The area of central Serbia is very suitable for sheep production, because of it’s hilly and mountainous configuration. Such area is rich in pastures for ruminants. 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 Krivovir strain: number of controlled heads and their part in total sheep population, their productivity parameters and milk parameters. In this study, total of 789 adult animals were observed. Average observed body weight (BW) of lambs were: BW on birth 3.22 kg, BW after 30 days 10.55 kg and BW on weaning 24.99 kg, while BW of adult sheep was 50.52 kg. Fertility index was 1.17 and average wool production was 2.88 kg. Average lactation after weaning lasted for 100 days, with milk production 65.16 kg, 3.91% protein and 6.72% milk fat. Krivovir strain is participating with 0.4% of total number of controlled sheep in central Serbia. Although in small number, this strain is irreplaceable in sustainable systems because they are evolutionary adapted to the conditions in which they are reared and because of their contribution to gene pool and agro-biodiversity.
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 crossbreeding of sheep after
the Second World War has been recorded up to date. It found out that crosses
have a higher body weight than the maternal base in the F1 generation. In
other words, they had better fattening capacity than purebreds. However, the
results are not always in line with expectations due to the influence of
various known and unknown factors. This review paper aims to draw attention
to the phenomenon of heterosis through experience in its application in
Serbia, in the hope that this biological phenomenon would clarify in the
near future by applying modern scientific understandings and technologies.
Quantitative genetic analysis of variability and relationship of lambs body
weight traits in indigenous pirot sheep population are done. The
examined lambs had high variability which very suitable ...for selection on a
larger weight. There is a high and very significant correlation between the
body weight of lambs with 30 and 60 days (.969 **) and the weight with 30
and 90 days (.914 **). There is also a highly significant correlation
between the weights of lambs with 60 and 90 days of age (.904 **). From our
research, we can see that the first month of the lamb's life is very
important for the further development of the body. There is different level
of correlation between weight of lambs. This gives us an idea to say that
many paragenetic factors are crucial for the growth of lambs from birth to
weaning. The coefficient of multiple determination (R2) is 0.845 which means
that 8.45% of the lamb's body weight variance at 90 days is determined by
the variance of the set of predictor variables (PI-60, 30, 1). Each increase
in lamb body weight during the observed periods of age is associated with an
increase in the score of depending variable PI90. In particular, any
increase in lamb body weight at birth by 1 kg is associated with an increase
in lamb body weight from 90 days by 0.238 kg.
This study investigated the possibility of using morphometric measurements to differentiate the autochthonous Serbian White goat breed from Saanen and Balkan goats, which were used as sire and dam ...breeds in its creation. For this purpose, a multivariate discriminant analysis was used. A total of 11 morphometric traits were measured in 98 does of 3 breeds: Saanen (
= 28), Balkan (
= 28), and Serbian White (
= 42), aged 2 to 7 years, in 4 different locations. Univariate analysis of variance revealed a significant difference in body measurements of all three breeds, with Saanen goat being the largest in format and Balkan the smallest. Discriminant analysis extracted six out of eleven tested morphometric traits with the strongest discriminatory power: heart girth, head length, chest depth, head width, pelvic width, and body length. Mahalanobis distances were significant between all three genetic groups. The discriminant function correctly classified 95.24% of the Domestic White goats investigated to their source group. The classification accuracy of the function was cross-validated and indicated an overall success rate of 91.84%. The results of this research showed that there was a clear separation between Serbian White, Saanen, and Balkan goats. The present findings could help a more rapid field assessment of Serbian White goats.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The global demand for sustainable lamb production is increasing due to the need for high-quality meat with minimal environmental impact, making the choice of feeding systems crucial. This study ...investigates the effects of supplemented pasture feeding during the last 60 days of rearing on the meat fatty acid profile, pH value, colour characteristics, and mineral composition of lambs, highlighting the benefits of such feeding systems. Ninety lambs (MIS sheep breed) were divided into three distinct feeding regimes: Group I (alfalfa and concentrate feeding), Group II (white clover Trifolium repens pasture with concentrate supplementation), and Group III (birds’ foot trefoil Lotus corniculatus pasture with concentrate supplementation). The results have shown that supplemented pasture feeding improves the fatty acid profile by increasing n-3 content and desirable fatty acids, while reducing the n-6/n-3 ratio and atherogenic index (p < 0.05), particularly in lambs finished on an L. corniculatus diet. However, forage-supplemented feeding also reduces meat colour lightness and redness (p < 0.05). On the other hand, it enhances the meat’s mineral profile, with higher calcium, selenium, and iron levels, especially in lambs fed L. corniculatus. These findings underscore the benefits of moderate grazing with supplemental concentrates in optimising lamb meat quality. Importantly, they also highlight the potential of forage legumes like T. repens and L. corniculatus to significantly enhance the nutritional profile of lamb meat, offering a promising outlook for the future of sustainable lamb production. Additionally, this research provides valuable insights that could guide the development of future agricultural practices, dietary guidelines, and environmental policies to advance sustainable and nutritious food systems.
The current study aimed to examine the percentage changes of viability sperm
and the activity of the enzymes LDH, ALP, GOT / AST, GPT / ALT in the sperm
plasma of Lacaune rams, before and after ...cryopreservation. For this purpose,
five rams were examined, and two ejaculates were obtained from each ram.
Ejaculates are collected by the method of artificial vagina, during the
insemination campaign. All ejaculates were diluted with a 6AG extender and
frozen by the Cassou?s sequin method. Sperm viability was determined by
eosin and nigrosine smears, and enzyme activity was examined
spectrophotometrically. As a result, the percentage of vital sperm after
cryopreservation decreased by 15% (P ? 0.001). The freezing and thawing
process also reduced the activity of the enzymes LDH, ALP, GOT / AST and GPT
/ ALP. In conclusion, the observed enzymes, in relation to sperm vitality,
could be used as indicators to optimize the protocols for cryopreservation
of ram?s sperm.
The research included a total of 921 lambs, 474 ewes and 8 sjenicke sheep
rams from 4 different farms. The aim of the research was to examine the
influence of the farm, cultivation technology and the ...influence of rams
within the farm on production indicators. Statistical analysis showed that
the body weight of lambs at birth ranged from 3.37 to 4.03 kg (average 3.68
kg), at 30 days from 11.51 to 12.41 kg (average 12.07 kg) and from 90 days
from 27.82 to 29 kg (average 28.65 kg). A statistically highly significant
influence of the farm was determined (P<0.01) on the body weight of lambs in
all three control periods, as well as on the body weight of sheep and on the
fertility of sheep. The influence of the ram on the body weight of the lambs
at birth was statistically very significant within the farm (P<0.01). When
it comes to the percentage share of birth type by farm, farm 1 had the most
singletons (59.13%) both within the farm and in comparison between other
farms, while there were fewer twins (40.87%), and triplets were not
identified. On the other farms, the percentage of twins was the highest, and
triplets were also present, while on farm 4 there were also quadruplets,
lambs born as quadruplets (3.28%).
Gene expression at the phenotypic level varies due to a number of influences
from the environment in which the animals are reared. Ignoring this reality
or due to insufficient knowledge, farmers are ...often disappointed when
choosing a population of sheep when they do not get the production results
that the breed achieves where they bought it. The investigation of the
reproductive and production characteristics of parent herds of Sjenica sheep
was conducted on four farms. In the research, it included a total of 921
lambs and 474 sheep. The influence of sheep body weight on the weight of
lambs at birth within a farm was analyzed. Based on the research conducted
on the sheep population and after the obtained and processed data, we can
state the following: certain differences were found in the fertility of
sheep depending on the farm and body weight. We also perceived that certain
differences in the body weight of the lambs are evident depending on the
weight group of the sheep and the farm where the sheep were raised. All of
the above leads us to the general conclusion that management is extremely
important in sheep farming. If the selection of the breeding population is
carried out correctly and adequate measures of keeping, nutrition and
reproduction are applied, success is guaranteed.
IGFBP-3 is responsible for the multiple effects of growth factors in most
mammalian species and is considered the major transport factor of growth,
used as a marker for different body functions such ...as growth, metabolism,
reproduction, body weight control, immunity, energy balance, and so on.
Considered as a candidate gene, used as a marker for the growth and
production traits as its essential role in the growth and development of the
animals. For the DNA extraction, the blood samples are obtained in the
jugular vein using a 10 ml vacutainer containing EDTA as a coagulant in the
blood collection of each animal Mis breed of sheep (M), Ile de France (F),
and Wurttemberg (W). Isolation of DNA performed using the extraction kit
(Quick DNA kit) with primers set the Forward and Reverse. The body weights
of lambs from birth to 90 days of age, also been calculated. The results of
the agarose gel electrophoresis of PCR amplified IGFBP-3 genes for sheep
populations Wurttemberg (W), Mis (M), and Ile de France (F) had 654 bp. In
our results showed an absence of polymorphism of the IGFBP-3 gene on the
tested sheep populations. The results that there is no polymorphism between
the examined sheep breeds, in terms of IGFBP-3 genes, we were interested
whether there are differences in the body development of lambs of the
mentioned populations because IGFBP-3 is related to the growth of animals.
All three breeds have similar weights and growth dynamics, which could link
to the growth hormone. Analyzing obtained results, we can suggest that
absence of a large difference in the growth of the three breeds of sheep W,
M, F does not have to be related to the absence of polymorphism of the
IGFBP-3 gene but also other genetic and non-genetic factors can affect this
trait. To detect the association between genetic polymorphism in IGFBP-3
genes and body development in lambs, DNA sequencing is required, which will
be the subject of our future research.
Lipska sheep is an autochthonous Serbian population from the group of Pramenka (Zapfel) sheep, bred in the area around Smederevo, Pozarevac and Mladenovac. The average weight of male animals (BW) is ...95 kg and 62 kg of female animals. Other measurements of female animals are: wither height (WH) 74 cm, body length (BL) 78 cm, chest width (CW) 23 cm, chest depth (CD) 40 cm and hearth girth (HG) 91 cm. In the last sixty years, adult female animals gained in average ten kilograms of weight. Other linear measures also increased. The increase is a consequence of better animal management, especially improved diet. Since the reduction of the size of the population, larger animals have dominated, which probably caused the change in the genetic constitution of the breed. Female animals of Lipska sheep are higher compared to the animals of other fifteen Pramenka breeds with the exception of Istrian sheep. The area from which Lipska sheep originates has better soil and richer vegetation compared to the areas of other Pramenka breeds. Partial correlations corrected for weight between individual linear measures were positive, with values between 0.196 and 0.814. Most correlations range between 0.30 and 0.55. Body measurements were studied with ANOVA on females only. The effect of flock influenced all linear measures with the exception of CW, whereas the age of animals had no effect on BL, CW and CD. The increase of individual linear measures was 0.5 to 2.1 mm per kg of BW. The increase of most body measurements from the first to the fifth year was statistically significant (P<0.05).
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