Slaughter Characteristics Research Articles

Relationships Among Growth, Carcass Characteristics, and Myf5 Myf6, MyoD, and MyoG Genes Expression Level in Saanen Male Kids with Varying Slaughter Weights

The objective of this study was to determine the relationship between the MRF gene family members and slaughter characteristics in Saanen kids with varying slaughter weights. Twenty male kids of the Turkish Saanen breed were individually fattened for 60 days after weaning under an intensive management system. The kids were divided into two groups: low slaughter weight (L; n = 11; ≤29 kg) and high slaughter weight (H; n = 13; >29) at the end of the fattening. After slaughter, muscle samples from Longissimus-dorsi (LD) and Semitendinosus (ST) muscles were obtained. Carcass characteristics were higher in H than in L kids (p < 0.05). Myogenic Factor 5 gene expression level in the LD muscle of H kids was higher (p < 0.05) than that of L kids. A similar trend was observed regarding Myogenic Factor 6 and Myoblast Determination Factor gene expression levels in the LD muscle (p < 0.05). Also, the Myogenin gene expression level of H kids was higher than that of L kids in both muscles (p < 0.05). There were positive correlations among the slaughter weight, carcass characteristics, and some MRF gene expression levels in both muscles (p < 0.05) that the higher gene expression increases the weight and affects the carcass characteristics. The study results suggest that the difference in slaughter weight at the end of fattening in Saanen kids may be due to the expression level of myogenic regulatory factor (MRF) genes. Fattening performance and MRF genes may have a positive correlation.

Optimizing low-protein diets with edible dock powder: Integrated effects on growth performance, slaughter quality, Organ weights, Muscle quality, and Cecal microbiota in growing Sanhua geese

This study evaluated the effects of supplementing low-protein diets with Edible Dock Powder (EDP) on the growth performance, slaughter traits, serum biochemical parameters, muscle quality, and cecal microbiota of Sanhua geese. A total of 288 healthy, five-week-old Sanhua geese were randomly assigned to six dietary treatments in a 3 × 2 factorial design, with three crude protein levels (16.00 %, 14.50 %, and 13.00 %) and two levels of EDP supplementation (0 % and 2.50 %). Two-way ANOVA and Duncan's multiple range test were used for statistical analysis. EDP supplementation significantly increased average daily gain (ADG) and improved feed-to-gain ratio (F/G) during both growth phases (P<0.01). Lower protein levels significantly reduced average daily feed intake (ADFI) and increased the apparent digestibility of gross energy (ADGE) (P<0.01). EDP significantly improved slaughter rate and eviscerated yield (P<0.05), while reducing liver weight and webbed feet yield (P<0.01). Reduced protein levels decreased serum globulin (GLB) and increased blood urea nitrogen (BUN) levels (P<0.05), with significant interactions between protein levels and EDP supplementation (P<0.05). EDP also significantly altered the cecal microbiota composition, reducing the relative abundance of Actinobacteria, Megamonas, and Collinsella (P<0.05), and affecting KEGG pathways related to protein modification and secondary metabolite degradation (P<0.05). In conclusion, EDP supplementation in low-protein diets improved growth performance, slaughter characteristics, and cecal microbiota, showing potential as a sustainable feed additive for reducing environmental impact and improving the economic efficiency of poultry production.

The effect of herbal mixture supplementation on the fattening, slaughter and selected meat quality parameters of Merino lambs

Abstract The aim of the research was to investigate the effect of herbal additives added to feed concentrate on the slaughter characteristics and meat quality of merino lambs of two Polish breeds – Coloured Merino and Old Type Merino. Throughout the fattening period, the animals received some concentrate mixture ad libitum in the form of granules with 10g/kg or 20g/kg of feed addition of a herbal mixture consisting of fennel – fruit, purple coneflower – herb, minced garlic, and thyme. The content of dry matter, protein, fat, ash, cholesterol, and collagen was determined in meat samples (Musculus quadriceps femoris) collected after slaughter, the fatty acid profile and amino acid content were assessed also. In terms of the examined parameters, both between-breed differences and differences resulting from the diet were observed. Coloured Merino were characterized by higher average daily gains, higher hot and cold carcass weight and higher dressing percentage than Old Type Merino. Meat obtained from lambs of this breed was characterized by a higher level of PUFA-3 and a higher level of most amino acids. Old Type Merino lambs were characterized by a significantly higher Musculus longissimus dorsi (m.l.d.) fat thickness and m.l.d. area. The herbal mixture influenced the fat content in the meat, which was the lowest in the group of lambs that received a larger amount of the herbal supplement. The use of the herbal additive significantly reduced the n-6/n-3 PUFA ratio in the tested meat.

Dietary Effects of Black-Oat-Rich Polyphenols on Production Traits, Metabolic Profile, Antioxidative Status, and Carcass Quality of Fattening Lambs

The study aimed to establish the dietary effects of black oat rich in polyphenols on the production traits, metabolic profile, antioxidant status, and carcass quality of fattening lambs, after weaning. In the BO group, in the feed mixture, common oats replaced the black oat compared to the CO group. The research comprehensively investigated production indicators, blood metabolic profile, antioxidant status, and lamb carcass quality. No significant differences were found in the fattening or slaughter characteristics of lamb carcasses, except for lower pH1 values in BO lamb carcasses. Significant increases in RBC, HCT, and MCV levels as well as TP, ALB, and GLOB concentrations and GPx and SOD activities in the blood of BO lambs were found. The glucose and EOS content as well as the activity of the enzymes ALT and ALP were significantly lower in the blood of the BO group than in the CO group. In the liver, the DPPH activity was significantly higher in the BO lambs compared to the CO lambs. The observed changes in glucose, protein metabolism, and antioxidant status in the blood and tissues of lambs indicate that the use of polyphenol-rich black oats in the diet of lambs under stress conditions is justified.

The Effect of Diets Containing Different Amounts of Chasteberry Seed (Vitex Agnus Castus) On Performance, Carcass, Meat Quality and Stress Parameters of Japanese Quails

Aim of study: To investigate the effects of diets containing different amounts of chasteberry seeds (Vitex agnus- castus L.) on the growing performance, slaughter characteristics, breast meat quality characteristics and stress parameters of Japanese quails (Coturnix coturnix japonica). Area of study: Çakmar, Aydın, Türkiye. Material and methods: A total of 240 one-day-old mixed-sex Japanese quail chicks (9.38 ± 0.02 g) were divided into three treatments with four replicates of 20 birds each in a completely randomized design. The groups were fed a control diet without chasteberry seeds (CS0), a diet containing 25 g/kg chasteberry seeds (CS25), and a diet containing 50 g/kg chasteberry seeds (CS50). The experiment lasted 35 days. Main results: Body weight, body weight gain, and feed intake of the CS50 group were found to be lower than the other groups on days 0-35 (p&lt;0.05). No statistically significant difference was found in carcass and internal organ weights (p&gt;0.05). Except for breast meat water holding capacity, lightness, redness, and hue angle characteristics in females, the effects of diets containing different chasteberry seeds on the meat quality characteristics of male and female quails were not significant (p&gt;0.05). CS25 and CS50 diets caused a statistically significant increase (p&lt;0.05) in glutathione, catalase, and superoxide dismutase values and a statistically significant decrease (p&lt;0.05) in malondialdehyde values in male quail breast meat. Economically, although the lowest feed cost was obtained in the CS50 group, there was no difference in net profit between the groups. Research highlights: The addition of 25 g/kg chasteberry seeds in quail diets can be used easily without any negative effects. However, further studies are needed to determine the effects of different doses of chasteberry seeds on performance and meat quality.

Impacts of rearing-related factors on the slaughter characteristics of broilers

Impacts of rearing-related factors on the slaughter characteristics of broilers

Performance of Boran and Two Strains of Tanzania Short Horn Zebu Cattle Fed on Three Different Diets

A 3x3 factorial experiment was carried out to assess the performance of Boran breed (BRN), Iringa Red (IRR) and Singida White (SWT) strains of cattle fed on three different diets (D1, D2, and D3) under a feedlot condition. The diets contained hominy feed plus molasses (D1 or control), molasses and cassava meal (D2) and rice polishing (D3) as main energy sources. In addition, they contained sunflower seed cake as protein source, minerals and vitamins premix. Fifty-four (54) bulls of equal numbers of each strain, aged between 2 and 2.5 years and average initial weight of 194 ± 12.6 kg were randomly allocated in the three diets and housed in a feedlot structure. They were fed individually with their respective dietary treatments for 80 days, during which data on feed intake and growth performance were recorded. Thereafter 45 bulls with equal number of strains were slaughtered, and carcass characteristics were assessed and gross margins computed. The CP contents (g/kg) in the diets were highest in D2 (155), followed by D1 (141.7) and lowest (130) in D3. There were no significant (P&amp;gt;0.05) interaction effect of diet and breed/strain in all the parameters assessed on performance. Bulls fed on D2 grew faster (0.99 kg/d) and attained greater final weight (269.9 kg) and heavier carcasses (140.8 kg) followed by those fed on D1 with mean values of (0.92 kg/d), (258.1 kg) and (131.5 kg), respectively. The average dressing percentage followed a similar trend, being higher (P&amp;lt;0.05) in bulls fed on D2 (52.4) compared to those on D1 (51.7) and D3 (51.1). The BRN bulls had faster growth rates (1.04 kg/d) followed by the IRR (0.83 g/d), which had similar (P&amp;gt;0.05) average daily gain to that of SWT (0.83 g/d). The final weight of BRN bulls (267.4 kg) was not different (P&amp;gt;0.05) from that of IRR (257.5 kg), which was also found to be similar (P&amp;gt;0.05) to that of SWT (251.2 kg). The hot carcass weights followed similar trend, BRN having carcass weight (138.2 kg) similar (P&amp;gt;0.05) to IRR (130.4 kg), which happened to be not different (P&amp;gt;0.05) from that of SWT (129.3 kg). The mean dressing percentage was higher (P&amp;lt;0.05) for BRN (52.2) than other strains. It is concluded that value of weight gains and slaughter characteristics of Iringa red are comparable to those of Boran, thus for feedlot finishing farmers should be advised to select and use Iringa red bulls to obtain high carcass and large profit.

Effects of microencapsulated essential oils and organic acids preparation on growth performance, slaughter characteristics, nutrient digestibility and intestinal microenvironment of broiler chickens

To develop effective antibiotics alternatives is getting more and more important to poultry healthy production. The study investigated the effects of a microencapsulated essential oils and organic acids preparation (EOA) on growth performance, slaughter performance, nutrient digestibility and intestinal microenvironment of broilers. A total of 624 1-day-old male Arbor Acres broilers were randomly divided into 6 groups including the control group (T1) fed with basal diet, the antibiotic group (T2) supplemented with basal diet with 45 mg/kg bacitracin methylene disalicylate (BMD), and four inclusion levels of EOA-treated groups (T3, T4, T5, T6 groups) chickens given basal diet with 200, 400, 600 and 800 mg EOA/kg of diet, respectively. Results showed that compared with the control, the 200 mg/kg EOA group increased average daily gain (ADG) and average body weight (ABW) during the early stage (P < 0.05). EOA addition decreased crypt depth of the ileum (P < 0.05), but villus height to crypt depth ratio was increased by EOA addition at 200 and 400 mg/kg at d 21 (P < 0.05). Compared with the control, dietary addition EOA at 200, 400 and 600 mg/kg increased the lipase activity in the duodenum at d 21 (P < 0.05). Increased lactic acid bacteria population was found in cecal digesta of the 400 mg/kg EOA group at d 21 (P < 0.05), and higher concentration of butyric acid level was observed in cecal digesta at d 21 and d 42 in the 200 mg/kg EOA group compared with the control (P < 0.05). RT-PCR analysis found that dietary EOA addition decreased the gene expression of IL-1β, COX-2 and TGF-β4 in the ileum at d 21 (P < 0.05), while only the 200 mg/kg EOA increased the gene expression of IL-10, TGF-β4, Claudin-1, ZO-1, CATH-1, CATH-3, AvBD-1, AvBD-9 and AvBD-12 in the ileum at d 42 (P < 0.05) compared with the control. In summary, adding 200 mg/kg and 400 mg/kg of the EOA to the diet could improve the growth performance and intestinal microenvironment through improving intestinal morphology, increasing digestive enzymes activity and cecal lactic acid bacteria abundance and butyric acid content, improving intestinal barrier function as well as maintaining intestinal immune homeostasis. The improving effect induced by EOA addition in the early growth stage was better than that in the later growth stage. Overall, the EOA product might be an effective antibiotic alternative for broiler industry.

Effects of Selenium-enriched Diets on the Growth Performance, Slaughter Characteristics, and Blood Biochemistry of Rhode Island Red Chicken

Effects of Selenium-enriched Diets on the Growth Performance, Slaughter Characteristics, and Blood Biochemistry of Rhode Island Red Chicken

Aspir Yağının Japon Bıldırcınlarında Büyüme Performansı, Et Kalitesi, Karkas Kompozisyonu ve Oksidatif Stres Üzerine Etkileri

This study was conducted to investigate the effects of the addition of SFO (Chartamus tinctorius L.) to dietary of Japanese quail on growth performance, meat quality, carcass composition, and oxidative stress. A total of 40 Japanese quails at ten days of age were used as material and divided into four groups comprising ten birds. The experiment was continued for 35 days. The control group was fed with a diet including no additives, while 0.1%, 0.2%, and 0.3% SFO were added to the feed of the other groups. For this purpose, the effects of SFO on body weight and average daily weight gain of quails, feed consumption (FC) and feed conversion ratio (FCR) of quails, slaughter and carcass piece weights of quails, breast meat quality characteristics, breast meat color characteristics and stress parameters were investigated. There was no significant (P&gt;0.05) difference between the groups in terms of body weight (BW), daily body weight gain (DBWG), daily feed consumption (DFC), FCR, carcass, and slaughter characteristics, color, and pH values. It was found that the addition of SFO significantly reduced total oxidative status (TOS) (P

Metabolomics analysis to interpret changes in physiological and metabolic responses to chronic heat stress in Pekin ducks

Heat stress (HS) is a major environmental threat that affects duck production in subtropical and tropical regions, especially in summer. This study aimed to evaluate the physiological and metabolic responses of Pekin ducks to chronic HS conditions via liquid chromatography-mass spectrometry (LC-MS) using a paired-fed (PF) experimental design. On the basis of equivalent feed intake (HS vs. PF), HS significantly reduced growth performance and the percentage of leg and breast muscles, however, markedly increased the percentage of abdominal fat and breast skin fat. Serum metabolomics results revealed that heat-stressed ducks showed enhanced glycolysis and pentose phosphate pathways, as demonstrated by higher glucose 6-phosphate and 6-phogluconic acid levels in the PF vs. HS comparison. HS decreased hepatic mRNA levels of mitochondrial fatty acid β-oxidation-related genes (MCAD and SCAD) compared to the PF group, resulting in acetylcarnitine accumulation in serum. Moreover, HS elevated the concentrations of serum amino acids and mRNA levels of ubiquitination-related genes (MuRF1 and MAFbx) in the skeletal muscle and amino acid transporter-related genes (SLC1A1 and SLC7A1) and gluconeogenesis-related genes (PCK1 and PCase) in the liver compared to the PF group. When compared to the normal control group (NC), HS further decreased growth performance, but it elevated the abdominal fat rate. However, increased mRNA levels of ubiquitination-related genes and serum amino acid accumulation were not observed in the HS group compared to the NC group, implying that reduced feed intake masked the effect of HS on skeletal muscle breakdown and is a form of protection for the organism. These results suggest that chronic HS induces protein degradation in the skeletal muscle to provide amino acids for hepatic gluconeogenesis to provide sufficient energy, as Pekin ducks under HS conditions failed to efficiently oxidise fatty acids and ketones in the mitochondria, leading to poor growth performance and slaughter characteristics.

MEAT PERFORMANCE, CHEMICAL COMPOSITION AND SENSORY EVALUATION OF MYOCASTOR COYPUS MEAT

The aim of the present study was to evaluate the main slaughter characteristics, chemical composition and sensory properties of meat obtained from 9-month-old male nutria (Myocastor coypus). The animals were killed at the farm, deboned, gutted and frozen. Meat samples were taken from the back, thigh and shoulder. Carcass yield, as well as water content, total protein and crude fat were determined in the laboratory. The energy content was calculated based on the conversion coefficients for protein and fat. The sensory evaluation was performed with a 5-point system for each monitored feature. Average of carcass yield without head was 54.73%. The average of water content varied from 72.80 (shoulder) to 73.68 g.100 g-1 (back), total protein oscillated from 20.78 (shoulder) to 21.65 g.100 g-1 (back), crude fat ranged from 3.65 (back) to 6.10 g.100 g-1 (shoulder). The average energy value was observed to range from 500.17 (back) to 577.91 kJ.100 g-1 (shoulder). The sensory evaluation of the observed meat from the carcass parts was high (4.14 - 4.21 points).

Effect of severe dietary restriction on growth and slaughter characteristics of non-selected growing rabbits

This work was carry out to study the effects of dietary restriction by limiting rabbit access to the feeder on fattening performance. A total of 44 weaned rabbits, of 32-35 days, were randomly divided into 2 groups, the control group (C) fed ad-libitum throughout the fattening period and the group with restricted access to the feed restriction (R). The weekly feeding program of the R group consisted of a restricted access time to the feed trough for 5 days (3h/d) and an ad libitum feed distribution for the weekend during the 5 weeks post-weaning. Two weeks before slaughter (10 to 12 weeks of age), the rabbits from the Group R were fed ad libitum. Results showed lower live weights for Group R at 10 weeks of age (R: 1084.7 g vs. C: 1510.7; p&lt;0.05) but similar at 12 weeks of age (R: 1557.2 g vs. C: 1800.9 g; P&gt;0.05). Different daily feed intakes throughout the fattening period and similar average daily gains (R:16.25 g/d vs. C:22.10 g/d; p&gt;0.05). The feed intake index at the end of fattening was significantly higher in control animals (C:4.15 vs. R:3.85, p=0.001). Carcass yield was similar (C: 68.07% vs. R: 65.70%; p&gt;0.05), peri-renal fat weight was higher in control rabbits (C: 27.17g vs. R: 13.67g; p=0.002).The results of the present study indicate the economic interest of using a feed restriction strategy that could be popularized in local rabbit farms.

Effects of oregano essential oil and capsicum extract supplementation on slaughter characteristics, meat quality, and fatty acid composition of lambs

The aim of this study was to evaluate the effect of oregano essential oil (OEO) and capsicum oleoresin extract (CAO) supplementation on lamb slaughter characteristics, meat quality, and fatty acid composition. In the study, 18 male and 18 female lambs were divided into three equal groups for a 56- day feeding period. The first group was fed the control diet, while the other groups were fed a control diet containing either 300 mg OEO/kg or 300 mg CAO/kg of diet. Feeding OEO or CAO had no effect on the slaughter and carcass quality of the fattening lambs. However, when compared to the female lambs, the male lambs were found to have higher slaughter weights, hot and cold carcass weights, and dressing percentage, while having lower back fat thickness. In addition, OEO substantially increased the intramuscular fat. Dry matter, protein, pH24, meat colour (L*, a*, and b*), drip loss, and cooking loss were not affected by dietary treatment or sex. The addition of OEO or CAO to the diets did not change the meat lipid oxidation or sensory quality characteristics at different storage times. However, meat from the female lambs was found to have thiobarbituric acid reactive substances (TBARS) values lower than that of the meat from the male lambs after 2 d and 4 d of storage. However, the female lamb meat was more preferred in terms of flavour and general acceptance. The ΣMUFA, ΣPUFA, ΣUFA, Σn-6, Σn-3, and Σn-6/Σn-3 contents of the lamb meat were not affected by the dietary treatment. As a result, the inclusion of 300 mg of oregano essential oil/kg of DM in lamb diets is considered appropriate because of its significant contributions to the fat composition of lamb meat.

Carcass composition, meat quality, leg muscle status, and its mRNA expression profile in broilers affected by valgus-varus deformity

Valgus-varus deformity (VVD) is a common leg disease in commercial broilers, which seriously affects animal welfare and causes economic losses. Up to now, most of the studies on VVD have been on skeleton, whereas there are fewer studies on VVD muscle. In this study, carcass composition and meat quality of 35-day-old normal and VVD Cobb broilers assess the effect of VVD on broiler growth. Molecular biology, morphology, and RNA sequencing (RNA-seq) were used to study the difference between normal and VVD gastrocnemius muscle. In comparison with the normal broilers, the breast muscle and leg muscle of the VVD broilers had lower shear force, notably lower crude protein, lower water content, cooking loss, and deeper meat color (P < 0.05). The morphological results showed that the weight of skeletal muscle was significantly higher in the normal broilers than that in the VVD broilers (P < 0.01), the diameter and area of myofibrils in the affected VVD were smaller than in the normal broilers (P < 0.01). Quantitative real-time PCR (qPCR) of gastrocnemius muscle revealed that the expression of myasthenic marker genes, fast myofiber marker genes, and apoptosis-related factors were significantly higher in the VVD broilers than in the normal broilers (P < 0.01). In total, 736 differentially expressed genes (DEGs) were identified firstly in the normal and VVD leg muscle by RNA-seq. Gene ontology (GO) enrichment indicated that these DEGs were mainly involved in the multicellular organismal process and anatomical structure development. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that DEGs are significantly enriched in proteasome. Protein interaction analysis obtained that DEGs with high interaction were proteasome-related coding genes and ubiquitin-related genes, these DEGs were closely associated with muscle atrophy. These show that VVD has an adverse effect on growth characteristics, slaughter characteristics, and meat quality in broilers, which may cause leg muscle atrophy. This study provides some reference values and basis for studying the pathogenesis of VVD in broilers.

Effect of different vaccination programs on production parameters, carcass, leg bones, and digestive system characteristics of broilers

The purpose of the present study was to compare the effects of two commercial vaccination programs using Prevexxion or Vaxxitek vaccines on production parameters, carcass weight and composition, and selected anatomical characteristics of Ross 308 broiler chickens. During the rearing period of broiler chickens, body weights were determined at 1, 10, 35, and 42 d of age, and feed intake and mortality of birds were recorded each day. On d 42 of the rearing period, 20 chickens were selected for dissection, 10 birds from each group. After slaughtering, the weight of the eviscerated carcass and the proportion of carcass elements, the lengths and diameters of individual intestinal segments, the weight of selected internal organs, and the dimensions of the femur and tibia were determined. The Prevexxion vaccination program had a positive significant effect on eviscerated carcass yield, dressing percentage, breast meat, wing and carcass remains content, as well as duodenum length, proventriculus content of slaughter weight and smallest breadth of the corpus of tibia bone. Broiler chickens treated with Prevexxion vaccines had higher European Production Index. The results indicate that Prevexxion vaccines have a more favorable effect on the production performance and slaughter characteristics of Ross 308 broiler chickens than with the use of Vaxxitek vaccines.

Effects of dietary yeast cell wall supplementation on growth performance, intestinal Campylobacter jejuni colonization, innate immune response, villus height, crypt depth, and slaughter characteristics of broiler chickens inoculated with Campylobacter jejuni at d 21

A study was conducted to assess the effects of a dietary yeast cell wall (YCW) with and without a Campylobacter jejuni (CJ) challenge. A total of 2,240-day-old Ross 708 males were randomly assigned within 8 treatments with a 4×2 factorial design, with 4 diets (negative control, positive control, YCW constant dose (400 g/ton), and YCW step-down dose (800/400/200 g/ton in the starter/grower/finisher diets, respectively) and with and without d 21 CJ oral gavage challenge at 5.2×107 CFU/mL. At d 0, 14, 28, and 41 body weights and feed consumption were measured to determine performance. At d 14, 28, and 42, 8 jejunal and ileal histology samples per treatment were collected for villi morphology measurements. At d 22 and 28 (1- and 7-days postinoculation), 24 ileal tissue samples per treatment were collected for relative gene expression analysis. At d 42, 24 cecal content samples per treatment were collected for CJ enumeration. Finally, on d 44, 96 birds per treatment were processed to determine carcass yield and 16 carcass rinses per treatment were collected to determine CJ prevalence after processing. Diet or inoculation did not impact broiler performance (P > 0.05). Limited differences were observed in intestinal morphology, and villus height and crypt depth were different only in the ileum at d 42 (P=0.0280 and P=0.0162, respectively). At d 1 postinoculation, differences between treatments inoculated with CJ and PBS were observed in the expression of avian beta defensin 10 (AvBD10), interleukin 1ß (IL-1ß), and interleukin 10 (IL-10) (P < 0.05). At d 7 postinoculation, expression of AvBD10, IL-1ß, and IL-10 was similar among all treatments (P > 0.05). At d 42, all birds, regardless the inoculation, had similar levels of CJ recovered from cecal contents (P > 0.05). After processing, carcass yield and CJ prevalence postchilling was similar in all treatments (P > 0.05). Overall, under the conditions of this study, the addition of YCW during a CJ challenge did not have an impact in growth performance, innate immune response, cecal colonization, carcass yield, or CJ prevalence after processing.

Prospects for Sustainable Production of the Banija Spotted Pig in Relation to Fattening, Carcass, and Meat Quality Traits: A Preliminary Study

The Banija spotted pig (BS) is a Croatian autochthonous breed that was officially recognised in 2018. The breed remains threatened with extinction and is on its way to establishing a production cycle that will ensure long-term conservation and sustainability. However, there is a general lack of data on the production traits of BS pigs. The aim of this work was therefore to identify the main fattening, carcass and meat quality traits of the BS pig and to assess the suitability of the breed for sustainable pork production. A total of ten pigs were fattened in a semi-free-range production system up to the average final body weight of 162 ± 17.3 kg. At the end of fattening, the growth, carcass and meat quality traits (pH, meat colour and water holding capacity) of the BS pig were determined and the gross margin based on the production of value-added meat products was calculated and compared with other Croatian local pig breeds. The results, which are to be considered preliminary due to the small data set, show that the fattening and slaughter characteristics of the BS pig are satisfactory and consistent with the characteristics of the breed and the husbandry practices adapted to semi-free-range farming. Furthermore, the meat quality showed suitability for processing for most traits, while the calculation of gross profit confirms the advantage of this breed for a well-rounded production cycle compared with related local pig breeds.

Influence of the Level of Sex Hormones in the Blood of Gilts on Slaughter Characteristics and Meat Quality.

The aim of the conducted research was to determine the impact of factors such as sex hormone levels, which vary during gilts' reproductive cycle, on the quality of the obtained meat and slaughter characteristics of the processed gilts. The research material included a population of 60 gilts slaughtered in one of the slaughterhouses located in south-eastern Poland. After the slaughtering operations were completed, the carcasses were weighed at the classification stand. The results of the statistical evaluation of the haematological and biochemical blood parameters of the examined gilts showed that, in the tested blood samples, the concentration of progesterone had a statistically significant impact only on the level of total protein, which was higher in the blood samples of gilts with a low concentration of progesterone. It was found that carcasses of gilts with higher levels of the LH hormone were characterized by a lower meat content index by nearly 3%. It was shown that the concentration of LH affected the post-slaughter temperature of the sirloin and ham muscles. The interpretation of the obtained data was difficult since there seems to be a gap in the literature concerning the dependencies of sex hormone levels in gilts and meat quality.

Effect of multi-enzyme complex and feed form on growth performance, slaughter characteristic, total tract nutrient digestibility, and energy utilization in broiler chickens

This study was conducted to investigate the effect of dietary supplementation of exogenous multi-enzyme complex and feed form on growth performance, slaughter characteristics, nutrient digestibility, phosphorus (P), calcium (Ca), and nitrogen-corrected apparent metabolizable energy (AMEn) utilization in broilers fed corn–soybean meal diets. A total of 312 male one day-old broiler chicks (Ross 308) were allocated to 6 dietary treatment groups with 13 replicates (4 birds each) in a 2×3 factorial arrangement of treatments in a randomized design, which includes mash (M) or pellet (P) diets supplemented with three levels of a multi-enzyme complex (0, 125, or 175 mg/kg) for 42 days. The results indicated that the addition of 175 mg/kg multi-enzyme complex to pelleted feeds (P175) significantly increased (p&lt;0.05) the body weight and feed intake of the broilers during the grower period. The feed conversion ratio (FCR) was significantly improved (p&lt;0.05) by adding the multi-enzyme complex to the pelleted feeds. The feed form * multi-enzyme interaction was significant on d0-21 for BW and FI and all three periods in FCR (p&lt;0.05). Mash feed decreased the European Production Efficiency Factor (EPEF) ratio compared to that of the pelleted feed, and it was observed that EPEF increased (p&lt;0.05) linearly with an increase in the multi-enzyme complex added to both the mash and pelleted feeds. Although there was no difference among the groups regarding the carcass yield and relative organ weights, the gizzard weight increased significantly in chickens fed with mash feeds (p&lt;0.05). In addition, the difference between treatment groups in terms of total tract nutrient digestibility does not differ (p&gt;0.05) significantly, while the highest (p&lt;0.05) AMEn utilization was found in the P175 group. As a result, the pelleted feed form and the increased level of multi-enzyme supplementation improved the performance and efficiency of broiler production.