O_2 solubility in Martian near-surface environments and implications for aerobic life

Due to the scarcity of O_2 in the modern Martian atmosphere, Mars has been assumed to be incapable of producing environments with sufficiently large concentrations of O_2 to support aerobic respiration. Here, we present a thermodynamic framework for the solubility of O2 in brines under Martian near-surface conditions. We find that modern Mars can support liquid environments with dissolved O_2 values ranging from ~2.5 × 10^(−6) mol m^(−3) to 2 mol m^(−3) across the planet, with particularly high concentrations in polar regions because of lower temperatures at higher latitudes promoting O_2 entry into brines. General circulation model simulations show that O_2 concentrations in near-surface environments vary both spatially and with time—the latter associated with secular changes in obliquity, or axial tilt. Even at the limits of the uncertainties, our findings suggest that there can be near-surface environments on Mars with sufficient O_2 available for aerobic microbes to breathe. Our findings may help to explain the formation of highly oxidized phases in Martian rocks observed with Mars rovers, and imply that opportunities for aerobic life may exist on modern Mars and on other planetary bodies with sources of O_2 independent of photosynthesis

Follow the Oxygen: Comparative Histories of Planetary Oxygenation and Opportunities for Aerobic Life

Aerobic respiration—the reduction of molecular oxygen (O_2) coupled to the oxidation of reduced compounds such as organic carbon, ferrous iron, reduced sulfur compounds, or molecular hydrogen while conserving energy to drive cellular processes—is the most widespread and bioenergetically favorable metabolism on Earth today. Aerobic respiration is essential for the development of complex multicellular life; thus the presence of abundant O_2 is an important metric for planetary habitability. O_2 on Earth is supplied by oxygenic photosynthesis, but it is becoming more widely understood that abiotic processes may supply meaningful amounts of O_2 on other worlds. The modern atmosphere and rock record of Mars suggest a history of relatively high O2 as a result of photochemical processes, potentially overlapping with the range of O_2 concentrations used by biology. Europa may have accumulated high O_2 concentrations in its subsurface ocean due to the radiolysis of water ice at its surface. Recent modeling efforts suggest that coexisting water and O2 may be common on exoplanets, with confirmation from measurements of exoplanet atmospheres potentially coming soon. In all these cases, O_2 accumulates through abiotic processes—independent of water-oxidizing photosynthesis. We hypothesize that abiogenic O_2 may enhance the habitability of some planetary environments, allowing highly energetic aerobic respiration and potentially even the development of complex multicellular life which depends on it, without the need to first evolve oxygenic photosynthesis. This hypothesis is testable with further exploration and life-detection efforts on O_2-rich worlds such as Mars and Europa, and comparison to O_2-poor worlds such as Enceladus. This hypothesis further suggests a new dimension to planetary habitability: “Follow the Oxygen,” in which environments with opportunities for energy-rich metabolisms such as aerobic respiration are preferentially targeted for investigation and life detection

Milk with functional food properties

This paper presents the results reflected on obtaining the milk enriched with omega-3 fatty acids. As source of omega-3 fatty acids, product of French company Vitalac called "TradiLin", was used. Trial was carried out on 20 trials (T) and 20 control (C) cows of Simmental breed and it lasted 80 days. Average content of omega-3 in trial and control group was 0.586 and 0.284 g/100g of extracted fat (P≤0.01), whereas content of omega-6 in same order of treatments was 3.141 and 3.011 g/100g of extracted fat (P≤0.05). Ratio omega-6/omega-3 fatty acids of 10.602 (control) was declined to 5.360 (trial), which is considered to be desirable from the aspect of nutrition with milk as functional food. Also, in other milk final product called "mladi kajmak", obtained by taking off milk fat from the surface of heat treated and cooled milk, content of omega-3 in trial and control group showed the same trend, 0.76 and 0.41 g/100g of extracted fat (P≤0.01), whereas content of omega-6 were 3.90 and 3.79 g/100g of extracted fat (P≤0.05). Ratio omega-6/omega-3 in control group was reduced of 9.24 to 5.10, which are considered to be extremely favourable. Chemical constituents of milk, somatic cell count as well as total plate count showed no differences between groups (P>0.05). Also, investigated treatment had no effect on changes in biochemical blood parameters

Ispitivanje uticaja mase pre klanja na rezultate vrednosti randmana klanja muških tovnih junadi domaće Simenatalske rase

For the purpose of investigation of factors important for slaughter yield results, a trial with three groups of young cattle of Domestic Simmental breed of different body masses was carried out. Young cattle in the first group (G1) (n=6) had average body mass of 509,00 kg (475-525), in the second group (G2) of young cattle (n=7) average body mass of 554,29 kg (530 - 575) was recorded and in the third group of young cattle (G3) (n=8) 591,13kg (580-615). Subsequent to slaughtering warm carcass sides were measured individually, with and without kidney fat, mass of internal organs was measured (kidneys, liver, lungs, heart, spleen) and mass of other secondary slaughter products (head, tongue, tail, muscle part of diaphragm). After cooling carcass sides were cut into main parts. Based on obtained results of research it was established that male cattle of group (G2) of Domestic Simmental breed of average body mass of 554,29 kg have realized higher slaughter yield compared to groups G1 and G3, whereas the share of kidney fat was the same in all three groups of young cattle. Share of mass of internal organs was the lowest in young cattle of group G2 (2,47%) whereas in other two groups it was the same. Share of mass of other secondary slaughter products (head, tongue, tail, muscle part of diaphragm) in all three groups of young cattle was the same. Share of mass of round (I category part of the carcass) was the highest in young cattle of group G3 (29,86), and statistically significantly (P (lt) 0.05) lower in group G1 (28,39). Share of carcass parts of II category (loin, back, shoulder) was the lowest in young cattle of group G3 (23,655), and of carcass parts of category III (second thigh, second fore thigh, neck, breasts, ribs, belly) in young cattle of group G2 (44,45%).U cilju ispitivanja faktora značajnih za rezultate vrednosti randmana klanja, izveden je ogled sa tri grupe junadi domaće simentalske rase različite telesne mase. Prva grupa (G1) junadi (n=6) bila je prosečne mase 509,00 kg (475-525), druga grupa (G2) junadi (n=7) bila je prosečne mase 554,29 kg (530-575) i treća grupa (G3) junadi (n=8) bila je prosečne mase 591,13 kg (580-615). Posle klanja izvršeno je pojedinačno merenje toplih polutki sa i bez bubrežnog loja, merenje mase unutrašnjih organa (bubrezi, jetra, pluća, srce, slezina) i merenje mase ostalih pratećih proizvoda klanja (glava, jezik, rep, mišićni deo dijafragme). Posle hlađenja polutke su rasečene u osnovne delove. Na osnovu dobijenih rezultata istraživanja utvrđeno je da su muška junad druge grupe (G2) domaće simentalske rase prosečne mase 554,29 kg, ostvarila veći randman u poređenju sa grupama G1 i G3, dok je učešće bubrežnog loja bilo isto kod sve tri grupe junadi. Učešće mase unutrašnjih organa najmanje je kod junadi grupe G2 (2,47%) dok je kod je kod ostale dve grupe bilo isto. Učešće mase ostalih pratećih proizvoda klanja (glava, jezik, rep, mišićni deo dijafragme) u sve tri grupe junadi je isto. Učešće mase buta (deo trupa I kategorije) najveće je u junadi grupe G3 (29,86), a statistički značajno (P (lt) 0.05) manji u grupe G1 (28,39).Udeo delova trupa II kategorije (slabine, leđa, plećka) najmanji je u junadi grupe G3 (23,655), a delova trupa III kategorije (potkolenica, podlaktica, vrat, grudi, rebra, potrbušina) u junadi grupe G2 (44,45%)

Proizvodnja junećeg mesa sa svojstvima funkcionalne hrane

In this study the effects of 'Tradi-Lin' as a source of omega-3 fatty acids (FA) in diets for fattening cattle were presented. 'Tradi-Lin' produced from flax seed had 58% omega-3 and 15% omega-6 fatty acids of total polyunsaturated fatty acids (PUFA). Trial was carried out on three groups of finishing beef cattle (C, T1 and T2) with 15 heads in each and was lasted 60 days. The diets used based on maize silage and concentrate mixture. Cattle received 0, 300 and 700 g of 'Tradi-Lin' per day, respectively. At the end of trial heads were slaughtered and major parameters of the chemical composition and meat quality were determined. The results indicated that were no differences in saturated (50.85; 50.21; 50.34%) and unsaturated (49.15; 49.79; 49.66%) FA between treatments in intramuscular fat of the m. longissimus dorsi but 'Tradi-Lin' influenced the changes in structure of intramuscular fat and increased PUFA from 4.91 (C) to 5.54 (T1) and 7.31% (T2) ( P (lt) 0.05). The increase of omega-3 FA from 0.36 (C) to 0.60 (T1) and 0.76% (T2) must be pointed out, ( P (lt) 0.05). The omega-6 FA were also increased from 4.51 (C) to 4.94 (T1) and 6.22% (T2) (P>0.05) but omega-6: omega- 3 ratio was reduced from 12.25 (C) to 8.22 (T1) (P (lt) 0.05) and 8.62(T2), (P (lt) 0.01). Trans unsaturated FA which are undesirable were decreased from 3.37% (C) to 2.43% (T1) and 2.36% (T2)(P (lt) 0.05). From nutritional aspect those results have a great importance, having in mind that omega-3 FA have a vital role in human health.U radu su predstavljeni efekti korišćenja proizvoda 'Tradi-Lin' kao izvora omega-3 masnih kiselina u obrocima junadi u tovu. Proizvod 'TradiLin'dobijen je termičkom obradom semena lana, sadrži 58% omega-3 i 15% omega-6 masnih kiselina od ukupno polinezasićenih masnih kiselina (PUFA) i predstavlja patent francuske firme Vitalac. Ogled je izveden na tri grupe simentalske rase junadi (C, T1 i T2) sa po 15 grla u svakoj, u periodu dva meseca pred klanje. Obroci za sve grupe junadi bili su potpuno identični i bazirani na silaži cele biljke kukuruza i smeši koncentrata. Jedina razlika bila je ta što su grla pored osnovnog obroka dobijala 0, 300 i 700 g 'Tradi-Lin' -a dnevno, respektivno. Na kraju ogleda grla su zaklana i određeni su najvažniji parametri hemijskog sastava i kvaliteta mesa. Dobijeni rezultati ukazuju da u intramuskularnoj masti leđnog dela M. longissimus dorsi (MLD) nije postojala razlika u sadržaju zasićenih (50,89; 50,21; 50,32%) i nezasićenih (49,15; 49,79; 49,66%) masnih kiselina među ispitivanim tretmanima (C, T1 i T2). Međutim, dodavanje 'TradiLin'- a uticalo je na promenu strukture intramuskularne masti u korist povećanja PUFA od 4,95 (C), na 5,98 (T1) odnosno 7,31% (T2) (P (lt) 0.05). Treba posebno istaći povećanje sadržaja omega-3 masnih kiselina sa 0,36 (C) na 0,60 (T1) odnosno na 0,76% (T2), (P (lt) 0,05). Jednovremeno povećao se sadržaj omega-6 masnih kiselina od 4,51 (C) na 4,94 (T1) odnosno 6,22% (T2) (P>0,05) a odnos omega -6/omega-3 smanjen sa 12,25 (C) na 8,22 (T1) (P (lt) 0,05) i 8,62 (T2), (P (lt) 0,01). Sadržaj trans nezasićenih masnih kiselina koje su nepoželjne smanjen je sa 3,37% (C) na 2,43% (T1) (P (lt) 0,05) odnosno 2,36% (T2). Dodavanje 0,7 kg ovog preparata u obroke u zadnjih dva meseca tova potpuno je ekonomski opravdano jer utiče na zanemarljivo povećanje cene u odnosu efekte koji se dobijaju. Sa nutricionističkog aspekta ovi rezultati imaju veliki značaj imajući u vidu da omega-3 masne kiseline imaju vitalnu ulogu u očuvanju zdravlja ljudi

Fenotipski i genetski parametri reproduktivnih osobina crno belih krava sa različitim udelom HF gena

In this paper, results of the effect of direct and indirect selection of quantitative fertility traits of cattle end heritability level are presented. Study of the quantitative genetic parameters was carried out on three large farms of Black and White, Holstein-Friesian cattle. Investigation included 3900 first calving cows, daughters of 54 bull sires. The effect of genetic group of the head of cattle (genotype) and of the herd on fertility and milk traits of heifers and first calving cows of Black and White breed was investigated. Genetic group of the head of cattle (genotype) had no significant effect in variation of the fertility traits compared to general average (P (lt) 0.01). The effect of herd caused statistically significant and highly significant deviation from the general average, P (lt) 0.05 and P (lt) 0.01. Established heritability coefficients for fertility traits had low values for age at insemination (0,112), duration of pregnancy (0,045) and duration of service period (0,097). Results were obtained by applying mathematicalstatistical analysis of data - using mixed model (Harvey, 1990). Mathematical-statistical analysis of data was carried out using linear methods with fixed influence through model of Least Squares (LS method). Genotype of the head of cattle caused no significant deviation of fertility traits (P>0,05).U ovom radu su predstavljeni rezultati uticaja direktne i indirektne selekcije na kvantitativne osobine plodnosti goveda i nivo heritabiliteta. Ispitivanje kvantitativnih genetskih parametara je izvedeno na tri velike farme gde se gaje crno-bela, holštajn-frizijska goveda. Ispitivanje je uključivalo 3900 prvotelki, kćeri 54 bika-očeva. Ispitivan je uticaj genetske grupe grla goveda (genotip) i zapata na osobine plodnosti i mlečnosti junica i prvotelki crno-bele rase. Genetska grupa grla goveda (genotip) nije imala signifikantan uticaj na variranje osobina plodnosti u odnosu na opšti prosek (P (lt) 0.01). Uticaj zapata je izazvao statistički signifikantno i visoko signifikantno odstupanje od opšteg proseka, (P (lt) 0.05) and (P (lt) 0.01). Ustanovljeni koeficijenti heritabiliteta za osobine plodnosti su imali niske vrednosti za osobine uzrast pri prvoj inseminaciji (0,112), trajanje bremenitosti (0,045) i trajanje servis perioda (0,097). Rezultati su dobijeni primenom matematičko-statističke analize podataka - korišćenjem mešovitog modela (Harvey, 1990). Matematičko-statistička analiza podataka je izvršena korišćenjem linearnih metoda sa fiksnim uticajem kroz model najmanjih kvadrata (LS metod). Genotip grla goveda nije izazvao signifikantno odstupanje osobina plodnosti (P>0,05)

WELFARE INDICATORS OF DAIRY COWS - SELECTION AND IMPLEMENTATION IN ASSESSMENT

Definition, implementation, analysis of relevance and development of standards of animal welfare on cattle farms have become very important issues in the late 20th and early 21 century. Today, the most widely accepted definition of welfare is that it is the condition of an animal as a response to its attempts to cope with the effects of the environment. Depending on the type, duration and intensity of action of stimuli and the condition of the animal this struggle can be successfully or unsuccessfully completed in which case the animal welfare is endangered. But how do you assess the welfare as satisfactory and when not? In declaration of welfare as a scientific field, the turning point was the observation of its measurable character or the fact that as a result of the reaction to the effects of the stimulus in the organism of the animal changes occur at the physical, physiological, behavioural and emotional level that can be measured. Traits mentioned belong to output or animal-based welfare indicators which have a primary role in the modern methods of assessment. Unlike them, input indicators relate to information resources (resource - based) and applied management (management - based) and are important as additional information in the evaluation. Problems and the importance of selecting indicators in the assessment of the quality of welfare are still present but the practical implementation of a wide variety of assessment methodologies over time should enable better perception, analysis and even synthesis of the most relevant indicators and targets for evaluation of the different methods. This paper presents an overview of the selection, implementation and use of indicators to assess the welfare of dairy cows with a special emphasis on two current methodologies

Uzrast visokomlečnih krava kod prve oplodnje

Black and White low land dairy cattle have very pronounced ability for high production of milk. Fertility is the major trait of cattle and key factor in successful milk production. Fertility traits have pronounced variability and low heritability value. Fertility is regularly limiting factor in attempts to increase the milk yield. Age of dairy cattle at first conception is one of the major reproduction properties. Age of calves at first calving depends mainly on age at first conception. Previous researches have indicated what would be the optimum age at first conception of Black and White heifers. Age at first conception is determined by the date of birth and date of first conception. Knowledge of the strength of the environment factors on age at first conception in high yielding cows is important from the aspect of their inclusion into the model. According to the significance of individual systematic factors, their objective assessment was carried out for the purpose of accurate evaluation of obtained results. Objective of this paper is to study the age at first conception of high yielding Black and white cows through major systematic influences, by applying adequate methodology. Cows comprising the studied sample (n=331) belong to European type of Black and White dairy cattle in final stage of improving of this breed with Holstein-Friesian breed. Average age of dairy cattle at first conception was 491.19±9.36 days or 16.15±0.31 months. According to cows' the values were following: 479.31 days (> 73% HF), 486.12 days (58-73%HF) and 508.14 days ( (lt) 58% HF).Osobine plodnosti imaju izuzetno veliki ekonomski značaj koji se ispoljava kroz normalan tok proizvodnog ciklusa. Jedna od njihovih vrlo važnih specifičnosti je veoma izražena varijabilnost i niska naslednost. Uzrast grla kod prve oplodnje/teljenja je važna osobina plodnosti goveda. Crno-bela nizijska goveda imaju izraženu genetsku sposobnost za visoku proizvodnju mleka. Visokoproizvodne krave crno-bele rase izložene su tokom produktivnog veka velikom broju složenih uticaja. Uslovi proizvodnje vrlo često nisu u saglasnosti sa visokim potrebama ove rase. Problemi u reprodukciji često predstavljaju ograničavajući faktor za povećanje proizvodnje mleka. Unošenjem gena holštajn-frizijske rase u okviru programa oplemenjivanja evropskih crno-belih goveda došlo je do tendencije povećanja prinosa mleka i smanjenja plodnosti. Dosadašnja istraživanja ukazuju na prihvatljiv uzrast pri prvoj oplodnji kod junica crno-bele rase. Poznavanje jačine uticaja sredine na uzrast pri prvoj oplodnji kod visokomlečnih krava važno zbog njihovog uključivanja u model. U skladu sa pojedinačnim značajem sistematskih faktora, obavljena je njihova objektivna procena radi što tačnijeg vrednovanja ostvarenih rezultata. Cilj ovog rada je bio da se primenom odgovarajuće metodologije ispita uzrast kod prve oplodnje visokomlečnih crno-belih krava preko najvažnijih sistematskih uticaja. Krave u okviru ispitanog uzorka (n=331) pripadaju evropskim crno-belim nizijskim govedima u završnoj fazi oplemenjivanja holštajn-frizijskom rasom. Prosečna starost grla pri prvoj oplodnji iznosila je 491.19±9.36 dana ili 16.15±0.31 meseci. Posmatrano po genotipovima krava iznosio je 479.31 dana (> 73%HF), 486.12 dana (58-73%HF) i 508.14 dana ( (lt) 58%HF). Na utvrđene razlike u pogledu uzrasta pri prvoj oplodnji značajan uticaj (p≤0.05) pokazali su bikoviočevi, klasa HF gena krava nije imala značajan uticaj (p>0.05), godina teljenja pokazala je visoko značajan uticaj (p≤0.01), dok je sezona teljenja ispoljila značajan uticaj (p≤0.05)

Varijabilnost linearno ocenjenih osobina tipa bikovskih majki simentalske rase

One of the important factors of successful milk production is group of secondary traits: health, longevity, type and milking traits. These traits have become increasingly significant. In order for productive life of cows used in production of milk to be as long and as successful as possible, special attention must be directed to traits of body type and constitution. In selection of cows into the category of bull dams all heads are measured - exterior traits, and evaluated linearly for traits of type or body frame, body muscular characteristics/muscularity, form (appearance) and udder according to Regulation on method of evaluation of traits of breeding livestock (Official journal of RS, No. 21,1996). The effects of rearing region and year of measuring, i.e. evaluating were analyzed in detail using the Least Squares Method (Harvey 1987). Average values of linear evaluations of investigated heads obtained by method of Least Squares were: body frame 7,85; muscularity 7,74; form 7,66; udder 7,62. The effect of region on linear evaluation was highly significant (P (lt) 0,01). Evaluation year also influenced highly significantly (P (lt) 0,01) obtained evaluation result for form, significantly (P (lt) 0,05) obtained evaluation result for body frame and muscularity, but no effect was established on evaluation result for udder.Da bi produktivni život krava usmerenih za proizvodnju mleka bio što duži i uspešniji posebnu pažnju treba posvetiti osobinama tipa i konstitucije. Nedostaci u osobinama tipa dovode do slabije proizvodnje, lošeg zdravstvenog stanja i preranog isključenja krava iz stada. Uključivanje linearne ocene tipa u oceni priplodne vrednosti krava doprinosi pouzdanosti ocene priplodne vrednosti što se pozitivno odražava na ukupne efekte selekcije i uspešnosti proizvodnje. Pri izboru krava u kategoriju bikovskih majki sva grla su eksterijerno izmerene i linearno ocenjene za okvir, muskuloznost, formu (izgled) i vime u skladu sa Pravilnikom o načinu ispitivanja svojstava priplodne stoke (Službeni glasnik RS br. 21 iz 1996.godine). Na ispitivane linearne ocene detaljno su ispitani uticaji odgajivačkog područja i godine merenja, korišćenjem Metoda najmanjih kvadrata (Harvey 1987 ). Prosečne vrednosti linearne ocene ispitivanih grla dobijene metodom najmanjih kvadrata su: okvir grla 7,85; muskuloznost 7,74; forma 7,66; vime 7,62. Uticaj regiona na linearne ocene bio je vrlo značajan (P (lt) 0,01). Godina ocenjivanja je visoko značajno uticala (P (lt) 0,01) na ocenu forme, značajno (P (lt) 0,05) na ocenu okvira i muskuloznosti, a na ocenu vimena nije imala značaj

Mogućnosti stočarstva Srbije - perspektiva i budućnost

The paper describes the state of the livestock production in the Republic of Serbia including preliminary results from the 2012 census: according to preliminary data, 908.990 heads of cattle, 3.403.288 pigs, 1.729.278 sheep and 235.576 goats are reared in Serbia. Structural and institutional measures, and measures of credit support should be the main instruments for achieving the goals of progress in animal husbandry. Activities in the breeding-selection work should be carried out in accordance with the recommendations of international organizations (ICAR, INTERBULL, EAAP). One of the most important outcome of these activities should result in a level of over 80% of the total population of cattle, pigs, sheep and other species of domestic farm animals in Serbia included in the control of production performance (presently between 25 and 30%). Genetic improvement of cattle, sheep and pigs (milk, meat) is very complex. More efficient use of reproductive technologies (AI - artificial insemination and embryo transfer ET, etc.), also of methods for evaluation of breeding value of farm animals through new methods of evaluation of breeding value of cows and breeding bulls will contribute to faster genetic improvement of production traits of these species of domestic animals. New knowledge in mapping and gene transfer, marker assisted selection, in vitro embryo development, embryo cloning, sexing, etc., are improving rapidly, with new technologies being developed permanently. Breeding/improvement of cattle, sheep and pigs in through breeding - selection work should facilitate further improvement of fertility traits, growth rate, feed efficiency, carcass quality (higher percentage of muscle tissue in the body), the quality of milk and meat, resistance to disease and stress, etc.Početkom 2013. godine dobijeni su preliminarni rezultati popisa poljoprivrede u Republici Srbiji, obavljenog 2012. godine. Ukupan broj goveda je 908.990, svinja 3.403.288, ovaca 1.729.278 i koza 235.576 grla.. Povećanje konkurentnosti stočarstva Srbije se može ostvariti kreiranjem uslova za tržišno okruženje i putem investicija, kako u znanje, tako i u opremu. Zbog toga strukturne i institucionalne mere, kao i mere kreditne podrške treba da budu glavni instrumenti za ostvarenje ovog cilja. Aktivnosti u odgajivačko-selekcijskom radu treba da se sprovode u skladu sa preporukama međunarodnih organizacija (ICAR, INTERBULL, EAAP i druga). Jedan od najvažnijih rezultata ovog rada treba da prouzrokuje nivo od preko 80% ukupne populacije goveda, svinja, ovaca i ostalih vrsta domaćih životinja u Srbiji bude obuhvaćeno kontrolom proizvodnih svojstava (sada između 25 i 30%). Status i ciljevi oplemenjivanja goveda u Srbiji. Genetsko unapređenje goveda (mleko,meso) je vrlo kompleksno. Efikasnije korišćenje reproduktivnih tehnologija (VO-veštačko osemenjavanje i ET-embriotransfer i dr.) i korišćenje metoda za procenu odgajivačke vrednosti domaćih životinja preko novih metoda ocene priplodnih vrednosti bikova i krava će doprineti bržem genetskom unapređenju mlečnosti krava. Nova saznanja u mapiranju i transferu gena, selekciji preko markera, in vitro razvoju embriona, seksiranju i kloniranju embriona i dr. Odgajivački ciljevi-simentalska rasa, prosečna proizvodnja mleka u standardnoj laktaciji preko 6 000 kg; Holštajn frizijska rasa u standardnoj laktaciji preko 8 000 kg. Melezi iz ukrštanja domaćih krava nižih proizvodnih sposobnosti i bikova tovnih rasa, francuskih, italijanskih, engleskih. Odgajivački ciljevi ovakvog oplemenjivačkog rada i korišćenje heterozis efekta je stvaranje takvih genotipova koji će omogućiti završnu telesnu masu meleza F1, junadi od preko 550 kg, prosečni dnevni prirast u tovu preko 1500 g, randman toplih polutki preko 60%, sadržaj mišića u trupu od preko 65%. Status i ciljevi oplemenjivanja ovaca u Srbiji. Oplemenjivanje u cilju povećanja proizvodnje mesa treba da omogući dobijanje jagnjadi sa većim dnevnim prirastom (preko 300 g), veće završne mase tela sa 90 dana uzrasta (preko 28 kg), kao i većeg randmana trupa, više od 58%). Problem prelaska na policikličnost i oplodnju ovaca u toku cele godine obavio bi se na dva načina: genetički, korišćenjem ukrštanja rasa koje manifestuju estrus izvan normalne sezone (dorzet horn, il de france i romanovska) primenom metoda stimulacije, tj. indukcijom i sinhronizacijom estrusa.Tako bi se stvorili uslovi za primenu intenzivnog sistema jagnjenja dva jagnjenja u jednoj godini odnosno tri jagnjenja u dve godine. Sistem jagnjenja, sistem ukrštanja, selekcija i linijsko odgajivanje, zatim skraćenje post partum intervala i povećanje indeksa jagnjenja, kao i broja jagnjadi pri rođenju, rano zalučenje jagnjadi, korišćenje metode veštačkog osemenjavanja, automatskih mašina za dojenje, odgajivanje jagnjadi uspešnom zamenom za mleko i tov jagnjedi od 30 - 45 kg sa 90 do 120 dana. Status i ciljevi oplemenjivanja svinja u Srbiji. Oplemenjivanje svinja u cilju unapređenja mesnatosti preko odgajivačko-selekciojskog rada treba da omogući dalje poboljšanje osobina plodnosti, brzine porasta, iskorišćavanja hrane, kvaliteta trupa (veći procenat mišićnog tkiva u trupu), kvaliteta mesa i otpornosti svinja na bolesti i stres. Odgajivačko-selekcijskim radom neophodno je: povećati genetski potencijal postojećih mesnatih rasa i meleza svinja, raditi na stvaranju linija unutar čistih rasa primenom divergentne selekcije, kako bi se kasnije njihovim ukrštanjem ispoljivo veći heterozis efekat. Cilj selekcije treba da bude povećanje mišićnog tkiva u najvrednijim delovima trupa: but, plećka i kare. Odgajivački program u našoj zemlji predviđa ukrštanje landrasa (švedski, holandski,) i velikog jorkšira radi proizvodnje nazimica F1 generacije. One se posle toga ukrštaju sa nerastovima treće rase (terminalna rasa nerastova: hempšir, durok, pietren, nemački i belgijski landras) ili nerastovima F1 generacije. PR Projekat Ministarstva nauke Republike Srbije, br. TR-31053