7 research outputs found
Uticaj uzrasta pri prvoj oplodnji na reproduktivne, proizvodne i funkcionalne osobine krava simentalske rase
The effect of cow age at first insemination on productive and reproductive traits, as well as on longevity and lifetime production ones was examined in the Simmental cows housed at the 'Zlatiborski Suvati' (Mt. Zlatibor Pastures) Farm. The general linear model was used to calculate linear regression coefficients for the effect of age at first insemination on productive, reproductive traits, longevity traits and lifetime production traits The calculated linear regression coefficients suggested that the age at first insemination had a statistically significant effect (P lt 0.05) on milk, milk fat and 4% fat milk production in whole lactations (bxy=1.508, bxy=0.056 and bxy=1.464), a very high significant effect (P lt 0.001) on the age at culling and cow utilisation index ((bxy=1.386 and bxy=-0.020), and no significant effect (P>0.05) on other longevity traits. The age of cows at first insemination did not significantly affect (P>0.05) fertility and lifetime milk and milk-fat production traits. The presented results suggest that cow age at first insemination should be included in the models used in estimating breeding values of dairy cows.Uticaj uzrasta krava pri prvoj oplodnji na proizvodne i reproduktivne osobine i osobine dugoveÄnosti i životne proizvodnje ispitivan je kod krava simentalske rase smeÅ”tenih na farmi 'Zlatiborski suvati'. OpÅ”tim linearnim modelom izraÄunati su koeficijenti linearne regresije uticaja uzrasta pri prvoj oplodnji na proizvodne i reproduktivne osobine, kao i osobine dugoveÄnosti i životne proizvodnje Na osnovu izraÄunatih koeficijenata linearne regresije uzrast pri prvoj oplodnji statistiÄki je znaÄajno uticao (P lt 0.05) na proizvodnju mleka, mleÄne mast i 4% masnog mleka u celim laktacijama (bxy=1.508, bxy=0.056 i bxy=1.464), vrlo visoko znaÄajno (P lt 0.001) na uzrast pri izluÄenju i indeks iskoriÅ”Äavanja krava (bxy=1.386 i bxy=-0.020), dok na ostale osobine dugoveÄnosti nije imao signifikantan uticaj (P>0.05). Uzrast krava pri prvoj oplodnji nije imao znaÄajnog uticaja (P>0.05) na osobine plodnosti i životne proizvodnje mleka i mleÄne masti. Na osnovu prikazanih rezultata uzrast krava pri prvoj oplodnji trebalo bi uvrstiti u modele za procenu odgajivaÄke vrednosti mleÄnih krava
Uticaj sistematskih faktora na dužinu bremenitosti kod krava Simentalske rase
The effect of systematic environmental factors on gestation length in Simmental cows was evaluated by calculating the least squares mean (LSM) and its error (SELSM), by analysis of variance and by calculating the coefficient of determination (R2). The study involved Simmental cows reared at three locations, including the Zlatiborski Suvati farm (n=578), the DobriÄevo farm (n=964) and individual private farms at the VoÄar Farming Cooperative in Kotraža (n=1263). The analysis included gestation length in Simmental cows as affected by continuous systematic factors (age at first conception) and discontinuous factors such as farm, calving season, birth season, parity group, calf sex, type of birth and the interaction of these factors. The effect of age at first conception was statistically significant (P lt 0.05). The discontinuous factors had a very high significant (P lt 0.001) effect on gestation length. The coefficient of determination was as low as 0.086 (8.6%), undoubtedly suggesting the small effect of the non-genetic factors on gestation length, given the fact that the trait is biologically determined and that it shows low variability.Uticaj sistematskih faktora okoline na dužinu bremenitosti analiziran je izraÄunavanjem sredine najmanjih kvadrata (LSM) i njegove greÅ”ke (SELSM), analizom varijanse po primenjenom modelu i izraÄunavanjem koeficijenta determinacije (R2). Istraživanjem su obuhvaÄene krave simentalske rase rasporeÄene na tri lokaliteta i to farmi Zlatiborski suvati (n=578), farmi DobriÄevo (n=964) i individualna gazdinstva na podruÄju ZemljoradniÄke zadruge 'VoÄar' iz Kotraže (n=1263). Na dužinu bremenitosti ispitivan je uticaj kontinuelnih sistematskih faktora (uzrast pri prvoj oplodnji) i dikontinuelnih faktora kao Å”to su farma, sezona telenja i roÄenja, grupe partusa, pola teladi, tipa roÄenja i interakcija pomenutih faktora. Uticaj uzrasta pri prvoj oplodnji bio je statistiÄki znaÄajan (P lt 0.05), dok uticaj svih diskontinuelnih uticaja na trajanje bremenitosti bio je vrlo visoko znaÄajan (P lt 0.001). Koeficijent determinacije iznosio je svega 0.086 (8.6%), Å”to nedvosmisleno ukazuje na mali uticaj paragenetskih faktora na ispoljenost dužine bremenitosti obzirom da je ona bioloÅ”ki data i da se odlikuje niskom varijabilnoÅ”Äu
Uticaj sistematskih faktora na osobine dugoveÄnosti kod krava simentalske rase
The effects of fixed non-genetic factors (farm, season of birth, year of birth, total number of lactations) and a continuous non-genetic factor (age at first conception) on the expression and variability of longevity traits such as age at culling, length of productive life, days in milk and cow efficiency index were investigated in 2548 Simmental cows in three farming areas. Based on the model used for the analysis of the effects of non-genetic factors, including the environment and cow age at first conception, on the expression and variability of longevity traits, the overall means for age at culling, length of productive life, days in milk and cow efficiency index were 2445.21Ā±17.49 days, 1562.55Ā±17.71 days, 1094.17Ā±12.28 days and 58.68Ā±0.32%, respectively. The effect of farming area, year of birth and lactation group on longevity traits was very significant (P lt 0.01), whereas the effect of season of birth was significant (P lt 0.05). Age at first conception had a highly significant (P lt 0.01) effect on age at culling, length of productive life and cow efficiency index, and no significant effect on days in milk (P>0.05). Based on the model used, the coefficients of determination (R2 ) were very significant (P lt 0.01) for all longevity traits, and ranged from 0.898 for age at culling to 0.959 for days in milk.Uticaj fiksnih (farma, sezona i godina roÄenja, ukupan broj laktacija) i kontinuelnih (uzrast pri prvoj oplodnji) sistematskih faktora na ispoljenost i varijabilnost osobina dugoveÄnosti kao Å”to su uzrast pri izluÄenju, dužina produktivnog života, ukupan broj muznih dana i indeks iskoriÅ”Äavanja krava prouÄavan je na uzorku od 2548 simentalskih krava rasporeÄenih na tri odgajivaÄka podruÄja. Na osnovu primenjenog modela za analizu uticaja sistematskih faktora okoline i uzrasta krava pri prvoj oplodnji na ispoljenost i varijabilnost osobina dugoveÄnosti opÅ”ti prosek za uzrast pri izluÄenju, dužinu produktivnog života, ukupan broj muznih dana i indeks iskoriÅ”Äavanja krava iznosio je 2445,21Ā±17,49 dana, 1562,55Ā±17,71 dana, 1094,17Ā±12,28 dana i 58,68Ā±0,32%. Uticaj odgajivaÄkog podruÄja, godine roÄenja i grupe laktacija na osobine dugoveÄnosti bio je vrlo znaÄajan (P lt 0.01), dok je uticaj sezone roÄenja krava bio znaÄajan (P lt 0.05). Uzrast pri prvoj oplodnji visoko znaÄajno (P lt 0.01) je uticao na uzrast pri izluÄenju, dužinu produktivnog života i indeks iskoriÅ”Äavanja krava, dok na ukupan broj muznih dana nije imao znaÄajan uticaj (P>0.05). Dobijeni koeficijenti determinacije (R2 ), na osnovu primenjenog modela, za sve osobine dugoveÄnosti bili su vrlo znaÄajni (P lt 0.01) i kretali su se od 0,898 kod uzrasta pri izluÄenju do 0,959 kod ukupnog broja muznih dana
Uticaj sistematskih faktora na proizvodnju 4% mast korigovanog mleka kod krava simentalske rase
The effect of systematic and continuous environmental factors on 4% fat corrected milk (FCM) yield in 2805 Simmental cows over whole and standard lactations was evaluated using the general linear model. The test systematic or fixed factors included the effect of farm or breeding area, calving season, year of birth, season of birth, lactation group and interactions between year of birth and season of birth, breeding area and calving season, and breeding area and lactation group. The continuous factor analysed was the effect of age at first conception. The effect of breeding area, lactation group and calving season on 4%FCM yield over whole and standard lactations was found to be very highly significant (P lt 0.001). The interactions of fixed i.e. systematic factors involved in the model, including those between year and season of birth, breeding area and calving season, and farm and lactation group had a very highly significant effect (P lt 0.001) on 4% FCM yield over both whole and standard lactations. The age at first conception, as a continuous factor, showed a very highly significant effect (P lt 0.001) on 4% FCM yield over both whole and standard lactations. The model used to correct the 4%FCM yield over whole and standard lactations for the effect of systematic factors was very highly significant (P lt 0.001). The variance of the model accounted for 15.93% and 21.55% of the total variance in 4% FCM yield over whole and standard lactations, respectively. The resulting coefficient of determination (R2) in 4% FCM yield was 0.159 over whole lactations and 0.216 over standard lactations.Analiza uticaja sistematskih i kontinuelnih faktora okoline na proizvodnju 4% mast-korigovanog mleka u celim i standardnim laktacijama kod 2805 krava simentalske rase izvrÅ”ena je primenom opÅ”teg linearnog modela. Od sistematskih odnosno fiksnih faktora analiziran je uticaj farme ili odgajivaÄkog podruÄja, sezone telenja, godine i sezone roÄenja, grupe laktacija i interakcije izmeÄu godine i sezone roÄenja, odgajivaÄkog podruÄja i sezone telenja i odgajivaÄkog podruÄja i grupe laktacija. Od kontinuelnih faktora posmatran je uticaj uzrasta pri prvoj oplodnji. Uticaj odgajivaÄkog podruÄja, grupe laktacija i sezone telenja na proizvodnju 4%MKM u celim i standardnim laktacijama bila je vrlo visoko znaÄajna (P lt 0.001). Interakcije fiksnih, odnosno sistematskih faktora, ukljuÄenih u model, kao Å”to su interakcija izmeÄu godine i sezone roÄenja, zatim odgajivaÄkog podruÄja i sezone telenja i farme i grupe laktacija, na proizvodnju 4%MKM kako u celim tako i u standardnim laktacijama imale su vrlo visoko znaÄajan uticaj (P lt 0.001). Uzrast pri prvoj oplodnji, kao kontinuelni faktor, statistiÄki vrlo visoko znaÄajno (P lt 0.001) je uticao na proizvodnju 4% mast-korigovanog mleka i u celim i u standardnim laktacijama. Primenjeni model za korekciju proizvodnje 4%MKM u celim i standardnim laktacijama na dejstvo sistematskih faktora bio je vrlo visoko znaÄajan (P lt 0.001). Udeo varijanse modela u ukupnoj varijansi kretao se od 15.93% kod proizvodnje 4%MKM u celim laktacijama do 21.55% kod proizvodnje 4%MKM u standardnim laktacijama. Dobijeni koeficijenti determinacije (R2) kod proizvodnje 4%MKM u celim i standardnim laktacijama iznosili su 0.159 i 0.216
Modern Approach to the Enigma of Bovine Respiratory Disease Complex: A Review
Research on bovine respiratory disease complex (BRDC) has strongly contributed to a better understanding of disease at both global and local levels. New agents have been identified and their nature has been better known since then, as well as all the factors that predispone the development of BRDC. Serious work in a number of researches has led to results that have proven significant synergistic interactions between viruses and bacteria that lead to the BRDC and complicate the prevention and treatment of the diseased cattle. Nowadays, it is necessary to apply the latest molecular and other techniques in order to examine in detail all of the specific causes, describe them accurately and provide effective prevention. This can primarily be accomplished by producing different types of vaccines, which are to be improved constantly. Serious progress has been made in researches on immunogenic properties and antimicrobial activity of various natural and synthetic substances in order to improve the production of more effective vaccines for control, as well as the development of a new generation of antibiotics to treat the disease. BRDC prevention programs have been successful, in which great importance was given to proper vaccinations and herd management practices. BRDC is still the most important disease of cattle from an economic point of view, since it causes great losses and expenses. (C) 2013 PVJ. All rights reserve
Revidirani kvantitativni indeks osjetljivosti na inzulin: povezanost sa metaboliÄkim statusom krava tijekom rane laktacije
The revised quantitative insulin sensitivity check index (RQUICKI) is the most commonly used indicator of insulin resistance in dairy cows. The aim of this study was to examine the characteristics of metabolic status in cows with different RQUICKI index values during early lactation. The experiment included 40 Holstein-Friesian cows in the first week of lactation. The cows were classified into four groups according to quartile (Q 1 to 4) values of RQUICKI indexes: Q1 = 0.35-0.41 (most insulin resistant), Q2 = 0.42-0.52, Q3 = 0.53-0.67, Q4 = 0.68-0.77 (most insulin sensitive). Metabolic parameters were significantly different in early lactation cows, classified according to the values of the RQUICKI index. The cows that were the most resistant to insulin (Q1) had higher levels of non-esterified fatty acid (NEFA), cortisol, somatotropic hormone (STH), beta-hydroxybutyrate (BHB), total bilirubin, aspartate aminotransferase (AST), malondialdehyde (MDA) and body condition score (BCS) in comparison to the cows that were the least resistant to insulin (Q4). The cows also had lower levels of insulin-like growth factor I (IGF-I), triiodothyronine (T3), thyroxine (T4), albumin, cholesterol, triglycerides, Ca and P as well as a tendency towards lower insulin and glucose concentrations. Metabolic parameters were strongly regressed by RQUICKI in the most insulin resistant cows (Q1) in relation to the cows in the other groups, Q2-4. The cows with a higher number of metabolic abnormalities in their metabolic profiles had lower RQUICKI values: 0.56 Ā± 0.045 (no abnormalities); 0.52 Ā± 0.041 (1 abnormality); 0.47 Ā± 0.042 (2 abnormalities) and 0.4 Ā± 0.043 (ā„3 abnormalities). We concluded that the RQUICKI index could be applied in order to accurately identify metabolic status in cows during early lactation. However, the kinetics of insulin sensitivity should be further studied using more animals per group, as well as in other breeds of cowsRevidirani kvantitativni indeks provjeravanja osjetljivosti na inzulin (RQUICKI) najÄeÅ”Äe se koristi kao pokazatelj otpornosti na inzulin u krava. Cilj ovoga istraživanja bio je ustvrditi karakteristike metaboliÄkog statusa u krava s razliÄitom vrijednosti RQUICKI indeksa u ranoj laktaciji. Pokus je ukljuÄivao 40 krava Holstein-Friesian pasmine. Krave su razvrstane u Äetiri skupine prema kvartilima (Q 1 do 4) vrijednosti RQUICKI indeksa: Q1 = 0,35-0,41 (najrezistentnije na inzulin), Q2 = 0,42-0,52, Q3 = 0,53-0,67, Q4 = 0,68-0,77 (najosjetljivije na inzulin). MetaboliÄki parametri bili su znakovito razliÄiti u krava u ranoj laktaciji razvrstanima prema vrijednostima RQUICKI indeksa. Krave koje su bile najrezistentnije na inzulin (Q1) imale su i veÄe razine NEFA, kortizola, STH, BHB, ukupnog bilirubina, AST, MDA i bolju tjelesnu kondiciju u usporedbi s kravama koje su bile najmanje osjetljive na inzulin (Q4). TakoÄer, te su krave imale niže koncentracije IGF-I, T3, T4, albumina, kolesterola, triglicerida, Ca i P te sklonost smanjenju koncentracije inzulina i glukoze. U skupini krava koje su najrezistentnije na inzulin (Q1) regresijska analiza je pokazala jaÄu povezanost izmeÄu metaboliÄkih parametara i RQUICKI nego Å”to je to bio sluÄaj u ostalim skupinama krava (Q2, Q3 i Q4). Krave s veÄim brojem metaboliÄkih abnormalnosti profila imale su nižu vrijednost RQUICKI: 0,56 Ā± 0,045 (bez abnormalnosti); 0,52 Ā± 0,041 (jedna abnormalnost); 0.47 Ā± 0.042 (dvije abnormalnosti) i 0.4 Ā± 0.043 (ā„3 abnormalnosti). ZakljuÄujemo da bi se RQUICKI indeks mogao primijeniti za toÄnije identificiranje metaboliÄkog statusa krava tijekom rane laktacije. MeÄutim, kinetika osjetljivosti na inzulin trebala bi se dodatno istražiti na veÄem broju životinja kao i u krava razliÄitih pasmina
Determination of blood serum calcium, inorganic phosphorus and magnesium in different productive stages of Holstein dairy cows
Introduction. The aim of this study was to determine and compare levels of blood serum calcium, inorganic phosphorus and magnesium in the peripartal period and during mid lactation in Holstein dairy cattle.Materials and Methods. Blood samples were collected from 12 cows in late pregnancy, 12 early lactation cows, and 12 mid lactation cows.Results and Conclusions. Serum calcium and inorganic phosphorus in blood of dairy cows in early and mid lactation were significantly lower compared to the values in the blood serum of dairy cows in late pregnancy, probably indicating the increased use of these macro elements by the mammary gland at the early stages of lactation. When the cows were in the lactation period, blood serum magnesium levels were significantly lower compared to the values of dairy cows during late pregnancy, probably indicating the increased use of magnesium by the dairy cows during lactation. The results show that the homeostasis of the macro elements examined in the blood of transition and mid lactation dairy cows was maintained, suggesting their adequate supply from alimentary sources