The role of veterinarian in the monitoring programs of mastitis control

Mastitis is the most common and the most expensive disease of dairy cows. It is followed by a large number of direct and indirect costs that burden the farms budget and lead to major economic and health losses. The veterinarian at the farm plays a key role in implementing a protocol of biosecurity measures, a protocol of control, therapy, and the suppression of clinical and subclinical mastitis. In order to successfully implement these measures, a good communication between a veterinarian and a farm staff who performs milking procedures is necessary in order to detect and treat all cases of mastitis in time

Efficiency of two protocols of resynchronization of estrus and ovulation in high-producing dairy cows at peak lactation

The reproductive efficiency of the cows was monitored after two resynchronization protocols: Ovsynch (OVS) and Double Ovsynch (DOS). The research initially included 70 HF cows who entered the first synchronization protocol - Presynch. Cows that did not conceive after the first synchronization were divided into two groups and introduced to two resynchronization protocols. In the first group of cows (n=35), the DOS protocol began with the application of GnRH on day 22 after the Presynch TAI (Timed Artificial Insemination), and seven days later pregnancy check-up was done and PGF2α was applied only to non-pregnant cows (n=23), which remained in the study. In the second group of cows, the OVS protocol started on day 32 after Presynch TAI only in non-pregnant animals (n=20). Progesterone (P4) concentration was determined at the time of application of GnRH1, PGF2α and GnRH2 in both groups of cows, and then 30 days after Resynch TAI, ultrasound pregnancy diagnosis was done. A higher percentage of pregnant cows were recorded in the OVS group compared to the DOS group (45% and 35%, respectively). The concentration of P4 in the serum of cows in the DOS group during the first measurement (GnRH1) was significantly higher than the value in cows that did not conceive (p<0.05), while in the third measurement (GnRH2) the average concentration of P4 in conceiving cows was significantly lower (p<0.001) compared to cows that did not coincive. The open days period was significantly longer in pregnant cows that were resynchronized using the DOS protocol compared to cows from the OVS protocol. In conclusion, the OVS protocol of estrus resynchronization in dairy cows proved to be more successful than the DOS protocol. However, considering the advantages the OVS, it is needed to determine which day of the sexual cycle is the best to start resynchronization

Hierarchical sequencing of online social graphs

In online communications, patterns of conduct of individual actors and use of emotions in the process can lead to a complex social graph exhibiting multilayered structure and mesoscopic communities. Using simplicial complexes representation of graphs, we investigate in-depth topology of online social network which is based on MySpace dialogs. The network exhibits original community structure. In addition, we simulate emotion spreading in this network that enables to identify two emotion-propagating layers. The analysis resulting in three structure vectors quantifies the graph's architecture at different topology levels. Notably, structures emerging through shared links, triangles and tetrahedral faces, frequently occur and range from tree-like to maximal 5-cliques and their respective complexes. On the other hand, the structures which spread only negative or only positive emotion messages appear to have much simpler topology consisting of links and triangles. Furthermore, we introduce the node's structure vector which represents the number of simplices at each topology level in which the node resides. The total number of such simplices determines what we define as the node's topological dimension. The presented results suggest that the node's topological dimension provides a suitable measure of the social capital which measures the agent's ability to act as a broker in compact communities, the so called Simmelian brokerage. We also generalize the results to a wider class of computer-generated networks. Investigating components of the node's vector over network layers reveals that same nodes develop different socio-emotional relations and that the influential nodes build social capital by combining their connections in different layers.Comment: 17 pages, 19 figure

Evaluation of 11 microsatellite loci for their use in paternity testing in Yugoslav Pied cattle (YU Simmental cattle)

Eleven microsatellite loci (TGLA227.BM2113, TGLA53, ETH10, SPS115, TGLA126, TGLA122, INRA023, ETH3, ETH225, BM1824) were evaluated for their use in paternity testing in the Yugoslav Pied cattle (YU Simmental cattle) population in Serbia. A total of 40 animals were tested. At the 11 tested loci, a total of 91 alleles were detected. The mean number of alleles per locus was 8.273. Polymorphism information content (PIC) values ranged from 0.58 to 0.88 with the mean value of 0.72. The most informative loci were: TGLAS3 (14 alleles, PIC = 0.88), TGLA227(11 alleles, PIC = 0.82), INRA023 (11 alleles, PIC = 0.86), BM2113 (9 alleles, PIC = 0.80). Combined power of discrimination (CPD) for the 11 microsatellite loci was 0.999. The results of the present study confirm that the analysed set of 11 microsatellite markers recommended by ISAG is suitable for paternity testing in Yugoslav Pied cattle in Serbia

Istraživanje polimorfizma gena za κ-kazein i beta-laktoglobulin u buše i holštajnfrizijske pasmine mliječnih krava u Srbiji

The aim of this study was to determine the distribution of κ-casein (κ-CN) and β-lactoglobulin (β-Lg) genotypes in the autochtonous (Busha) and dairy (Holstein-Friesian, HF) cattle breeds with PCR-RFLP (polymerase chain reaction - restriction fragment length polymorphism). For the amplification of κ-CN and β-Lg gene fragments specific primers were used. After digestion with specific endonucleases genotypes were determined for both genes in 18 Busha and 19 HF cows. The results showed that κ-CN gene was represented with the AA genotype in 31.58 % HF cows, AB in 52.63 % cows, whilst the genotype BB was found in 15.79 % cows only. Among the examined Busha cattle 44.44 % cows had AA genotype and 55.56 % genotype AB for κ CN. As for β-Lg gene in HF breed, AA genotype was found in 26.31 % cows, AB in 63.16 % and BB in 10.53 % cows. In Busha cows the following genotypes were established for β-Lg gene: AA in 44.44 % cows and AB in 55.56 %, whilst BB genotype was not found. These results indicate that Busha cows had a higher presence of A allelic forms of both genes (k-CN and β-lactoglobulin) than HF cows.Cilj istraživanja bio je utvrditi raspodjelu genotipova kapa-kazeina (κ-CN) i beta-laktoglobulina (β-Lg) u autohtonih (buša) i mliječnih (holstein, HF) pasmina goveda primjenom PCR-RFLP. Za amplifikaciju κ-CN i β-Lg fragmenata gena korištene su specifične oligonukleotidne početnice. Nakon digestije posebnim endonukleazama (Hinf I i Hae III) genotipovi su određeni za oba gena u 18 buša i 19 HF krava. Rezultati su pokazali da je κ-CN gen utvrđen genotipom AA u 31,58 % HF krava, AB u 52,63 % krava, dok je genotip BB utvrđen u samo 15,79 % krava. Od krava pasmine buša 44,44 % je imalo AA genotip i 55,56 % genotip AB za κ-CN. Što se tiče β-Lg gena u HF pasmine, AA genotip pronađen je u 26,31 % krava, AB u 63,16 % i BB u 10,53 % krava. U krava pasmine buša sljedeći genotipovi su utvrđeni za β-Lg gen: AA u 44,44 % i AB u 55,56 % krava, dok BB genotip nije utvrđen. Ovi rezultati pokazuju da je u krava pasmine buša veća prisutnost A alelne forme za oba ispitivana gena (za k-CN i β-laktoglobulin) nego kod HF krava

Reproduktivni monitoring i praktična primena hormonskih protokola na farmi mlečnih krava

Plodnost mlečnih krava globalno opada. Ukupna efikasnost ot- krivanja estrusa kod mlečnih goveda u laktaciji je smanjena, jer je is- poljavanje znakova estrusa vrlo suptilno i često teško uočljivo od stra- ne farmera ili štalskog personala. Shodno tome, neotkrivanje estrusa, visok indeks osmenjavanja i dug servis period su glavni razlozi koji do- prinose slaboj reproduktivnoj efikasnosti. Iako je jalovost najčešći ra- zlog za isključivanje mlečnih krava iz dalje proizvodnje, procenat steo- nosti se može popraviti efikasnijim otkrivanjem estrusa, primenom hormonskih protokola koji imaju za cilj fiksno vreme osemenjavanja (engl. Timed-AI-TAI) ili fiksnim embriotransferom (engl. Timed-ET). Ovim protokolima se kontrolišu razvoj folikula i luteoliza, što kulminira sinhronom ovulacijom kod većine krava. Postoji nekoliko modifikacija za poboljšanje stope uspešne koncepcije u protokolima TAI, kao što je presinhronizacija sa 2 doze PGF2α u razmaku od 14 dana, uz za- počinjanje OvSynch protokola 12. dana posle druge aplikacije PGF2α i drugi. Programi hormonske sinhronizacije i fiksnog osemenjavanja, osiguravaju pravovremenu aplikaciju semena, uz obavezan rani ultra- zvučni pregled na steonost (30-32 dana post inseminationem) kako bi se identifikovale neplodne krave i brzo nakon toga ponovo resinhroni- zovale i/ili osemenile. Ovaj rad ima za cilj da prikaže značaj pravilnog vođenja reproduktivne evidencije, da definiše najznačajnije reproduk- tivne parametre i objasni njihovu praktičnu primenu u izračunavanju realnih troškova farme. Takođe, u njemu se objašnjava kako se ultra- zvučnim pregledom plotkinja i utvrđivanjem njihovog trenutnog repro- duktivnog statusa definišu adekvatni hormonski protokoli u cilju sin- hronizacije estrusa i ovulacije

Persistent homology of complex networks

Long-lived topological features are distinguished from short-lived ones (considered as topological noise) in simplicial complexes constructed from complex networks. A new topological invariant, persistent homology, is determined and presented as a parameterized version of a Betti number. Complex networks with distinct degree distributions exhibit distinct persistent topological features. Persistent topological attributes, shown to be related to the robust quality of networks, also reflect the deficiency in certain connectivity properties of networks. Random networks, networks with exponential connectivity distribution and scale-free networks were considered for homological persistency analysis

The Effects of Antioxidants Provided with Feed on Certain Quality Parameters of Bull Semen under Heat Stress Conditions

The aim of the current research was to assess the effects of the feed additive made of lyophilised melon juice (source of superoxide dismutase, SOD) and inactivated live Saccharomyces cerevisiae (strain R397) cells added to the feed via the product containing high levels of organically bound selenium (source of selenium-dependant glutathione peroxidase, Se-GPx) on the semen quality of bulls in heat stress conditions. The 15 bulls chosen for the experiment were assigned to three equal groups (control-group C; treated group M, given the source of SOD; and group A, treated with the source of Se-GPx). The research was conducted in summer. The activities of SOD and Se-GPx in seminal plasma were determined spectrophotometrically. Computer-assisted semen analysis was done to determine the sperm counts, motility and velocity. The temperature and humidity were recorded with a digital data logger. The average SOD activity in the control bulls was significantly lower than in M (p0.05). In all of the three groups with the increase in THI there was an increase in GPx activity (p>0.05). It can be concluded that in all of the three groups of bulls there was an increase in the activity of both enzymes in the seminal plasma, but the increase was significantly lower in the control. Thus, the antioxidative capacity of the seminal plasma of untreated bulls was proven to be lower in comparison with those of the treated animals

Analysis of lactoferin gene polymophism and its association to milk quality and mammary gland health in Holstein-Friesian cows

Lactoferrin (LTF) is a glycoprotein, a member of transferrin gene family which plays an important role in immune mechanisms in the mammary glands of cows. The amount of lactoferrin increases during inflammatory processes and viral infections. The aim of this investigation was to monitor the distribution of lactoferrin gene genotypes and its connection to milk quality and the occurrence of mammary gland diseases in 46 Holstein-Freisian cows of different age (2-7 years) on a farm near Belgrade. DNA was isolated from blood samples, and the polymorphism of lactoferrin gene was deterimined by PCR-RFLP method using the restriction enzyme Eco RI. We found two alelic forms of this gene in cows included in these experiments (A and B) and two genotypes (AA and AB) in a ratio 71.7% to 28.3%. The genotype BB was not found in this sample. In order to determine the degree of differences between genotypes we used discriminant analysis which has shown that there is a statistically significant difference between genotypes AA and with respect to productive parameters. When analyzed separately, the only parameter which differed significantly (p=0.021) between two genotypes was total milk production. Individuals with observed genotypes are most similar for the amount of milk fat (p=0.271). There is no statistically significant difference in the number of somatic cells in milk samples between the examined genotypes. [Projekat Ministarstva nauke Republike Srbije, br. III46002