- Informacje o czasopiśmie
- Pierwsze wydanie
- 25 Nov 2011
- Częstotliwość wydawania
- 4 razy w roku
- Otwarty dostęp
Zakres stron: 297 - 313
The consumption of poultry meat and eggs is expected to increase considerably in the nearest future, which creates the demand for new poultry feed ingredients in order to support sustainable intensive production. Moreover, the constant improvement of the genetic potential of poultry has resulted in an increased nutrient density in poultry feeds, which limits the possibility to include low quality feed ingredients. Therefore, the feed industry needs new sources of highly digestible protein with a desirable amino acid composition to substitute other valuable but limited protein sources of animal origin, such as fishmeal. With estimated 1.5 to 3 million species, the class of insects harbours the largest species variety in the world including species providing a high protein and sulphur amino acids content, which can be successfully exploited as feed for poultry. The aim of this paper is to review the present state of knowledge concerning the use of insect protein in poultry nutrition and the possibilities of mass production of insects for the feed industry. There is no doubt that insects have an enormous potential as a source of nutrients (protein) and active substances (polyunsaturated fatty acids, antimicrobial peptides) for poultry. It can be concluded, based on many experimental results, that meals from insects being members of the orders Diptera (black soldier fly, housefly), Coleoptera (mealworms) and Orthoptera (grasshoppers, locust, crickets and katylids), may be successfully used as feed material in poultry diets. However, legislation barriers in the European Union, as well as relatively high costs and limited quantity of produced insects are restrictions in the large-scale use of insect meals in poultry nutrition.
- antimicrobial peptides
- Otwarty dostęp
2. Beneficial Aspects of Inulin Supplementation as a Fructooligosaccharide Prebiotic in Monogastric Animal Nutrition – A Review
Zakres stron: 315 - 331
Inulin is widely used as a prebiotic additive in the nutrition of farm animals and pets. This fructooligosaccharide demonstrates a beneficial effect on host health by stimulating the growth and development of commensal bacterial species inhabiting the large intestine. Used for example in the feeding of piglets, inulin greatly enhances their daily body weight gains and also reduces the risk of anemia (Tako et al., 2008). In poultry, in the case of meat breeds, inulin provides better feed utilization, increases the daily gains and the final carcass weight (Ammerman et al., 1988). In laying hens, it positively stimulates the production of eggs (Chen et al., 2005). The addition of prebiotics in the diet of dogs has a positive effect on the concentration of the end products of sugar and protein fermentation in the colon, thus contributing to the health status and good condition of the animal (Flickinger et al., 2003 b; Middelbos et al., 2007). Moreover, inulin beneficially affects the efficiency of the immune system of the organism (including the anticarcinogenic properties) (Kelly-Quagliana et al., 1998), as well as lipids and the cholesterol metabolism by effectively reducing their concentrations in the blood serum (Grela et al., 2014 a). This paper characterizes inulin as a prebiotic additive in the diet of selected species of monogastric animals. In addition, data about the hypolipidemic and immunostimulatory properties of inulin are presented.
- Otwarty dostęp
Zakres stron: 333 - 345
The occurrence of defective meat depends on factors affecting meat quality at the various stages of meat production. Defective meat has a broad definition and includes any property of meat that will dissatisfy end-users. For consumers the main meat quality features are colour, taste and texture (tenderness and juiciness). For processors and butchers very important are technological quality features: water holding capacity, pH, content of connective tissue, fat and protein. The functionality of defective meat is limited. The risk of incidence of defective meat is a result of the combination of ante-mortem and post-mortem factors. The ante-mortem factors are linked with the procedure at the lairage, the slaughtering factors, such as the method of stunning, and the post-mortem factors, including processing of meat carcasses. The ante-mortem factors such as genotype, gender, breeding conditions, nutrition, transport conditions, stress, weather conditions and the methods of slaughter are considered of primary importance for the quality of pork. It is estimated that 40% of meat defects are due to the procedure at the lairage. The impact of stressors causes a loss of weight of the pigs, contributes, in extreme cases, to the death of porkers, increases the risk of incidence of defective meat. Mixing animals from different herds is the cause of stress which leads to aggression and fights between animals. Limiting the stress factors is essential for improving the quality of pork. The applied stunning method affects the quality of meat. Physical stress during electrical stunning is associated with risk of an accelerated post-mortem glycolysis, contributing to the rapid decrease in pH. In comparison with the electrical method, stunning with carbon dioxide causes less stress in swine. In order to reduce the occurrence of defective meat, bleeding should be carried out as soon as possible directly after stunning. Deterioration of the quality of meat in the production chain can occur at any stage and is most often associated with the lack of compliance with the standards. The studies on the improvement of livestock breeding, transport and marketing carried out over a number of years contributed to the introduction of international standards and, consequently, to the reduction of quality and quantity losses in pork.
- pork meat
- pre-slaughter handling
- slaughter procedures
- Otwarty dostęp
Zakres stron: 347 - 368
The objective of the paper was to demonstrate the possibilities of using Polish native breeds of chickens for the production of meat for its specific quality features in the light of worldwide researches. The object of the analysis was the quality of meat from slow-growing chickens raised in varied housing systems, including capons and poulards. The findings of studies on the quality of poultry meat from native breeds obtained from post-production cockerels and from hens in their post egg-laying stage have shown that there are chances for their use in meat production. Native breed hens can also be used as foundation material for the production of capons, poulards or international mixed breeds for purposes of extensive farming. The body weight of native breed hens, including their muscle build depend on the bird’s genotype, feeding, length of exploitation and farming system. Meat from native breed hens, raised in free-range systems has less fat, but with higher polyunsaturated fatty acids in their meat muscles as well as a healthier ratio of n-6/n-3 PUFA acids. Outdoor free-range access influences the meat colour, i.e., bright coloured breast muscle (L*) as well as increased intensity of red coloration of leg muscles (b*). Caponisation of hens enhances intensified body weight gains along with increased fattening of meat. In comparison with cockerel meat, the meat of capons is more juicy, tender and of better taste, while poulard meat has distinctively favourable sensory values in comparison with broiler chicken meat.
Animal Genetics and Breeding
- Otwarty dostęp
5. MMP-2, TIMP-2, TAZ and MEF2a Transcript Expression in Osteogenic and Adipogenic Differentiation of Porcine Mesenchymal Stem Cells
Zakres stron: 369 - 385
Mesenchymal stem cell (MSC) differentiation is regulated intrinsically by transcription factors and extrinsically by the extracellular matrix. We tested whether matrix metalloproteinase-2 (MMP-2) and its inhibitor TIMP-2, MEF2a and TAZ transcription factors are involved in porcine MSC differentiation towards adipocytes and osteocytes. Flow cytometry and immunofluorescence were used to investigate the expression levels of multipotent cell surface markers CD73 and CD105. Real- time PCR was performed to detect the osteogenic- and adipogenic-specific markers, osteocalcin and aP2, respectively, and to estimate the MMP-2, TIMP-2, MEF2a and TAZ transcript expression levels in three groups of cell, i.e., undifferentiated MSCs, adipocytes (A) and osteocytes (O). We showed that at the transcript level, the differentiation of MSCs towards adipocyte fate may involve MMP-2, TIMP-2 and TAZ. We also show that the differentiation of MSCs toward osteocyte fate may involve TIMP-2, MEF2a and TAZ. Our research provides preliminary data on the possible role of the MMP-2, TIMP-2 and TAZ transcripts in adipogenic differentiation and of the TIMP-2, TAZ and MEF2a transcripts in the osteogenic differentiation of porcine MSCs. We report for the first time the possible involvement of MEF2a in the osteogenesis of porcine MSCs. Our work may provide additional evidence for the MMP-independent function of TIMP-2 during osteogenesis.
- mesenchymal stem cells
- Otwarty dostęp
Zakres stron: 387 - 398
The aim of this study was to estimate genetic parameters and breeding values (BVs) of show jumping horses in the Slovak Republic. The data from show jumping competitions performed in 2004-2013 (The Slovak Equestrian Federation) and data from the Breeding Information Register (The National Stud Farm in Topo’čianky) were used in our work. There were 831 horses (4-21 years old) included in the analysis. The level of competitions ranged from LS (125 cm) to TT (160 cm). Profit of penalty points (PP) and ranking in the competition (R) were analyzed as the measures describing horse performance. The average profit of PP was 5.90±6.28, and mean R was 20.20±16.88. The software package CFC 1.0 was used for computation of inbreeding coefficient (F) in given population. The ratio of inbred animals was 74.49% from 831 investigated animals. The average F value was 0.0068 within inbred population. Input data (profit of PP and R) were not normally distributed, therefore the transformation by Blom formula was made. The height of obstacles was taken into account. The ranking in competition has been nearest to the normal distribution even though the tests of normality have not confirmed it significantly. The heritability coefficient was 0.17 in PP and 0.10 in R. The BVs were estimated for PP and R (BVPP, BVR). The BVs for R were modified to the form of relative breeding values (RBVR). The increase of genetic level of R within population of show jumping horses has been observed in recent years.
- breeding values
- genetic evaluation
- normal distribution
- show jumping
- Otwarty dostęp
7. Associations between Polymorphisms in the DIO3 Gene and Reproductive Traits and Carcass Performance in Pigs
Zakres stron: 399 - 413
Recently, DIO3 gene has been proposed as a candidate gene for litter size in pigs. Moreover, it was shown that polymorphism in this gene is associated with carcass traits. In this study we identified several SNPs within coding sequence of DIO3 by HRM method and performed association study between two polymorphisms and reproductive and carcass traits in pigs bred in Poland. Analysis of 350 pigs of Landrace and Large White breed revealed several significant associations for rs80999359, like period between the second and third parities (2IP)(P<0.0008) in the whole population, period between the third and fourth parities (3IP) (P<0.022), number of piglets born alive (L3NBA) (P<0.0084) and number of piglets at 21 days (L3NB21d) (P<0.0176) at the third parity in Large White as well as period between the second and third parities (2IP) (P<0.0012) in Landrace breed. The second polymorphism (rs80983654) was associated with 1IP (P<0.0218), number of piglets born alive at the fourth parity (L4NBA, P<0.027), number of piglets at 21 day at the fourth litter (L4NB21d, P<0.01), in the whole population, average number of piglets born alive (ANBA, P<0.01250), average number of piglets at 21 day (ANB21d, P<0.009), average interparity period (AIP, P<0.016), age at the first parity (1AP, P<0.003), (1IP, P<0.001, L4NBA, P<0.017, L4NB21d, P<0.005) in Large White breed. In contrast, we have found only few associations between DIO3 polymorphisms and carcass traits. rs80999359 was associated with backfat thickness (p<0.01) while rs80983654 with the weight of ham. Our results suggest that polymorphisms within DIO3 gene may be associated with reproductive traits.
- DIO3 gene
- reproductive traits
- Otwarty dostęp
8.Animal Species Identification through High Resolution Melting Real Time PCR (HRM) of the Mitochondrial 16S rRNA Gene
Zakres stron: 415 - 424
Animal species identification has received growing attention, regarding genetic diversity and food traceability. The objective of this study is to apply a universal primer of part of the mitochondrial 16S rRNA gene analysis using the PCR-RFLP and HRM methods for identification of species origin in cattle, chicken, horse, sheep, pig, buffalo, and goat. PCR product size was 512 bp. The PCR product of 16S rRNA was digested with two restriction enzymes (BclI and MseI); sufficient to easily generate analyzable species-specific restriction profiles that could distinguish the unambiguity of all targeted species. The HRM method successfully identified all species by shape of melting temperature, and proved to be of higher resolution, and a more cost effective, alternative method compared with other identification techniques.
- 16S rRNA gene
- species identification
- Otwarty dostęp
9. Ovine DRB1 Polymorphism and Its Associations with Body Weight, Milk Contents and Immunological Parameters
Zakres stron: 425 - 438
The DRB1 gene is known as a part of the Major Histocompatibility Complex (MHC) with important effects on disease resistance and immunological response in mammals. Single strand conformational polymorphism (SSCP) analysis and direct DNA sequencing methods were employed to study the second exon of DRB1 gene polymorphism in Mehraban and Lori-Bakhtiari sheep, using 155 Mehraban and 167 Lori-Bakhtiari (totally 322) ewes. Eleven different SSCP patterns with 26 SNPs (five new mutations) were found in both breeds. Associations of different genotypes with some traits including body weight, milk contents, milk somatic cell count and some immunological parameters were also studied. The observed genotypes had significant associations (P<0.05) with immunological parameters including serum total protein, α2-globulin, β-globulin, γ-globulin and total globulins and body weight at 3 months of age (weaning). The effects of the genotypes on serum albumin and α1-globulin, body weights at 9 and 12 months of age and milk lactose tended to be significant (P<0.10). The results of the present study indicated that the DRB1 exon 2 is highly polymorphic and could be considered as an important fragment in marker assisted selection, especially for improvement of immunity in sheep.
- DRB1 gene
The Biology, Physiology, Reproduction, and Health
- Otwarty dostęp
10. The Effect of Chemically-Synthesized Silver Nanoparticles on Performance and the Histology and Microbiological Profile of the Jejunum in Chickens
Zakres stron: 439 - 450
The aim of the study was to analyse how per os application of hydrocolloids of silver nanoparticles (22 nm) and lipid-coated nanosilver hydrocolloids (5 nm) affect the microbiological status and morphology of the jejunum of broiler chickens and their growth performance. The experiment was conducted on 60 chickens. The first group was the control. The chickens in group II received a silver nanoparticle hydrocolloid (Ag-nano) at a dose of 5 mg/kg b.w./day. The chickens in group III received a lipid-coated nanosilver hydrocolloid (AgL-nano) at a dose of 5 mg/kg b.w./day. Samples of digesta were taken from the jejunum during dissection and the total numbers of fungi, aerobic bacteria and bacteria of the coli group were determined in the samples. Samples of the jejunum were also collected during dissection to determine the length of the villi and depth of the crypts. The silver nanoparticles had no effect on growth performance or the histological picture of the jejunum. An increase was noted in the total number of aerobic mesophilic bacteria and a decrease in the number of coli group bacteria, which are facultative anaerobes, which indicates that the nanosilver had a selective effect on the microflora of the digestive tract in the chickens.
- Otwarty dostęp
11. Effect of Heat Stress on Metabolic Disorders Prevalence Risk and Milk Production in Holstein Cows in Croatia
Zakres stron: 451 - 461
The objectives were to evaluate the effect of heat stress on daily milk traits (yield, fat and protein content, F/P ratio) as well as to determine the differences in metabolic disorders (acidosis, ketosis) prevalence risk regarding the heat stress conditions. For statistical analysis 1,187,781 test-day records of milk, fat, and protein from 89,030 Holsteins reared on 6,388 farms provided by the Croatian Agricultural Agency, were used. Based on the results it could be concluded that heat stress condition causes decline of daily milk yield and components as well as increase of acidosis risk regardless of the lactation stage and increase of ketosis risk during mid-lactation. The research results point out that the test-day records and environmental measurements collected in regular milk recording could be used as a tool for dairy herd monitoring enabling the early detection of unfavourable environmental conditions and the subclinical disorders. Since environmental conditions significantly affect daily milk yield and components, and consequently F/P ratio, further research with the purpose of detailed formulation of metabolic disease risk in relation to the environmental conditions is needed.
- temperature-humidity index
- test-day records
- prevalence risk
- Otwarty dostęp
12. The Smell of Beer as a Factor Affecting the Emission of Carbon Dioxide by Arion Lusitanicus Auct. Non-Mabille
Zakres stron: 463 - 476
More and more frequently beer is used as an attractant in traps to eliminate the slug Arion lusitanicus auct. non-Mabille. The smell of beer is not indifferent to animals. Hence it is highly probable that it affects the physiological processes in the slug’s body. The aim of our study was to examine whether the smell can induce changes in respiration activity (measured as CO2 emission) of adult individuals of Arion lusitanicus. The results showed that all the tested brands of beer caused an increase in CO2 emission. Furthermore, in all the samples of studied brands of beer, this increase in CO2 emission correlated negatively to the content of the following compounds: acrylic acid N- hydroxysuccinimide ester, decanoic acid, (9Z,12Z)-9,12-octadecadienoic acid, 2-(acetyloxy)-1- [(acetyloxy)methyl]ethyl ester, bicyclo[4,1,0]heptane and ethyl caprylate.
- Arion lusitanicus
- CO2 emission
Animal Nutrition, and Feedstuffs
- Otwarty dostęp
13. Partial Replacement of Soybean with Low-Tannin Faba Bean Varieties (Albus or Amulet): Effects on Growth Traits, Slaughtering Parameters and Meat Quality of Puławska Pigs
Zakres stron: 477 - 487
The study was carried out involving 48 fattening pigs split into 3 groups of equal size: one control (I) and two experimental (II and III). The experimental factor was low-tannin faba bean seeds of the Albus variety (group II) or Amulet variety (group III) introduced to experimental feed mixtures as a partial replacement for soybean meal - the only protein-rich material in the control diet. It was noticed that the partial replacement of soybean meal with faba bean meal had no statistically significant effect on: the daily gains of pigs, feed conversion, meatiness and fattening grades and meat acidity (pH1 and pH24), water holding capacity and muscle colour parameters (L*a*b*). However, the drip loss from longissimus muscles of pigs fed with diets containing low-tannin faba bean was lower and the difference between the group receiving Albus faba bean and the control group was confirmed to be statistically significant (P≤0.05). In the analysed longissimus lumborum muscle, no differences were recorded between the groups in terms of the content of protein, fat, minerals, or saturated and unsaturated fatty acids, including monounsaturated fatty acids. However, it was determined that the muscles of the animals from groups II and III contained more essential unsaturated fatty acids and polyunsaturated fatty acids (P≤0.05 - between groups I and III ). Albus faba bean seeds introduced to the feed mixture had a beneficial effect on the sensory characteristics of the evaluated muscle since, compared to the longissimus lumborum muscle from the control group, it was characterised by significantly (P≤0.05) improved juiciness, tenderness and palatability.
- fattening pigs
- low-tannin faba bean
- growth parameters
- meat quality
- Otwarty dostęp
14. Effect of Dietary Supplementation of Garlic (Allium Sativum) and Turmeric (Curcuma Longa) on Growth Performance, Carcass Traits, Blood Profile and Oxidative Status in Growing Rabbits
Zakres stron: 489 - 505
This study was performed to investigate the effects of dietary supplementation with garlic and turmeric powder as growth promoter agents on performance, carcass traits, serum biochemistry, and antioxidant enzyme activities of growing rabbits. A total of 112 New Zealand White rabbits (NZW) at 5 weeks of age were randomly assigned to seven treatments with four replicates. The dietary treatments consisted of 7 groups as follows; the basal diet as control, phytogenic additives groups were supplemented with 2, 4, and 6 g/kg garlic or turmeric powder added to the basal diet. There were no linear and quadratic differences (P<0.05) in growth performance after garlic or turmeric supplementation at all studied ages. Compared with the control group, supplementation of diets with garlic or turmeric linearly and quadratically elevated immunity biomarkers such as total protein (TP), albumin (AL) and immunoglobulin (IgG) levels and decreased (linearly and quadratically, P<0.05) aspartate aminotransferase (AST), alanine aminotransferase (ALT ), triglyceride (TG) and total cholesterol (TC) levels in rabbit serum. However, TP, AL, globulin (GL), IgG and IgM levels were linearly and quadratically enhanced with increasing turmeric levels versus the control diet. Hepatic superoxide dismutase (SOD), catalase (CAT ) and glutathione peroxidase GSH-Px activities as well as reduced glutathione (GSH) concentrations were linearly and quadratically (P<0.05) improved in garlic or turmeric additives fed groups. While MDA concentration was statistically (linearly, P= 0.022) reduced in comparison with the control group. It could be concluded that garlic or turmeric supplementation (2, 4 and 6 g/kg) did not linearly and quadratically affect growth performance but improved the immunity responses and lowered the lipid profile in blood and lipid peroxidation in liver and increased hepatic antioxidant activity in treated rabbits.
- phytogenic additives
- serum biochemistry
- antioxidant status
- Otwarty dostęp
15. Comparison of the Effect of a Standard Inclusion Level of Inorganic Zinc to Organic Form at Lowered Level on Bone Development in Growing Male Ross Broiler Chickens
Zakres stron: 507 - 519
The purpose of this study was to compare the effect of a standard inclusion level of inorganic zinc to organic form at lowered level on the bone development in growing male Ross 308 chickens, assessed on the basis of mechanical, geometric, and histomorphometric parameters of limb bone, and bone zinc content, as well as hormones of somatotropic axis. A total of 80 one-day-old male Ross broiler chickens were randomly allocated to 2 groups of 40 chickens each. The control group was fed with a corn-soybean meal basal diet providing the recommended zinc amount (100 mg×kg-1) from zinc oxide, and the experimental group was supplemented with glycinate chelate providing 25% of the total requirement of the microelement recommended for Ross 308 broiler chicks. The mechanical and histomorphometric parameters and geometry of tibia were determined as well as the serum concentration of growth hormone, IGF-1, osteocalcin and leptin. The serum concentration of Zn, Cu, Ca, Mg, Fe, P and zinc bone content were determined. The results showed that birds fed with the diet supplemented with organic zinc in the amount of 25% of the recommended amount did not exhibit weight and general growth disorders and had an unchanged concentration of growth hormone, leptin, and IGF-1. The serum concentration of Zn, Cu, Ca, Mg, Fe, P did not differ between groups. The contents of zinc detected in bones in the controls and the group supplemented with the organic source did not differ as well. Although tibial mechanics and geometry remained unchanged, histomorphometry revealed a disproportionately large osteoporotic bone. The changes in tibial trabecular bone as a result of the diet supplemented with glycinate chelate only in 25% of the total requirement of the microelement recommended for Ross 308 broiler chicks seems to be insufficient for tibia development.
- zinc chelate
- Otwarty dostęp
16. Effect of Diet Supplemented with Antioxidants (Selenium, Copper, Vitamins E and C) on Antioxidant Status and Ejaculate Quality of Breeding Boars
Zakres stron: 521 - 532
The aim of the experiment was to determine the effect of selected antioxidants (selenium, copper, vitamins E and C) on the antioxidant status of breeding boar ejaculate and ejaculate quality. In the first control group of boars (n = 10), the amount of antioxidants was not increased in feed. The second experimental group (n = 10) received the addition of selenium (0.5 mg/kg of diet), copper (10 mg/kg of diet), vitamin C (350 mg/kg of diet) and vitamin E (70 mg/kg of diet) in feed. The experiment lasted for 90 days. The addition of antioxidants increased GPx (by 28%), selenium content (by 49%; P<0.05), SOD (by 9%; P<0.05) and level of copper (by 63%; P<0.05) in the experimental group of boars. In the control group, the decrease of sperm motility (by 22%; P<0.05) was found at the end of the experiment. Other measured parameters such as ABTS antioxidant capacity, levels of MDA, metallothionein, zinc, ejaculate volume, concentration, total count of sperm and percentage of abnormal sperm cells were not significantly affected. The above mentioned results show that the addition of antioxidants does not increase the ejaculate quality but their lack can damage the quality indicators of boar ejaculate.
- vitamin E
- vitamin C
- Otwarty dostęp
17. A 22:6 n-3 Rich Supplement Affects the Ruminal Microbial Community and Fermentation and Alters Plasma Metabolites
Zakres stron: 533 - 550
This study investigated the effects of a 22:6 n-3 rich supplement on ruminal fermentation characteristics and microbial changes, and also the effects of a 22:6 n-3 rich supplement on plasma metabolites by using rumen cannulated wether goats in a 4×4 Latin square design. The 22:6 n-3 rich supplement was infused into the rumen of the goats twice daily in equal portions at a rate of 0.0, 2.5, 5.0 and 10.0 g/d [corresponding to 0, 0.4%, 0.8% and 1.5% of diets (dry material base), respectively]. The concentration of NH3-N and total volatile fatty acid (TVFA), and the molar proportions of acetate and butyrate were decreased by the supplement (P<0.001). The supplement decreased diversity of the rumen bacterial community (P<0.01), and reduced the abundance of Ruminococcus flavefaciens, R. albus, Fibrobacter succinogenes and protozoa (P<0.01). However, it increased the abundance of ruminal fungi (P<0.01). The supplement had no influence on the concentration of plasma glucose, HDL-cholesterol, LDL-cholesterol and urea but increased the concentration of triglycerides and total cholesterol (P<0.05). In conclusion, the 22:6 n-3 rich supplement inhibited ruminal fermentation and this was accompanied by the decrease of the abundance of ruminal microbes, and also affected plasma metabolites.
- 22:6 n-3
- ruminal fermentation
- ruminal microbes
Behavior, Well-Being, Production Technology, and Environment
- Otwarty dostęp
18. Estimation of Meat Content in the Carcasses of Young Pigs Based on Performance Testing of Live Animals and Carcass Evaluation
Zakres stron: 551 - 564
The aim of the study was to develop new equations for the estimation of meat percentage in the carcasses of young pigs, based on examination of the current pig population. In addition, new regression equations were constructed to predict the weight of meat in primal cuts. In both cases, the estimates were based on performance testing of live animals and post-slaughter evaluation of carcass traits in these animals. The study was conducted on 654 gilts of six breeds. Performance testing of live animals and carcass evaluation were performed at the Pig Testing Station (SKURTCh). Performance records in live animals included body weight (BW [kg]), age (A [days]), daily weight gain (DG [g/day]), and ultrasonic measurements, using a Piglog 105 ultrasound apparatus: backfat thickness at P2 and P4 and loin eye height P4M (at P4). Then the gilts were slaughtered and, after being chilled for 24 hours at 4°C, the right half-carcass was dissected into primal cuts. These cuts were then subjected to detailed dissection, which provided the basis for determination of the weight of meat in the primal cuts E2 [kg] and meat percentage in the carcass E1 [%]. An array of linear models based on multiple regression was constructed to estimate meat percentage in the carcass [%] and weight of meat in primal cuts [kg]. It was found that the developed linear regression equations for all breeds, which estimated meat content in the carcass based on three variables (classical model: P2, P4 and P4M), were characterised by the following values of standard error of the estimate RSE and correlation coefficient R: for E1[%], RSE=3.33; R=0.63; for E2 [kg], RSE=1.65; R=0.58. The addition to the classical model of a variable describing the breed greatly improved the parameters of the equation predictive of E1 (RSE=3.02; R=0.71). The model predictive of E2 was obtained by the addition of two variables: breed and carcass weight on the day of measurement (RSE=1.37; R=0.73). In general, the present studies indicate that equations estimating the weight of meat in a carcass (E2 [kg]) based on performance testing of live animals are characterised by a much lower value of standard error (RSE) than equations estimating meat percentage in the carcass of the same pigs (E1[%]), including those currently used in practice.
- performance testing in live animals
- carcass evaluation
- meat percentage in carcasses
- weight of meat in cuts
- regression equations
- Otwarty dostęp
19. Improving the Prediction of Methane Production Determined by in Vitro Gas Production Technique for Ruminants
Zakres stron: 565 - 584
Twelve feedstuffs (cereals, fibrous byproducts, protein-rich byproducts and forages) were determined for methane (CH4) production by the in vitro gas production technique (IVGPT) and were correlated with their chemical compositions to predict enteric CH4 originating from these feedstuffs in ruminants. Corn, soybean hull, soybean meal and corn silage generated the highest CH4 production from their respective categories. The average CH4 production of fibrous byproducts (44.6 ml/g DM incubated) was significantly higher than that of cereals (40.3 ml/g DM incubated), forages (33.3 ml/g DM incubated) and protein-rich byproducts (31.0 ml/g DM incubated) after the 48-h incubation (P≤0.05). The highest average total volatile fatty acid (VFA) concentration was determined in cereals (53.6 mM). The acetate to propionate ratio was significantly lower in cereals when compared with other categories of feedstuff (P≤0.05). The correlation analysis showed that in vitro true digestibility (IVTD) positively correlated with the CH4 production in all four categories of feedstuffs (P≤0.05). The neutral detergent fiber (NDF) and acid detergent fiber (ADF) content positively correlated with CH4 production in every category of feedstuffs except cereals. The starch content negatively correlated with CH4 production for fibrous and protein-rich byproducts (P≤0.05), but it positively correlated with CH4 production for forages (P≤0.05). The CH4 production was predicted more accurately by the equations proposed for each category (R2=0.944, 0.876, 0.942 and 0.915 for cereals, fibrous and protein-rich byproducts and forages, respectively) than for the unclassified feedstuffs (R2=0.715). In conclusion, the contribution of individual chemical composition to CH4 production differed depending on the category of feedstuffs. The precision of CH4 prediction could be substantially improved by classifying feedstuffs into categories according to their chemical composition, and selecting the appropriate predictors for each category. Information about the CH4 output of these feedstuffs will be useful in formulating low CH4-producing diets for ruminants.
- in vitro gas production technique
Quality and Safety of Animal Origin Products
- Otwarty dostęp
Zakres stron: 585 - 600
Tenderness is usually associated with the proteolysis occurring in muscles. However, most of the studies concentrate on one muscle only. The aim of this study was to describe the changes in myofibrillar protein percentage proportions during the ageing of 8 bovine muscles. Investigations were conducted on the muscles from different parts of the carcass, from the forequarter: m. pectoralis profundus, m. infraspinatus, m. triceps brachii, m. serratus ventralis, and from the hindquarter: m. biceps femoris, m. semimembranosus, m. semitendinosus and m. longissimus dorsi (thoracis et lumborum). The effect of muscle type was significant for all parameters except for percentage proportions of titin (3000÷3700 kDa), MHC (205 kDa) and protein fractions between <205÷42> kDa. Differences between the muscles varied depending on the analysed proteins and the time of storage. A significant effect of ageing time for titin, nebulin (approx. 800 kDa), proteins of molecular weight of 38 kDa, proteins smaller than 42 kDa and in the range of 3000÷205 kDa, 205÷42 kDa and 38÷20 kDa was observed. The decrease of percentage proportions of titin, nebulin and proteins in the range of 3000÷205 kDa and an increase of protein bands in the range of 38÷20 kDa and proteins below 42 kDa was also observed. During the storage period of beef from the 2nd to the 14th day, the progress of myofibrillar proteolysis was different in each muscle. The changes of tenderness were not related to shear force values. It is probable that the changes in other constituents of meat might influence the tenderness more than those in myofibrillar proteins.
- myofibrillar proteins
- bovine muscles
- Otwarty dostęp
21. Effect of Vacuum Ageing on Instrumental and Sensory Textural Properties of Meat from Uhruska Lambs
Zakres stron: 601 - 609
The objective of the present research was to assess the instrumental and sensory textural attributes of lamb meat depending on the cold storage ageing under vacuum. The research material included two skeletal muscles, i.e. semimembranosus (SM) and rectus femoris (RF) from carcasses of Uhruska lambs. The age of animals ranged from 120 to 135 days. The ageing and muscle influenced significantly shear force and shear energy. However, significantly lower shear force and higher score of tenderness were observed on 7 vs. 2 days of ageing only for SM. The evaluated factors (ageing and muscle) affected slightly and not significantly the parameters of texture profile analysis. The muscle samples after the 7-day ageing showed higher hardness and chewiness. Significant correlation of sensory tenderness with instrumental shear and energy force and springiness was confirmed. The obtained results indicated that vacuum-packed lamb meat during cold storage for 7 days following slaughter develops the sensory attributes, especially tenderness.