The estimate of energy intake and reproductive activity in high producing dairy cows

Uspostavljanje spolnog ciklusa kod visokomliječnih krava nakon teljenja česti je problem na farmama koje imaju intenzivnu proizvodnju mlijeka. Visoka proizvodnja mlijeka zahtijeva povećani unos energije i drugih hranjiva potrebnih za sintezu mlijeka i u slučaju njihova nedostatka dolazi do metaboličkih i reproduktivnih poremećaja tijekom laktacije. U radu je analizirana razina opskrbljenosti krava sa energijom te reproduktivni pokazatelji kod visokomliječnih krava. Na temelju sadržaja proteina i uree te odnosa sadržaja mliječne masti i proteina u mlijeku utvrđeno je da 17,5 % uzoraka mlijeka potječe od krava nedovoljno opskrbljenih energijom. Razdoblje rane laktacije (prvih 60 dana) je najosjetljivije razdoblje s obzirom na dostatnu opskrbu energijom i proteinima kod krava na što ukazuje činjenica da 45 % uzoraka mlijeka analiziranih u ovom razdoblju ukazuje na deficit unosa energije, a u 16,5 % uzoraka utvrđen je omjer masti i proteina u mlijeku (IMB) >1,5 što sugerira opsežnu mobilizaciju masti iz tjelesnih rezervi i pojavu metaboličkih poremećaja. Uspostava spolnog ciklusa izražena kao razdoblje do prvog pripusta u većine krava bila je unutar 90 dana nakon teljenja (74 %) dok u svega 9 % krava to razdoblje je bilo dulje od 120 dana. Unatoč tome u čak 32 % krava graviditet je nastupio iza 120. dana laktacije što ukazuje na izostanak ovulacije i/ili postojanja nepovoljnih uvjeta za preživljavanje embrija (rana embrionalna smrtnost). Povezanost između pojedinih sastojaka mlijeka i reproduktivnih pokazatelja nije utvrđena.Establishing the ovarian cycle in high-yielding dairy cows after calving is a common problem on farms with intensive milk production. High milk production requires an increased intake of energy and other nutrients necessary for milk synthesis, and in case of their deficiency, metabolic and reproductive disorders occur during lactation. In this paper we analyzed the energy intake and the reproductive indicators of high yielding dairy cows. Based on the protein and urea content and the ratio of milk fat and protein content, it was determined that 17.5% of the milk samples came from cows with insufficient energy intake. The period of early lactation (the first 60 days) is the most sensitive period in cows regarding to the sufficient energy and proteins intake. Results showed that 45% of the milk samples analyzed in this period have a deficit in energy intake, and in 16.5% of the samples, IMB was higher than 1.5, which suggests extensive mobilization of fat from body storages and the appearance of metabolic disorders. The establishment of the ovarian cycle expressed as the period until the first mating, in most cows was within 90 days after calving (74%), while in only 9% of cows this period was longer than 120 days. Despite this, in more than 32% of cows, pregnancy occurred after the 120th day of lactation, which indicates the absence of ovulation and/or the existence of unfavorable conditions for embryo survival (early embryonic mortality)

The estimate of energy intake and reproductive activity in high producing dairy cows

Uspostavljanje spolnog ciklusa kod visokomliječnih krava nakon teljenja česti je problem na farmama koje imaju intenzivnu proizvodnju mlijeka. Visoka proizvodnja mlijeka zahtijeva povećani unos energije i drugih hranjiva potrebnih za sintezu mlijeka i u slučaju njihova nedostatka dolazi do metaboličkih i reproduktivnih poremećaja tijekom laktacije. U radu je analizirana razina opskrbljenosti krava sa energijom te reproduktivni pokazatelji kod visokomliječnih krava. Na temelju sadržaja proteina i uree te odnosa sadržaja mliječne masti i proteina u mlijeku utvrđeno je da 17,5 % uzoraka mlijeka potječe od krava nedovoljno opskrbljenih energijom. Razdoblje rane laktacije (prvih 60 dana) je najosjetljivije razdoblje s obzirom na dostatnu opskrbu energijom i proteinima kod krava na što ukazuje činjenica da 45 % uzoraka mlijeka analiziranih u ovom razdoblju ukazuje na deficit unosa energije, a u 16,5 % uzoraka utvrđen je omjer masti i proteina u mlijeku (IMB) >1,5 što sugerira opsežnu mobilizaciju masti iz tjelesnih rezervi i pojavu metaboličkih poremećaja. Uspostava spolnog ciklusa izražena kao razdoblje do prvog pripusta u većine krava bila je unutar 90 dana nakon teljenja (74 %) dok u svega 9 % krava to razdoblje je bilo dulje od 120 dana. Unatoč tome u čak 32 % krava graviditet je nastupio iza 120. dana laktacije što ukazuje na izostanak ovulacije i/ili postojanja nepovoljnih uvjeta za preživljavanje embrija (rana embrionalna smrtnost). Povezanost između pojedinih sastojaka mlijeka i reproduktivnih pokazatelja nije utvrđena.Establishing the ovarian cycle in high-yielding dairy cows after calving is a common problem on farms with intensive milk production. High milk production requires an increased intake of energy and other nutrients necessary for milk synthesis, and in case of their deficiency, metabolic and reproductive disorders occur during lactation. In this paper we analyzed the energy intake and the reproductive indicators of high yielding dairy cows. Based on the protein and urea content and the ratio of milk fat and protein content, it was determined that 17.5% of the milk samples came from cows with insufficient energy intake. The period of early lactation (the first 60 days) is the most sensitive period in cows regarding to the sufficient energy and proteins intake. Results showed that 45% of the milk samples analyzed in this period have a deficit in energy intake, and in 16.5% of the samples, IMB was higher than 1.5, which suggests extensive mobilization of fat from body storages and the appearance of metabolic disorders. The establishment of the ovarian cycle expressed as the period until the first mating, in most cows was within 90 days after calving (74%), while in only 9% of cows this period was longer than 120 days. Despite this, in more than 32% of cows, pregnancy occurred after the 120th day of lactation, which indicates the absence of ovulation and/or the existence of unfavorable conditions for embryo survival (early embryonic mortality)

Prof. dr. sc. Tomislav Balenović (1942. - 2020.)

Dugogodišnji nastavnik Zavoda za stočarstvo, danas Zavoda za uzgoj životinja i stočarsku proizvodnju Veterinarskog fakulteta Sveučilišta u Zgrebu, te urednik časopisa Stočarstvo prof. dr. sc. Tomislav Balenović preminuo je 18. prosinca 2020. godine u 79-oj godini života. Na vječni počinak ispraćen je tiho, u krugu obitelji te najbližih prijatelja i suradnika. Opraštamo se od poštovanog profesora, kolege, znanstvenika i stručnjaka te učitelja mnogih uspješnih generacija doktora veterinarske medicine

Black slavonian pig

Crna slavonska svinja je autohtona hrvatska pasmina čiji nastanak datira iz druge polovine 19 stoljeća. Stvorio ju je grof Pfeier križanjima krmača Crne Mangalice s Berkšir nerastima, a križanci su povremeno popravljani križanjem s Poland China nerastima. Do 1950-tih Crna slavonska svinja bila je najraširenija pasmina u Slavoniji i uvelike se koristila za proizvodnju masti i tradicionalnih mesnih proizvoda. Uvođenjem modernih pasmina i križanaca, broj Crnih slavonskih svinja drastično se smanjio te je tijekom 1990-tih opstanak pasmine postao ugrožen. Kao rezultat poduzetih mjera zaštite i državnih poticaja efektivna populacija dosta se povećala posljednjih godina te je u 2008. godini brojala 78 nerasta i 669 krmača. Pasmina je dobro prilagođena za držanje na otvorenom i tra- dicionalni sustav uzgoja koji uključuje iskorištavanje pašnjaka i šumskih ispaša uz prihranu malim količinama žitarica. Veličina legala je mala, u prosjeku 7 do 8 prasadi. Tovne sposobnosti također su skromne uz niske dnevne priraste i visok udio masti u trupu. Među- tim, pasmina se odlikuje dobrom kakvoćom mesa uz posebice visok udio intramuskularne masnoće (6-7%) i visoku vrijednost mesnih prerađevina. Povećanje proizvodnje i razvoj tržišta tradicionalnih mesnih proizvoda, kao što je Slavonski kulen, može u budućnosti predstavljati najbolji put za dugoročno očuvanje Crne slavonske pasmine kao sastavnog dijela biološke raznolikosti.Black Slavonian pig is an autochthonous Croatian breed created in the second half of the 19th century. Until the 1950s it was the most widespread breed in the Slavonia, mainly used for the production of fat and meat products. Recently, the population was drastically reduced and in 1990s the survival of the breed was endangered. Due to current protection measures the eective population rather increased; in 2006 there were 46 boars and 604 sows. The breed is well adopted for outdoor keeping. Traditional production includes the utilization of pasture and woodland with supplement of a small amount of grains. Litter size of the breed is low, on average 7-8 piglets. The fattening abilities are also modest, with low daily gains and high share of fat in the carcass. However, the meat quality is good, with high content of intramuscular fat (6-7%) and high appreciation of its meat products, like Slavonian kulen sausage. As a part of current trends of support of sustainable and traditional food production systems, it becomes important to preserve the pro- duction systems of local breeds and their products. Increase in production of traditional meat products, like Slavonian kulen, could be the best way for long-term preservation of Black Slavonian breed as an integral part of future biological diversity

STOČARSKA PROIZVODNJA KAO OSNOVA BUDUĆE SURADNJE IZMEĐU ZEMALJA KVADRILATERALE

This paper gives the main characteristics of animal production in Croatia and analyzes its competitiveness as a basis for possible collaboration between the countries of Quadrilateral in the field of animal production. It describes the current state and recent trends in milk and meat production and their perspective after Croatian accession to EU. Particular emphasis is put on the analysis of trade relations with countries of the Quadrilateral. The main characteristic of Croatian livestock production is the small average farm size and low productivity what could be the main reasons for a general inefficient domestic livestock production and dependence on import of both live animals and animal products (milk and meat). In order to increase the competitiveness of Croatian farmers’ and meet the increasing for milk and meat additional farm concentration and the cooperation of small holders as well as a more effective use of local resources such as land, labour and livestock tradition is necessary. In addition, after EU accession Croatian livestock sector can expect further integration in international trade and better opportunities for export (e.g. elimination of protective tariffs) on common EU market, especially with regard to products that are lacking in EU (e.g. beef). In this way collaboration between countries of Quadrilateral through development and implementation of new technologies can contribute to a better use of specific national resources and better production efficiency.U radu su prikazana glavna obilježja stočarske proizvodnje u Hrvatskoj te je analizirana njena konkurentnost u odnosu na zemlje kvadrilaterale kao temelj za buduću suradnju na području animalne proizvodnje. Opisano je trenutno stanje i najnoviji trendovi u proizvodnji mlijeka i mesa u Hrvatskoj kao i njihova perspektiva nakon ulaska Hrvatske u EU. Poseban naglasak je stavljen na analizu trgovinskih odnosa sa zemljama kvadrilaterale. Glavno obilježje hrvatske stočarske proizvodnje je mala prosječna veličina gospodarstva i niska produktivnosti što bi mogao biti glavni razlog za opću neučinkovit domaće stočarske proizvodnje i ovisnost o uvozu kako živih životinja tako i proizvoda životinjskog podrijetla (mlijeko i meso). U cilju povećanja konkurentnosti neophodna je daljnja koncentracija stočarske proizvodnje, veća suradnja malih proizvođača kako bi se što uspješnije koristili lokalni resursi kao što su zemljište, radna snaga i stočarska tradicija. Osim toga, nakon pristupanja EU hrvatskom stočarskom sektoru se otvara mogućnost lakše integracije na međunarodno tržište te mogućnost izvoza (npr. ukidanje zaštitnih carina) na zajedničko tržište EU, posebice s obzirom na proizvode koji nedostaju u EU (npr. govedina). Suradnja između zemalja kvadrilaterale kroz razvoj i implementaciju novih tehnologija može pridonijeti boljem korištenju specifičnih nacionalnih resursa kojima raspolažu pojedine zemlje, a samim time i većoj efikasnosti u proizvodnji

Estimation of population differentiation using pedigree and molecular data in Black Slavonian pig

Submitted 2020-07-17 | Accepted 2020-08-24 | Available 2020-12-01https://doi.org/10.15414/afz.2020.23.mi-fpap.241-249The aim of the study was to investigate the genetic differentiation of the Black Slavonian pig population. Two parallel analyses were performed using genealogical records and molecular data. Pedigree information of 6,099 pigs of the Black Slavonian breed was used to evaluate genetic variability and population structure. Additionally, 70 pigs were genotyped using 23 microsatellite markers. Genealogical data showed shrinkage in genetic diversity parameters with effective population size of 23.58 and inbreeding of 3.26%. Expected and observed heterozygosity were 0.685 and 0.625, respectively, and the average number of alleles per locus was 7.826. Bayesian clustering algorithm method and obtained dendrograms based on pedigree information and molecular data revealed the existence of four genetic clusters within the Black Slavonian pig. Wright’s FIS, FST and FIT from pedigree records were 0.017, 0.006, and 0.024, respectively, and did not prove significant population differentiation based on the geographical location of herds, despite the natural mating system. Obtained results indicate that despite the increased number of animals in the population, genetic diversity of Black Slavonian pig is low and conservation programme should focus on strategies aimed at avoiding further loss of genetic variability. Simultaneous use of genealogical and molecular data can be useful in conservation management of Black Slavonian pig breed.Keywords: autochthonous pig breed, microsatellite, genealogical data, genetic structuringReferencesBarros, E. A., Brasil, L. H. de A., Tejero, J. P., Delgado-Bermejo, J. V. & Ribeiro, M. N. (2017). Population structure and genetic variability of the Segureña sheep breed through pedigree analysis and inbreeding effects on growth traits. Small Ruminant Research, 149, 128-133.Belkhir, K. (2004). 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Varijabilnost dušičnih sastojaka ovčjeg mlijeka sub-mediteranskog područja

The aim of this study was to evaluate seasonal variation in urea content and other nitrogen compounds (protein, casein, non-protein nitrogen content) of sheep milk as a tool for monitoring the protein nutritional status over the period of two years. The study was performed on three family farms with 150 to 300 sheep per farm using semi-extensive farming management based on pasture, typical for sub-Mediterranean area. Bulk-tank milk samples were taken during the entire milking period (from March to July or August, depending on the year) and were analysed for protein, casein, non-protein nitrogen (NPN) and urea content. Significant effect of the year was observed on urea and NPN content (P<0.05). In addition, seasons had a significant effect on milk protein, urea and casein content (P<0.01). Variations in nitrogen components of sheep milk in Dalmatian hinterland have been significant due to the fact that the semi-extensive farming systems could be strongly affected by climate which directly influence on the quantity and quality of pasture.Cilj ovog rada bio je utvrditi sezonske varijacije sadržaja uree i drugih dušičnih sastojaka (bjelančevina, kazeina i neproteinskog dušika) ovčjeg mlijeka kao alata za praćenje proteinskog hranidbenog statusa ovaca. Istraživanje je provedeno u razdoblju od dvije godine na tri obiteljska poljoprivredna gospodarstva s polu-ekstenzivnim uzgojem ovaca (od 150 do 300 ovaca po stadu). Uzgoj je baziran na ispaši na prirodnim pašnjacima, što je karakteristično za sub-mediteransko područje. Prikupljeni su skupni uzorci ovčjeg mlijeka tijekom mužnje (od ožujka do srpnja ili kolovoza, ovisno o godini). Uzorci su analizirani na sadržaj proteina, kazeina, neproteinskog dušika (NPN) i uree. Utvrđen je značajan (P<0,05) utjecaj godine na koncentraciju uree i NPN-a. Povrh toga, sezona je značajno (P<0,01) utjecala na sadržaj proteina, uree i kazeina u ovčjem mlijeku. Varijacije dušičnih sastojaka ovčjeg mlijeka u Dalmatinskoj Zagori posljedica su polu-ekstenzivnog načina uzgoja ovaca, osjetnog utjecaja klimatskih čimbenika koji izravno utječu na količinu i kvalitetu paše