Nevena Maksimovic - Academia.edu (original) (raw)

Papers by Nevena Maksimovic

Biotehnologija u stocarstvu

The investigation was conducted in population of Mis breed of sheep, divided into three groups. F... more The investigation was conducted in population of Mis breed of sheep, divided into three groups. For reproduction had use rams of Ile de France breed. Induction and synchronization of oestrus was done off-season in October. The percentage of lambing sheep, sheep fertility, and number of lambs acquired per father, sex and birth type of lambs were observed. Ram 1 had a highest number of ewes lambed with an excellent percentage of mating success and highest fertility rate of ewes with differences on fertility rate of 17% (between group of ewes in ram 1 and ram 2), 36% (group of ewes in ram 1 and ram 3) and 19% (group of ewes in ram 2 and ram 3).The highest birth weight were on lambs born single from ram 3, born twins from ram1, triplets of ram 3. For the lambs born quadruplets (unfortunately only in rams 1 and 2 with one lamb of each was alive) the lamb of ram 2 was higher in birth weight. The male and female lambs of ram 3 got the highest birth weight while the female lambs of ram 1 ac...

The purpose of this study was to investigate fertility in the ewes of MIS sheep population follow... more The purpose of this study was to investigate fertility in the ewes of MIS sheep population following synchronized oestrus in anoestrus season and natural oestrus during breeding season. Research was carried out on an experimental sheep farm of the Institute for Animal Husbandry in Belgrade. The study included 76 ewes and 6 rams of MIS sheep population (three breed crosses of Pirot Pramenka, Württemberg and Ile de France breed). In anoestrus season, oestrus was synchronized in 43 ewes using progestagen impregnated vaginal sponges (30 mg fluorogestone acetate) in combination with 750 IU PMSG. During the breeding season, 33 ewes were bred naturally to 6 rams, without the use of exogenous hormones. Teaser rams with marking-harnesses and abdominal aprons were used to detect females in oestrus. Obtained fertility and productivity results in anoestrus and breeding season were as follows: lambing rate 69.77% (30/43) and 100% (33/33) (P<0.05)

The study investigates the possibility of oestrus synchronization in ewes of MIS sheep population... more The study investigates the possibility of oestrus synchronization in ewes of MIS sheep population using prostaglandin (PG) outside the breeding season, serum progesterone concentration for pregnancy diagnosis and effect of hCG (human chorionic gonadotropin) on reproductive parameters. Prostaglandin was used to induce oestrus at the dose of 2.5 ml/ewe, administered intramuscularly in two injections (with 11 days interval). Responsive ewes were bred to rams and were divided into two groups, one of which was administered with hCG at the dose of 300 IU i/m 7th day post mating and the second group which was used as a control. Serum progesterone was measured on the day of prostaglandin administration and 17 days post mating. Oestrus response was 66.67%, lambing rate was 70%, average litter size was 1.7 lambs/ewe and twinning rate was 60%. Administration of hCG 7 days post mating did not improve fertility results. Lambing, prolificacy and twinning rates were higher in control than in hCG g...

On a small closed population of Mis sheep the relationship was studied of the influence of inbree... more On a small closed population of Mis sheep the relationship was studied of the influence of inbreeding on body weight growth from birth to the age of 18 months and sperm DNA fragmentation in rams. Two groups of male lambs were used. First was composed of outbred, while the second of inbred animals with inbreeding coefficient over 25%. Differences in body weight and daily gain related to the presence of inbreeding in the pedigree were not found significant (P>0.05). The mean value of sperm chromatin damage in rams of the outbred group varied from 1.93 to 12.37%, (mean = 7.32%) and in inbred group from 13.76 to 37.67% (mean = 25.23%). Significant difference was identified between the outbred and inbred rams in the mean percentage of sperm damaged (P<0.01).

Large Animal Review, 2020

The investigation was performed on two groups of primiparous and multiparous healthy Alpine dairy... more The investigation was performed on two groups of primiparous and multiparous healthy Alpine dairy goats (25 each) during lactation. Blood samples were collected (jugular venipuncture) 10-15 days before and 10-15 and 30 days after the parturition into BD SST-II Advance (3.5 mL) and BD NaF 3.0 mg Na2EDTA 6.0 mg (2 mL) vacutainers, cooled and centrifuged (1500 r/min, 15 minutes). Glucose, non-esterified fatty acids (NEFA) and β-hydroxybutyrate (BHBA) concentrations in blood sera were determined using A15 automatic spectrophotometric analyzer (Biosystem, Spain). Simultaneously, body condition scoring (BCS) was performed by Villaquiran et al. (2007) method. The obtained data were analyzed by IBM SPSS statistics 21. The glucose concentration inclined to increase in both groups. Differences between glucose levels were significant (p<0.05) 15 days before and 15 days after, as well as 15 and 30 days after the parturition, and very significant (p<0.01) 15 days before and 30 days after t...

The study aim was to know the non-genetic factors and the interaction effect on birth weight of l... more The study aim was to know the non-genetic factors and the interaction effect on birth weight of lambs F1 generation crossed Mis x Ile de France. The data of lambs birth weight (in kg), month of birth, year of birth, season of birth, sex, birth type from progeny (F1 generation) of crossing Mis x Ile de France with a total of 388 lambs born during 2018 to 2019 recorded. The General Linear Model (GLM) procedure was used to analyze the data. The analysis of variance has shown that month of birth significantly affects lambs birth weight (P<.005). Results shows a highly significant effect of year on lambs birth weight (P<.001). The highest mean average birth weight of lambs showed on the second year. Regarding of season, lambs had the highest body weight in spring and winter, and the smallest in autumn but despite the differences in weight, season did not show any significant effect on lambs birth weight (P>.005). Sex of lambs showed no significant effect on lambs birth weight (P>.005). The birth type significantly affects birth weight of lambs (P<.001). The highest body weight are have single, then twins, triplets and quadruplets.

The goal of this review is to discuss the most important issues in the dairy cattle welfare chall... more The goal of this review is to discuss the most important issues in the dairy cattle welfare challenges that facing the dairy industry today and tomorrow, namely dairy cattle welfare indicators and standards and the most significant welfare problems, and to illustrate the role of science in addressing these challenges. It should be noted that producers have always been concerned about the condition of dairy cattle and have tried to ensure that they are healthy and well nourished. In this tradition of the dairy cattle care, good welfare is seen largely as the absence of illness or injury and malnutrition. More recent concerns about dairy cattle welfare have focused on the pain and distress that the cattle might experience as a result of widely accepted management practices, and the possibility that the animals suffer as a result of being kept under apparently inadequate conditions. The evidence suggests that, whilst improvements to the welfare of dairy cows in the developed and develo...

The area of central Serbia is very suitable area for small ruminant production, due to it's hilly... more The area of central Serbia is very suitable area for small ruminant production, due to it's hilly-mountainous region, rich in pastures, and free from heavy use of pesticides, which make it great for organic production. In the territory of central Serbia, representative of autochthonous (indigenous) sheep breeds is pramenka (zackel) with its differentiated strains: Sjenica strain, Svrljig strain, Krivovir strain, Karakachan strain, Pirot strain, Lipa strain and Bardoka (White Metohian strain). Aim of this study was to investigate Lipa strain: number of controlled heads, their productivity parameters and milk parameters. Observed data were processed using the statistical package Statistica for Windows (Stat. Soft Inc.), whereby the basic parameters of descriptive statistics (arithmetic mean, variation coefficient, standard deviation and standard error) were calculated. In this study, total of 840 adult animals were observed. Average observed body weight (BW) of lambs were: BW on birth 3.56 kg, BW after 30 days 12.72 kg and BW on weaning 27.14 kg, while BW of adult sheep was 66.18 kg. Fertility index was 1.31 and average wool production was 3.24 kg. Average lactation lasted for 125 days, with milk production of 102.16 kg, 5.74% protein and 7.12% milk fat. Indigenous breeds are irreplaceable in sustainable systems because they are evolutionary adapted to the conditions in which they are reared. Lipa strain is one of them and due to it's productions in humble conditions it is one of the key for sustainable sheep production.

Biotehnologija u stocarstvu, 2020

The purpose of this study was to investigate oestrus synchronization efficiency and ram maturity ... more The purpose of this study was to investigate oestrus synchronization efficiency and ram maturity effect on fertility of ewes of MIS sheep population during summer season. Research was performed on the experimental sheep farm of the Institute for Animal Husbandry in Belgrade, Serbia. The study included 70 crossbred ewes of MIS sheep population (Pirot Pramenka, Merinolandschaf and Ile de France breed) and 3 Ile de France rams (2 young, sexually unexperienced rams and 1 mature ram). Oestrus was synchronized in all 70 ewes using progestagen impregnated vaginal sponges (30 mg fluorogestone acetate) in combination with 500 IU PMSG. Ewes were mated with rams 48 h later. Obtained fertility and productivity results were as follows: lambing rate 57.14% (40/70), gestation length 147.11, litter size 1.82, stillborn rate 15.07%, birth weight of lambs 4.29 kg and body weight of lambs at 30 days of age 13.07 kg on average. Based on the results obtained in this study it was concluded that presented...

Biotehnologija u stocarstvu, 2020

The most important stressors in our country are unfavourable climatic and nutritional conditions.... more The most important stressors in our country are unfavourable climatic and nutritional conditions. Extreme deviations in climatic and nutritional conditions are immediate stressors for the body of sheep and goats. Appetite in sheep and goats decreases if they are exposed to extremely high ambient temperatures, while cold increases the body's energy needs and leads to the mobilization of fat from body fat and the consequent oxidation of fat and the formation of non-esterified fatty acids. Thyroid activity is reduced when these animals are exposed to high temperatures, and increased when they are exposed to cold. In an environment with high temperatures, blood glucose and cholesterol concentrations decrease due to unsuccessful maintenance of homeostasis. Sheep and goats are naturally kept in a group, which basically protects them from predators. They successfully register the action of new stimuli, especially noise and sudden movements of nearby predators. Early weaning breaks the ...

Biotehnologija u stocarstvu, 2020

Records of female lambs and their parents of the Mis sheep breed have used. All animals are appro... more Records of female lambs and their parents of the Mis sheep breed have used. All animals are approximately have weaned at 90 days of age. Descriptive statistics, paired sample test, paired differences, measures of association, correlations and regression of body weights between female lambs and their parents have done. A complementary least body weights at 30 days and weaning between dams and lambs but utmost weight at 30 days, the lambs were higher while at weaning, the dams had higher weight. It can observe that the averages on body weights the rams were the highest, followed by lambs and the lowest the dams? body weights. The coefficient of determination of R2 varies from low to high, indicating that the lamb's body weight has more influenced by other factors that we have not considered. There were significant correlations between lamb body weight at birth and sire/dam body weight at birth. The results showed highly significant correlations of lamb's body weight at 30 days...

Journal of Agricultural Sciences, Belgrade, 2019

In this review paper, contradictions in modern livestock production as dilemmas of farm animal we... more In this review paper, contradictions in modern livestock production as dilemmas of farm animal welfare are considered. The main dilemma concerns the question of whether extensive production in small farms is generally better than intensive production in large farms. The next dilemma relates to an intensive selection of animals and its impact on the emergence of welfare problems. Another dilemma is related to the two main interconnected problems of pig welfare in individual farrowing pens: the piglet death by crushing and the sows? movement restriction. Similarly, welfare dilemma is the paradox of parent flocks of broiler line breeding that could not be solved until the pressure for genetic advancement in production is required due to the economic efficiency. The next example of the dilemma is the widespread practice of tail docking in piglets in order to reduce the risk of tail biting. Although the tail docking is painful and may cause death, anaesthesia is usually not applied on fa...

Biotehnologija u stocarstvu, 2019

Crossbreeding serves as a predictable and cost-effective method to genetically increase lamb body... more Crossbreeding serves as a predictable and cost-effective method to genetically increase lamb body weight by mating two or more breeds of sheep. The crossing over breed comes to a far greater number of combinations of genes and thus is more likely to express favorable allele carriers of economically important traits. The phenomenon of heterosis has used since the beginning of the last century. However, its genetic basis has remained unclear. From the very beginning of the knowledge of heterosis to the present day, there are several theories, but neither theory able to answer all questions that arise regarding the apparent strength of the F1 generation offspring. Not assert anything about the genetic or molecular phenomenon that causes heterosis. It has been increasingly experimentally confirmed that heterosis is the result of highly complex interactions within the genome as well as between the genome and the environment. In Serbia, some activity of domestic researchers regarding cros...

Biotehnologija u stocarstvu, 2015

Success of crossing depends on the breeds used and the genetic distance among them, as well the c... more Success of crossing depends on the breeds used and the genetic distance among them, as well the combining ability of maternal and individual heterosis to make the proper choice of breeds employed in a crossing system. The aim of this study is to find the effect of genotype and crossing system on early weights and daily gain of lambs. The lambs of purebred Pirot Pramenka ( P) got the lowest body weight at birth, at 30 days, at 60 days and 90 days with a value of 3.65 kg, 9.48 kg, 14.99 kg and 21.96 kg while purebred Wurttemberg attained the highest body weight at birth of 4.48 kg. The lambs of three bred crossing (PxWxF) highest on BW30, BW60 and BW90 days. The results showed a highly significant difference on average daily gain (ADG) among genotypes (P ?0.01) except on the difference between W - PxW of which belongs to the lower border of significant level (P ?0.05). The highest difference on ADG was between P - PxWxF (105.950 g), wherein the lowest difference was between W- PxW (9....

АГРОЗНАЊЕ, 2016

Basic principles of biosecurity plans creation and inplementation were given in this review paper... more Basic principles of biosecurity plans creation and inplementation were given in this review paper. This include goals wanted to be acheived related to specificities of dairy farm technology, sellection of measures that have to be included, order and manner of measures description, inplementation, as well as failures in plan execution. Efficiacy and further sustainibility of biosecurity plans inplementation could be measured through differences between biosecurity level before and after plans application established by questionnaire about biosecurity indicators, such as: 1. isolation of the farm and its organization, 2. quarantine and newly purchased cows policy, 3. visitors policy, 4. attitude towards equipment use, 5. pest control, 6. sanitation efficasy and 7. farm impact on environment. The stakeholders have to define and develop plan to keep potential pathogens for dairy herd health and production in cooperation with the veterinarian and the other professionals advising on organisation and production technology. At least once a year, it is necessary to reconsider the plan and supplemented by new practical experience and scientific knowledge.

Biotehnologija u stocarstvu, 2015

The pure breeds and crossing have an important role in production. It is essential in sheep meat ... more The pure breeds and crossing have an important role in production. It is essential in sheep meat production to maintain the genetic diversity of the adapted breeds, pure breeds and their crosses. Objective of the study is to determine the impact of genotype and sex on growth traits of lambs. Results of the study showed that male of all genotypes were dominant on body weight in all ages (from BWB to BW90). The highest birth weight (BWB) got male of genotype 2 (W). The lowest body weight at birth was the female lambs of genotype 1 (P). Body weights at ages 30, 60 and 90 days, male and female of genotype 4 (PxWxF) were dominant among other genotypes. Genotype 1 (P) of both sexes had the lowest bodyweights in all ages (BWB, BW30, BW60, BW90). The result showed better growth efficiency from males compared with females. The results of fixed factors and its impact on body weights of lambs showed very significant effect of genotype (P<0.01) on body weights of lambs at birth (BWB), ages 3...

Biotehnologija u stocarstvu, 2014

Research was carried out in population of R2 generation Pirot pramenka x Pirot improved sheep dur... more Research was carried out in population of R2 generation Pirot pramenka x Pirot improved sheep during period of three years. Lambs were divided into three groups: I from 2.5 kg to 3.5 kg; II from 3.6 kg to 4.5 kg; III from 4.6 kg to 5.5 kg. Weight of lambs was controlled at birth, with 30, 60 and 90 days of age. Average body weight at birth of the tested lambs was 3.35 kg in the first group, 4.30 kg in the second group and 5.06 kg in the third group. At 30 days of age, the body weight of the lambs was 10.19 kg in the first group, 11.39 kg in the second and 12.49 kg in the third group. All these differences in body weight of lambs at birth were statistically highly significant (P_ 0.01). With 60 days of age, average body weight was 16.48 kg in the first group, 19.01 kg in the second and 20.49 kg in the third group. Differences between groups of lambs at this age were statistically very significant (P_0.01).On the end of experiment at 90 days of lambs age, we have found the following v...

Biotehnologija u stocarstvu, 2014

Three farms of dairy cows (A, B and C) were observed for health disorders of dairy cows and suckl... more Three farms of dairy cows (A, B and C) were observed for health disorders of dairy cows and suckling calves. Farm A is farm with tied system of rearing, with 1100 cows, while farms B and C have 400 and 600 cows kept loose with outdoor pens, respectively. Data regarding welfare criteria of dairy cows (health, feeding, housing and behaviour) were collected and analysed through Protocol of Welfare Quality (2009). Health disorders of dairy cows and suckling calves were collected and statistically analysed by chi-square test (?2 test). Welfare of all of three dairy farms were assessed as acceptable, meaning that provided welfare conditions meet the minimum requirements of animals. Principle of provision of good health was rated as acceptable (?20 points) on farm A, while on farms with loose system (B and C) overall health rated as excellent (?80 points). Occurrence rate of reproductive, locomotor, skin and claws disorders and digestive and systemic disorders of dairy cows and calves up t...

Biotehnologija u stocarstvu, 2012

Efficiency of sheep production is conditioned by fertility. According to some authors number of o... more Efficiency of sheep production is conditioned by fertility. According to some authors number of offspring obtained per lambing is more important than gain of weight. Genetic relationships involving reproductive traits were seldom studied. Reproductive traits have low heritabilities, a discrete phenotypic expression, and are expressed only in sexually mature ewes leading to low selection intensities and long generation intervals. Documentation of realized selection response is also often complicated by the low heritabilities of fertility traits. Existence of a major gene affecting prolificacy had been suggested and at that time there were many sceptics who strongly doubted that a trait as complex as reproduction could be profoundly influenced by a single gene. Major genes affecting prolificacy in sheep was founded. A mutation in the bone morphogenetic protein 15 gene (BMP15, also known as GDF9B) responsible for high prolificacy in Inverdale sheep had been discovered and evidence of s...

Biotehnologija u stocarstvu, 2013

This paper describes a procedure of laparoscopic insemination (LAI) performed in 42 Ile de France... more This paper describes a procedure of laparoscopic insemination (LAI) performed in 42 Ile de France ewes with deep-frozen rams? semen. Frozen semen doses was imported from France, originating from two rams (A and B), and used intermittently in three LAI cycles on different females. The ewes were examined ultrasonographically for pregnancy, two months following insemination and data of lambing were recorded at the end. Total achieved lambing rate was 61.90% (26/42) and total number of lambs was 49 (prolificacy 1.88; 1.16 lambs per sheep included in LAI protocol). Three labs from 2 ewes were stillborn and one dyed at 10th day after lambing. Lambing rates for rams A and B were 53.85% (14/26) and 75.00% (12/16), respectively. Introduction of laparoscopic insemination of sheep with imported deep-frozen semen of top quality rams, gaining technical experience and achieving conception rate over 65% could make this technique acceptable in improving genetic potential of top quality sheep flocks.

Biotehnologija u stocarstvu

The investigation was conducted in population of Mis breed of sheep, divided into three groups. F... more The investigation was conducted in population of Mis breed of sheep, divided into three groups. For reproduction had use rams of Ile de France breed. Induction and synchronization of oestrus was done off-season in October. The percentage of lambing sheep, sheep fertility, and number of lambs acquired per father, sex and birth type of lambs were observed. Ram 1 had a highest number of ewes lambed with an excellent percentage of mating success and highest fertility rate of ewes with differences on fertility rate of 17% (between group of ewes in ram 1 and ram 2), 36% (group of ewes in ram 1 and ram 3) and 19% (group of ewes in ram 2 and ram 3).The highest birth weight were on lambs born single from ram 3, born twins from ram1, triplets of ram 3. For the lambs born quadruplets (unfortunately only in rams 1 and 2 with one lamb of each was alive) the lamb of ram 2 was higher in birth weight. The male and female lambs of ram 3 got the highest birth weight while the female lambs of ram 1 ac...

The purpose of this study was to investigate fertility in the ewes of MIS sheep population follow... more The purpose of this study was to investigate fertility in the ewes of MIS sheep population following synchronized oestrus in anoestrus season and natural oestrus during breeding season. Research was carried out on an experimental sheep farm of the Institute for Animal Husbandry in Belgrade. The study included 76 ewes and 6 rams of MIS sheep population (three breed crosses of Pirot Pramenka, Württemberg and Ile de France breed). In anoestrus season, oestrus was synchronized in 43 ewes using progestagen impregnated vaginal sponges (30 mg fluorogestone acetate) in combination with 750 IU PMSG. During the breeding season, 33 ewes were bred naturally to 6 rams, without the use of exogenous hormones. Teaser rams with marking-harnesses and abdominal aprons were used to detect females in oestrus. Obtained fertility and productivity results in anoestrus and breeding season were as follows: lambing rate 69.77% (30/43) and 100% (33/33) (P<0.05)

The study investigates the possibility of oestrus synchronization in ewes of MIS sheep population... more The study investigates the possibility of oestrus synchronization in ewes of MIS sheep population using prostaglandin (PG) outside the breeding season, serum progesterone concentration for pregnancy diagnosis and effect of hCG (human chorionic gonadotropin) on reproductive parameters. Prostaglandin was used to induce oestrus at the dose of 2.5 ml/ewe, administered intramuscularly in two injections (with 11 days interval). Responsive ewes were bred to rams and were divided into two groups, one of which was administered with hCG at the dose of 300 IU i/m 7th day post mating and the second group which was used as a control. Serum progesterone was measured on the day of prostaglandin administration and 17 days post mating. Oestrus response was 66.67%, lambing rate was 70%, average litter size was 1.7 lambs/ewe and twinning rate was 60%. Administration of hCG 7 days post mating did not improve fertility results. Lambing, prolificacy and twinning rates were higher in control than in hCG g...

On a small closed population of Mis sheep the relationship was studied of the influence of inbree... more On a small closed population of Mis sheep the relationship was studied of the influence of inbreeding on body weight growth from birth to the age of 18 months and sperm DNA fragmentation in rams. Two groups of male lambs were used. First was composed of outbred, while the second of inbred animals with inbreeding coefficient over 25%. Differences in body weight and daily gain related to the presence of inbreeding in the pedigree were not found significant (P>0.05). The mean value of sperm chromatin damage in rams of the outbred group varied from 1.93 to 12.37%, (mean = 7.32%) and in inbred group from 13.76 to 37.67% (mean = 25.23%). Significant difference was identified between the outbred and inbred rams in the mean percentage of sperm damaged (P<0.01).

Large Animal Review, 2020

The investigation was performed on two groups of primiparous and multiparous healthy Alpine dairy... more The investigation was performed on two groups of primiparous and multiparous healthy Alpine dairy goats (25 each) during lactation. Blood samples were collected (jugular venipuncture) 10-15 days before and 10-15 and 30 days after the parturition into BD SST-II Advance (3.5 mL) and BD NaF 3.0 mg Na2EDTA 6.0 mg (2 mL) vacutainers, cooled and centrifuged (1500 r/min, 15 minutes). Glucose, non-esterified fatty acids (NEFA) and β-hydroxybutyrate (BHBA) concentrations in blood sera were determined using A15 automatic spectrophotometric analyzer (Biosystem, Spain). Simultaneously, body condition scoring (BCS) was performed by Villaquiran et al. (2007) method. The obtained data were analyzed by IBM SPSS statistics 21. The glucose concentration inclined to increase in both groups. Differences between glucose levels were significant (p<0.05) 15 days before and 15 days after, as well as 15 and 30 days after the parturition, and very significant (p<0.01) 15 days before and 30 days after t...

The study aim was to know the non-genetic factors and the interaction effect on birth weight of l... more The study aim was to know the non-genetic factors and the interaction effect on birth weight of lambs F1 generation crossed Mis x Ile de France. The data of lambs birth weight (in kg), month of birth, year of birth, season of birth, sex, birth type from progeny (F1 generation) of crossing Mis x Ile de France with a total of 388 lambs born during 2018 to 2019 recorded. The General Linear Model (GLM) procedure was used to analyze the data. The analysis of variance has shown that month of birth significantly affects lambs birth weight (P<.005). Results shows a highly significant effect of year on lambs birth weight (P<.001). The highest mean average birth weight of lambs showed on the second year. Regarding of season, lambs had the highest body weight in spring and winter, and the smallest in autumn but despite the differences in weight, season did not show any significant effect on lambs birth weight (P>.005). Sex of lambs showed no significant effect on lambs birth weight (P>.005). The birth type significantly affects birth weight of lambs (P<.001). The highest body weight are have single, then twins, triplets and quadruplets.

The goal of this review is to discuss the most important issues in the dairy cattle welfare chall... more The goal of this review is to discuss the most important issues in the dairy cattle welfare challenges that facing the dairy industry today and tomorrow, namely dairy cattle welfare indicators and standards and the most significant welfare problems, and to illustrate the role of science in addressing these challenges. It should be noted that producers have always been concerned about the condition of dairy cattle and have tried to ensure that they are healthy and well nourished. In this tradition of the dairy cattle care, good welfare is seen largely as the absence of illness or injury and malnutrition. More recent concerns about dairy cattle welfare have focused on the pain and distress that the cattle might experience as a result of widely accepted management practices, and the possibility that the animals suffer as a result of being kept under apparently inadequate conditions. The evidence suggests that, whilst improvements to the welfare of dairy cows in the developed and develo...

The area of central Serbia is very suitable area for small ruminant production, due to it's hilly... more The area of central Serbia is very suitable area for small ruminant production, due to it's hilly-mountainous region, rich in pastures, and free from heavy use of pesticides, which make it great for organic production. In the territory of central Serbia, representative of autochthonous (indigenous) sheep breeds is pramenka (zackel) with its differentiated strains: Sjenica strain, Svrljig strain, Krivovir strain, Karakachan strain, Pirot strain, Lipa strain and Bardoka (White Metohian strain). Aim of this study was to investigate Lipa strain: number of controlled heads, their productivity parameters and milk parameters. Observed data were processed using the statistical package Statistica for Windows (Stat. Soft Inc.), whereby the basic parameters of descriptive statistics (arithmetic mean, variation coefficient, standard deviation and standard error) were calculated. In this study, total of 840 adult animals were observed. Average observed body weight (BW) of lambs were: BW on birth 3.56 kg, BW after 30 days 12.72 kg and BW on weaning 27.14 kg, while BW of adult sheep was 66.18 kg. Fertility index was 1.31 and average wool production was 3.24 kg. Average lactation lasted for 125 days, with milk production of 102.16 kg, 5.74% protein and 7.12% milk fat. Indigenous breeds are irreplaceable in sustainable systems because they are evolutionary adapted to the conditions in which they are reared. Lipa strain is one of them and due to it's productions in humble conditions it is one of the key for sustainable sheep production.

Biotehnologija u stocarstvu, 2020

The purpose of this study was to investigate oestrus synchronization efficiency and ram maturity ... more The purpose of this study was to investigate oestrus synchronization efficiency and ram maturity effect on fertility of ewes of MIS sheep population during summer season. Research was performed on the experimental sheep farm of the Institute for Animal Husbandry in Belgrade, Serbia. The study included 70 crossbred ewes of MIS sheep population (Pirot Pramenka, Merinolandschaf and Ile de France breed) and 3 Ile de France rams (2 young, sexually unexperienced rams and 1 mature ram). Oestrus was synchronized in all 70 ewes using progestagen impregnated vaginal sponges (30 mg fluorogestone acetate) in combination with 500 IU PMSG. Ewes were mated with rams 48 h later. Obtained fertility and productivity results were as follows: lambing rate 57.14% (40/70), gestation length 147.11, litter size 1.82, stillborn rate 15.07%, birth weight of lambs 4.29 kg and body weight of lambs at 30 days of age 13.07 kg on average. Based on the results obtained in this study it was concluded that presented...

Biotehnologija u stocarstvu, 2020

The most important stressors in our country are unfavourable climatic and nutritional conditions.... more The most important stressors in our country are unfavourable climatic and nutritional conditions. Extreme deviations in climatic and nutritional conditions are immediate stressors for the body of sheep and goats. Appetite in sheep and goats decreases if they are exposed to extremely high ambient temperatures, while cold increases the body's energy needs and leads to the mobilization of fat from body fat and the consequent oxidation of fat and the formation of non-esterified fatty acids. Thyroid activity is reduced when these animals are exposed to high temperatures, and increased when they are exposed to cold. In an environment with high temperatures, blood glucose and cholesterol concentrations decrease due to unsuccessful maintenance of homeostasis. Sheep and goats are naturally kept in a group, which basically protects them from predators. They successfully register the action of new stimuli, especially noise and sudden movements of nearby predators. Early weaning breaks the ...

Biotehnologija u stocarstvu, 2020

Records of female lambs and their parents of the Mis sheep breed have used. All animals are appro... more Records of female lambs and their parents of the Mis sheep breed have used. All animals are approximately have weaned at 90 days of age. Descriptive statistics, paired sample test, paired differences, measures of association, correlations and regression of body weights between female lambs and their parents have done. A complementary least body weights at 30 days and weaning between dams and lambs but utmost weight at 30 days, the lambs were higher while at weaning, the dams had higher weight. It can observe that the averages on body weights the rams were the highest, followed by lambs and the lowest the dams? body weights. The coefficient of determination of R2 varies from low to high, indicating that the lamb's body weight has more influenced by other factors that we have not considered. There were significant correlations between lamb body weight at birth and sire/dam body weight at birth. The results showed highly significant correlations of lamb's body weight at 30 days...

Journal of Agricultural Sciences, Belgrade, 2019

In this review paper, contradictions in modern livestock production as dilemmas of farm animal we... more In this review paper, contradictions in modern livestock production as dilemmas of farm animal welfare are considered. The main dilemma concerns the question of whether extensive production in small farms is generally better than intensive production in large farms. The next dilemma relates to an intensive selection of animals and its impact on the emergence of welfare problems. Another dilemma is related to the two main interconnected problems of pig welfare in individual farrowing pens: the piglet death by crushing and the sows? movement restriction. Similarly, welfare dilemma is the paradox of parent flocks of broiler line breeding that could not be solved until the pressure for genetic advancement in production is required due to the economic efficiency. The next example of the dilemma is the widespread practice of tail docking in piglets in order to reduce the risk of tail biting. Although the tail docking is painful and may cause death, anaesthesia is usually not applied on fa...

Biotehnologija u stocarstvu, 2019

Crossbreeding serves as a predictable and cost-effective method to genetically increase lamb body... more Crossbreeding serves as a predictable and cost-effective method to genetically increase lamb body weight by mating two or more breeds of sheep. The crossing over breed comes to a far greater number of combinations of genes and thus is more likely to express favorable allele carriers of economically important traits. The phenomenon of heterosis has used since the beginning of the last century. However, its genetic basis has remained unclear. From the very beginning of the knowledge of heterosis to the present day, there are several theories, but neither theory able to answer all questions that arise regarding the apparent strength of the F1 generation offspring. Not assert anything about the genetic or molecular phenomenon that causes heterosis. It has been increasingly experimentally confirmed that heterosis is the result of highly complex interactions within the genome as well as between the genome and the environment. In Serbia, some activity of domestic researchers regarding cros...

Biotehnologija u stocarstvu, 2015

Success of crossing depends on the breeds used and the genetic distance among them, as well the c... more Success of crossing depends on the breeds used and the genetic distance among them, as well the combining ability of maternal and individual heterosis to make the proper choice of breeds employed in a crossing system. The aim of this study is to find the effect of genotype and crossing system on early weights and daily gain of lambs. The lambs of purebred Pirot Pramenka ( P) got the lowest body weight at birth, at 30 days, at 60 days and 90 days with a value of 3.65 kg, 9.48 kg, 14.99 kg and 21.96 kg while purebred Wurttemberg attained the highest body weight at birth of 4.48 kg. The lambs of three bred crossing (PxWxF) highest on BW30, BW60 and BW90 days. The results showed a highly significant difference on average daily gain (ADG) among genotypes (P ?0.01) except on the difference between W - PxW of which belongs to the lower border of significant level (P ?0.05). The highest difference on ADG was between P - PxWxF (105.950 g), wherein the lowest difference was between W- PxW (9....

АГРОЗНАЊЕ, 2016

Basic principles of biosecurity plans creation and inplementation were given in this review paper... more Basic principles of biosecurity plans creation and inplementation were given in this review paper. This include goals wanted to be acheived related to specificities of dairy farm technology, sellection of measures that have to be included, order and manner of measures description, inplementation, as well as failures in plan execution. Efficiacy and further sustainibility of biosecurity plans inplementation could be measured through differences between biosecurity level before and after plans application established by questionnaire about biosecurity indicators, such as: 1. isolation of the farm and its organization, 2. quarantine and newly purchased cows policy, 3. visitors policy, 4. attitude towards equipment use, 5. pest control, 6. sanitation efficasy and 7. farm impact on environment. The stakeholders have to define and develop plan to keep potential pathogens for dairy herd health and production in cooperation with the veterinarian and the other professionals advising on organisation and production technology. At least once a year, it is necessary to reconsider the plan and supplemented by new practical experience and scientific knowledge.

Biotehnologija u stocarstvu, 2015

The pure breeds and crossing have an important role in production. It is essential in sheep meat ... more The pure breeds and crossing have an important role in production. It is essential in sheep meat production to maintain the genetic diversity of the adapted breeds, pure breeds and their crosses. Objective of the study is to determine the impact of genotype and sex on growth traits of lambs. Results of the study showed that male of all genotypes were dominant on body weight in all ages (from BWB to BW90). The highest birth weight (BWB) got male of genotype 2 (W). The lowest body weight at birth was the female lambs of genotype 1 (P). Body weights at ages 30, 60 and 90 days, male and female of genotype 4 (PxWxF) were dominant among other genotypes. Genotype 1 (P) of both sexes had the lowest bodyweights in all ages (BWB, BW30, BW60, BW90). The result showed better growth efficiency from males compared with females. The results of fixed factors and its impact on body weights of lambs showed very significant effect of genotype (P<0.01) on body weights of lambs at birth (BWB), ages 3...

Biotehnologija u stocarstvu, 2014

Research was carried out in population of R2 generation Pirot pramenka x Pirot improved sheep dur... more Research was carried out in population of R2 generation Pirot pramenka x Pirot improved sheep during period of three years. Lambs were divided into three groups: I from 2.5 kg to 3.5 kg; II from 3.6 kg to 4.5 kg; III from 4.6 kg to 5.5 kg. Weight of lambs was controlled at birth, with 30, 60 and 90 days of age. Average body weight at birth of the tested lambs was 3.35 kg in the first group, 4.30 kg in the second group and 5.06 kg in the third group. At 30 days of age, the body weight of the lambs was 10.19 kg in the first group, 11.39 kg in the second and 12.49 kg in the third group. All these differences in body weight of lambs at birth were statistically highly significant (P_ 0.01). With 60 days of age, average body weight was 16.48 kg in the first group, 19.01 kg in the second and 20.49 kg in the third group. Differences between groups of lambs at this age were statistically very significant (P_0.01).On the end of experiment at 90 days of lambs age, we have found the following v...

Biotehnologija u stocarstvu, 2014

Three farms of dairy cows (A, B and C) were observed for health disorders of dairy cows and suckl... more Three farms of dairy cows (A, B and C) were observed for health disorders of dairy cows and suckling calves. Farm A is farm with tied system of rearing, with 1100 cows, while farms B and C have 400 and 600 cows kept loose with outdoor pens, respectively. Data regarding welfare criteria of dairy cows (health, feeding, housing and behaviour) were collected and analysed through Protocol of Welfare Quality (2009). Health disorders of dairy cows and suckling calves were collected and statistically analysed by chi-square test (?2 test). Welfare of all of three dairy farms were assessed as acceptable, meaning that provided welfare conditions meet the minimum requirements of animals. Principle of provision of good health was rated as acceptable (?20 points) on farm A, while on farms with loose system (B and C) overall health rated as excellent (?80 points). Occurrence rate of reproductive, locomotor, skin and claws disorders and digestive and systemic disorders of dairy cows and calves up t...

Biotehnologija u stocarstvu, 2012

Efficiency of sheep production is conditioned by fertility. According to some authors number of o... more Efficiency of sheep production is conditioned by fertility. According to some authors number of offspring obtained per lambing is more important than gain of weight. Genetic relationships involving reproductive traits were seldom studied. Reproductive traits have low heritabilities, a discrete phenotypic expression, and are expressed only in sexually mature ewes leading to low selection intensities and long generation intervals. Documentation of realized selection response is also often complicated by the low heritabilities of fertility traits. Existence of a major gene affecting prolificacy had been suggested and at that time there were many sceptics who strongly doubted that a trait as complex as reproduction could be profoundly influenced by a single gene. Major genes affecting prolificacy in sheep was founded. A mutation in the bone morphogenetic protein 15 gene (BMP15, also known as GDF9B) responsible for high prolificacy in Inverdale sheep had been discovered and evidence of s...

Biotehnologija u stocarstvu, 2013

This paper describes a procedure of laparoscopic insemination (LAI) performed in 42 Ile de France... more This paper describes a procedure of laparoscopic insemination (LAI) performed in 42 Ile de France ewes with deep-frozen rams? semen. Frozen semen doses was imported from France, originating from two rams (A and B), and used intermittently in three LAI cycles on different females. The ewes were examined ultrasonographically for pregnancy, two months following insemination and data of lambing were recorded at the end. Total achieved lambing rate was 61.90% (26/42) and total number of lambs was 49 (prolificacy 1.88; 1.16 lambs per sheep included in LAI protocol). Three labs from 2 ewes were stillborn and one dyed at 10th day after lambing. Lambing rates for rams A and B were 53.85% (14/26) and 75.00% (12/16), respectively. Introduction of laparoscopic insemination of sheep with imported deep-frozen semen of top quality rams, gaining technical experience and achieving conception rate over 65% could make this technique acceptable in improving genetic potential of top quality sheep flocks.