, cheese production will continue to be one of the major livestock food products around the world. The development of new payment systems for milk considering the intrinsic value for cheese making ability, could be an important opportunity for select best individual within dairy cattle breeds and to preserve, among dairy cattle breeds, those with high milk coagulation properties. Often these genetic resources, beyond their genetic value, also exercise a positive influence on sustainability of milk production in fragile environments, such as mountain areas, preserving an important cultural value (history, traditions, arts, and literature)

genetic aspects of milk electrical conductivity in italian brown cattle

Electrical conductivity (EC) of milk is defined as an indicator of the udder health. The EC is a low cost and easy recordable information in dairy herds with automatic milking systems. The heritability of EC showed to be higher than somatic cell count and for this reason might be an useful trait for indirect selection for mastitis resistance. The heritability for EC in Italian Brown cattle was equal to 0.23. Therefore, EC could be useful not only for dairy cows management but also for selection of dairy cows. The high correlation between breeding values for SCC and EC is promising in order for improving mastitis resistance and functional ability of dairy cows

Relations between different objective milking speed recording systems

This study aimed to analyse the sources of variation of milking speed assessed through automatic computerised devices included in milking machines, to study the relationships between this trait and milking speed assessed through stopwatch and to develop statistical procedures useful for converting automatic device milking time into stopwatch milking time in order to obtain a fast, simple and cheap collection of milking time records for genetic evaluation purposes. A total of 571 records of stopwatch milking time (SMT), device milking time (DMT) and milk yield at milking were collected in 23 herds of the Trentino Alto Adige region in Italy equipped with two types of automatic milking devices. After log-transformation of SMT (lnSMT) and DMT (lnDMT) and a preliminary analysis of sources of variation of lnDMT, dataset was partitioned into two mutually exclusive subsets: a calibration one, used for statistical analysis, and a validation one, used as test set to validate the prediction models. This procedure was replicated 6 times in order to repeat the cross validation accordingly. Three conversion models have been compared, based on different combinations of the effects of lnDMT, milking device and herd within milking device on lnSMT. Solutions of the models have been applied for each replicate to the validation dataset for estimating lnSMT and the soundness of conversion equations have been evaluated considering the correlation between estimated and actual lnSMT and bias and precision of estimates. Milking time assessed through different procedures resulted in differences between methods for both mean and distribution, and these suggested the need of developing statistical procedures aimed to the conversion of DMT into SMT before their use in sire evaulation. The soundness of the models tended to slightly increase with the increase in the number of effects considered. The correlation between estimated and actual SMT was in the range of 0.80 to 0.86, the estimated bias was close to 0 for all models and the precision, i.e. the average standard deviation of the difference between estimated and actual SMT, in the range of 8-9% of the mean of actual SMT. In conclusion, conversion equations proposed for joining the two sources of information performed satisfactorily, giving rise to SMT accurate estimates, which were not distorted and fairly precise. The use of such equations can support the integration of automatically acquired milking time records into breeding schemes, which is advisable for increasing the number of sires progeny tested and the accuracy of breeding values estimated