Fattening Performance Research Articles

Effects of protein grass hay as alternative feed resource on lamb's fattening performance and meat quality

Protein grass hay (PGH) was used as a new feed source for lambs to study its effect on fattening performance and meat quality. Fifty-six male lambs were allotted to four experimental groups and fed for eight weeks either alfalfa hay (AH)-based diet (control) or diets in which AH was replaced with 33 %, 66 %, or 99 % PGH. The inclusion of PGH did not affect final body weight, dry matter intake, average daily gain, feed conversion ratio, or carcass weight. Moreover, substituting AH with PGH at any level did not influence the ruminal fermentation or serum biochemical parameters, meat color, water holding capacity, shear force, or amino acid profile. However, relative liver weight was increased with 66 % substitutions. Furthermore, replacing 99 % AH with PGH decreased the meat's pH at 24 h. Higher levels of C18:3n-3, C20:5n-3, and total n-3 PUFA and a lower ratio of n-6: n-3 PUFA were also observed in meat from lambs fed PGH at 99 %. These findings suggest that PGH could be incorporated into the lamb's diet up to 99 % without compromising fattening performance and body health while improving their meat n-3 PUFA deposition.

Effectiveness of coconut meat waste in feed intake, digestion and protein retention in goats

The objective of the experiment was to determine the proportion of coconut meat waste on feed consumption, nutrient digestibility and nitrogen retention of goats. The experiment was conducted using a Latin square design on 4 male Bach Thao goat (16.2±2.93 kg). Treatments were 4 levels of coconut meat waste (CMW) at 0, 5, 10 and 15% in basal diet of rice distillers’ by-product, cabbage waste, Operculina turpethum vines, urea and premix. Results indicated that dry matter intake per body weight tended to increase from CMW0 to CMW5 treatment but it was gradually reduced from CMW5 to CMW10 and CMW5 treatments (3.34; 3.50; 3.46 and 3.28, respectively). The ME consumption was higher at supplemented treatments coconut meat waste compared to CMW0 treatment. The nutrient digestibility (%) was gradually increased from CMW0 to CMW15 treatment. Similarly, digestive nutrients tended to increase with increasing coconut meat waste in the diet. The nitrogen retention was numerically lower for the CMW5, CMW10 and CMW15 treatments compared to CMW0, while daily weight gain was not different among treatments. In conclusion, 10% coconut meat waste could be used as an additional source of dietary regimen in goats, without negative effects on animal fattening performance.

Effect of prudent use of antimicrobials in the early phase of infection in pigs on the performance and meat quality of fattening pigs

The presented study was a part of the ThermoEye project. The study examined the effect of prudent antibiotic treatment in response to illness on the fattening performance, slaughter traits, and meat quality of the pig fatteners. Pigs were divided into an experimental group – EXP and a control – CON. In both groups, the body temperature was monitored, and diseases were confirmed by a veterinarian. In the EXP group, metaphylaxis was used in each case of confirmed disease. The EXP fatteners had greater slaughter weight (by 4.7 kg) and meatiness (by 2.1 percentage points) compared to the CON pigs. The pH in pork was lower in EXP compared to CON pigs. The longissimus thoracis et lumborum of EXP pigs was characterised by a lower cooking loss (28.30 vs. 30.45%) and yellower colour compared to the CON group. Among the amino acids, only the content of histidine (by 5.2%; P < 0.01) and tyrosine (by 7.2%; P < 0.01) was significantly greater in the meat of the CON group compared to EXP, with no effect of sex noted. The content of SFA (by 14.6%; P < 0.05), UFA (by 15.6%; P < 0.05), MUFA (by 17.8%; P < 0.05), MCFA (by 14.1%; P < 0.05), and LCFA (by 15.6%; P < 0.05) was also greater in CON compared to EXP meat. In conclusion, automated monitoring of pig body temperature during the fattening period enables more precise, prudent treatment and effective animal health control while reducing costs due to disease losses and pharmacotherapy. It allows optimal production and affects meat quality.

The Effect of Birth Weight on Fattening Performance, Meat Quality, and Muscle Fibre Characteristics in Lambs of the Karayaka Native Breed.

This investigation aimed to assess the influence of birth weight on post-weaning fattening performance, meat quality, muscle fibre characteristics, and carcass traits in Karayaka lambs. The study categorized the lambs into three distinct groups based on birth weight: low birth weight (LBW), medium birth weight (MBW), and high birth weight (HBW). Throughout the fattening phase, the lambs were given ad libitum access to food and water, culminating in the slaughter at the end of the study. Following slaughter, warm and cold carcasses were weighted, and specific muscles (longissimus thoracis et lumborum [LTL], semitendinosus [ST], and semimembranosus [SM]) were isolated for the evaluation of muscle weights, muscle fibre types (Type I, Type IIA, and Type IIB), and muscle fibre numbers. Carcass characteristics were also determined, including eye muscle (LTL) fat, loin thickness, and meat quality characteristics, such as pH, colour, texture, cooking loss, and water-holding capacity. The statistical analysis revealed highly significant differences among the experimental groups concerning muscle weights and warm and cold carcass weights (p < 0.01), with the lambs in the HBW group exhibiting a notably higher carcass yield (in females: 45.65 ± 1.34% and in males: 46.18 ± 0.77%) and LTL, ST, and SM (except for female lambs) muscle weights than the lambs in LBW group (p < 0.01). However, apart from the texture of LTL and ST muscles, no significant differences in meat quality parameters were observed among the treatment groups (p > 0.05). Notably, the birth weight of lambs did not impart a discernible effect on the total number and metabolic activity of muscle fibres in LTL, ST, and SM muscles. Nonetheless, a noteworthy distinction in the fibre area of Type I fibres in the LTL muscle of male lambs (LBW: 30.4 ± 8.9, MBW: 29.1 ± 7.3 and HBW; 77.3 ± 15.4) and in the ST muscle of female lambs (LBW: 44.1 ± 8.1, MBW: 38.8 ± 7.7 and HBW: 36.9 ± 7.1) were evident among the birth weight groups (p < 0.05). The study also found that the mean fat thickness values of eye muscles in Karayaka lambs, as obtained by ultrasonic tests, were below the typical range for sheep. In synthesis, the outcomes of this study underscore the considerable impact of birth weight on slaughtered and carcass weights, emphasizing the positive association between higher birth weights and enhanced carcass yield. Remarkably, despite these pronounced effects on carcass traits, the birth weight did not demonstrate a statistically significant influence on meat quality or overall muscle fibre characteristics, except for the area of Type I fibres in the LTL muscle. This nuanced understanding contributes valuable insights into the intricate relationship between birth weight and various physiological and carcass parameters in Karayaka lambs undergoing post-weaning fattening.

Simulation of dual-purpose chicken breeding programs implementing gene editing

BackgroundIn spite of being controversial and raising ethical concerns, the application of gene editing is more likely to be accepted when it contributes to improving animal welfare. One of the animal welfare and ethical issues in chicken breeding is chick culling, the killing of the male layer chicks after hatching due to the poor fattening performance. Although establishing dual-purpose chicken lines could solve this problem, unfavorable genetic correlations between egg and meat production traits hindered their competitiveness. Although it is also controversial in ethical terms, gene editing may accelerate genetic progress in dual-purpose chicken and alleviate the ethical concerns from chick culling.ResultsThe simulation compared the utility improvement in dual-purpose use under two breeding schemes: one consisting in the improvement of the laying hens, and the second in the improvement of a synthetic line obtained from a layer broiler cross. In each breeding scheme, the breeding programs were simulated with and without gene editing. Polygenic breeding values and 500 simulated quantitative trait loci (QTL) with different levels of pleiotropy caused negative correlations between egg production, meat production, and overall health. The results of the simulation demonstrated that genetic gain could be accelerated by at most 81% for several generations if gene editing was used. The actual increase in genetic gain depended on the number of single nucleotide polymorphisms (SNPs) being edited per animal. The rate of genetic improvement became equal in scenarios with and without gene editing after 20 generations. This is because the remaining segregating QTL had small effects and their edition would have negative overall health effects from potential off-target edits. Although gene editing can improve genetic gain in quantitative traits, it can only be recommended as long as QTL with reasonable effect sizes are segregating and detectable.ConclusionsThis simulation demonstrates the potential of gene editing to accelerate the simultaneous improvement of negatively correlated traits. When the risk of negative consequences from gene editing persists, the number of SNPs to be edited should be chosen carefully to obtain the optimal genetic gain.

O efeito no desempenho de engorda e nas características de carcaça da adição de vinagre de alcachofra à água de bebida de frangos de corte

ABSTRACTS This study was carried out to investigate the effects of adding artichoke vinegar to the drinking water of broilers on their fattening performance and carcass characteristics. In the experiment, 204-day old broiler chickens were used, and the study was continued for 42 days. In the study, 4 different groups were formed, one of which was the control group, and the other 3 were different doses of vinegar (0.5%, 1.0 and 1.5). The experiment was carried out in 3 replications and 17 birds were included in each replication. During the fattening period, the live weight, feed consumption, vinegar water consumption and slaughter weight of the chickens were measured. After slaughter, characteristics such as hot carcass weight, hot carcass yield, internal organ weights and abdominal fat weights were determined. According to the results obtained, in the 0-6 weeks period, the daily average live weight gain, daily average feed intake, total feed intake, feed conversion ratio, average daily water intake and total water intake of the broilers were significantly higher than the values obtained in the treatments with vinegar (P&lt;0.05, P&lt;0.01). It was determined that the groups showed significant differences in terms of traits such as abdominal fat weight and percentage, liver weight, heart weight and percentage, and kidney weight and percentage. As a result, it can be said that the artichoke vinegar added to the drinking water of broilers has significant effects on some performance characteristics and has the best effect when used at 1.5% level.

Optimization Strategies to Adapt Sheep Breeding Programs to Pasture-Based Production Environments: A Simulation Study.

Strong differences between the selection (indoor fattening) and production environment (pasture fattening) are expected to reduce genetic gain due to possible genotype-by-environment interactions (G × E). To investigate how to adapt a sheep breeding program to a pasture-based production environment, different scenarios were simulated for the German Merino sheep population using the R package Modular Breeding Program Simulator (MoBPS). All relevant selection steps and a multivariate pedigree-based BLUP breeding value estimation were included. The reference scenario included progeny testing at stations to evaluate the fattening performance and carcass traits. It was compared to alternative scenarios varying in the progeny testing scheme for fattening traits (station and/or field). The total merit index (TMI) set pasture-based lamb fattening as a breeding goal, i.e., field fattening traits were weighted. Regarding the TMI, the scenario with progeny testing both in the field and on station led to a significant increase in genetic gain compared with the reference scenario. Regarding fattening traits, genetic gain was significantly increased in the alternative scenarios in which field progeny testing was performed. In the presence of G × E, the study showed that the selection environment should match the production environment (pasture) to avoid losses in genetic gain. As most breeding goals also contain traits not recordable in field testing, the combination of both field and station testing is required to maximize genetic gain.

Stall-Feeding of Sheep on Restricted Grazing: Effects on Performance and Serum Metabolites, Ruminal Fermentation, and Fecal Microbiota.

This study investigated the effects of three feeding systems, indoor feeding (CONT), indoor feeding with time-restricted grazing artificial pasture (4 h/day, G4H), and indoor feeding with an eight-hour daily grazing artificial pasture (G8H), on the growth performance, serum metabolites, ruminal fermentation, and fecal microbiota composition of lambs. Average daily gain showed a tendency (p = 0.081) to be higher for the G4H group compared with the CONT group. Moreover, feeding systems did not have a significant effect on most of the serum biochemical indicators in lambs. Concentrations of serum glutathione peroxidase and immunoglobulins (IgA, gG, and IgM) were significantly lower (p < 0.01) in the CONT group. Additionally, a tendency towards higher levels of volatile fatty acids, acetate, and butyrate was found in animals of the G4H group compared to the CONT group. Furthermore, fecal microbiota composition was altered in G4H and G8H groups, resulting in the increased relative abundance of Firmicutes and Ruminococcaceae UCG-005, as well as the decreased relative abundance of Ruminobacter compared with the CONT group. Overall, these results suggest that indoor feeding with restricted grazing time does not significantly affect fattening performance or rumen fermentation but enhances antioxidation and immune function activity and also alters fecal microbiota composition.

Fish oil supplementation as an omega-3 fatty acid source during gestation: effects on the performance of weaned male goat kids.

The aim of this study was to evaluate the effects of fish oil supplementation, as an omega-3 fatty acids source, to ration of does in the different periods of pregnancy on the fattening performance of kids after weaning. Eighty German Fawn × Hair crossbred does were randomly divided into two groups; half were given fish oil in the first half of pregnancy (FO group), while the other half were given saturated fat (PF (control) group). Then, the goats in the FO and PF groups were randomly divided into two subgroups, and half of the goats were fed fish oil during the second half of pregnancy (FO-FO and FO-PF groups), while the other half was fed saturated fat (PF-FO and PF-PF groups). Thus, study groups of kids were formed according to the nutrition program of the does described above. Forty-seven male kids (84.6 ± 2.44 days old; 14.5 ± 3.09 kg live weight, mean ± standard deviation) were fed for 56 days after weaning, and their weight, feed consumption, serum biochemical parameters, carcass performance, and meat quality characteristics were evaluated. Maternal nutrition significantly affected live weight gain and serum AST, glucose, total protein, and globulin concentrations (P ≤ 0.050). The live weight gain of kids in the PF-PF and PF-FO groups was higher than that in the FO-FO and FO-PF groups. Maternal nutrition tended to affect the hot and cold carcass weights of male kids (P = 0.078 and P = 0.084, respectively). In conclusion, fish oil supplementation during gestation could negatively affect the fattening performance of kids after weaning, especially the daily live weight gain, although it tended to positively affect hot and cold carcass weights.

Fattening performance, nutrient digestibility, and carcass traits of two fat-tailed sheep breeds.

Fat-tailed sheep breeds are the most widespread types of sheep in the Middle East. They are hardy and have acceptable growth and carcass traits. The purpose of this study is to compare the fattening performance, nutrient digestibility, and carcass characteristics of two fat-tailed sheep breeds, Awassi and Najdi. Thirty single-born Awassi and Najdi male lambs (15 lambs per breed) were examined for fattening and carcass characteristics. The study lasted 70days (10days adaptation period and 60days for collecting the data). Feed consumption was monitored daily, and the body weight of lambs was recorded upon arrival to the trial area and biweekly afterward. Lambs were slaughtered at the end of the study to assess carcass and meat quality characteristics. Nitrogen intake and retained nitrogen were higher (P < 0.05) for Najdi lambs. The digestibility of nutrients was comparable between the two genetic groups. Initial body weight, final body weight, average daily gain, and dry matter intake were not affected (P > 0.05) by the lamb's breed. Furthermore, the feed-to-gain ratio, hot and cold carcass weights, and dressing percentage were not affected by breed type (P > 0.05). Breed type has no influence on the shoulder, loin, and rack percentages of the lamb. Moreover, meat quality traits were not affected by the lamb's breed (P > 0.05). In the dissected leg cut, no differences in the leg component were found among the two breed types (P > 0.05). Results of this study reveal that nitrogen intake and retained nitrogen were higher for Najdi lambs, but this was not reflected in fattening performance and carcass traits.

Effects of heat stress on fattening performance, carcass traits, oxidant/antioxidant status, and hepatic heat shock protein 70 levels in different plumage colors of Japanese quail (Coturnix coturnix japonica).

The aim of this study was to investigate the impact of heat stress on production performance and oxidative stress in different plumage colors of Japanese quail. For this purpose, a total of 100 birds were used in this study. The 25 birds belonged to Wild-type (n=25, grey), Tuxedo (n=25, black), Golden (n=25, yellow) and Recessive white (n=25). The birds were reared for 42 days in an environmentally controlled room at 39°C and relative humidity of 60-65%. The body weight, body weight gain (g/bird/day), and feed conversion ratio were not different between the groups (p>0.05). However, the feed intake (g/bird/day) of the Wild-type had a higher value than the Tuxedo (black) group counterparts between 15 and 21 days different (p⟨0.05). There was no significant effect of heat stress on the carcass traits (p>0.05). Spleen weights were different between the groups (p⟨0.05). The yellow group had the highest spleen weight. The highest MDA level was found in the Recessive White variety, followed by Wild-type (grey), Golden (yellow) and Tuxedo (black), respectively. However, there were no statistical differences amongst the groups (p>0.05). There was also no statistical significance in glutathione (GSH) and superoxide dismutase (SOD) levels (p>0.05). The heat shock protein 70 kDa (HSP70) level was significantly different between the groups (p⟨0.001). The highest percentage was observed in the Golden (5.06%) and the lowest in the White (1.43%) variety. There was no superior color variety of Japanese quail regarding fattening performance and carcass traits. It is conceivable that when considering the stress response of the different colors, the Golden group is more sensitive to stress due to the hepatic and cellular level of HSP70.

Comparison of reproductive performance, live weight, survivability, and fleece characteristics of indoor-raised Central Anatolian Merino and Malya sheep

This study was conducted to compare Central Anatolian Merino (CAM) and Malya sheep under intensive conditions in terms of reproductive traits, birth and weaning weights, fattening performance, and some fleece characteristics. In this study, 840 CAM and 194 Malya ewes were used for the comparison of reproductive performance, whereas 740 and 211 lambs were used to compare growth traits between the two breeds. Additionally, the fattening performance of 61 CAM and 68 Malya lambs were compared. Finally, for the [...]

Lamb development traits and phenotypic correlations between different body measurements and fattening performance characteristics in Awassi sheep

Aims: The aim of this study was to investigate lamb growth from birth to weaning and the relationships between different body measurements with fattening characteristics for Awassi sheep lambs.Methods and Results: This study was carried out with Awassi sheep lambs reared in Kilis province of Türkiye. Lambs are weaned at 60 days of age. Twenty head of male lambs, with similar weaning weights and approximately 3 months of age (between 80-95 days) were selected in order to determine the fattening performance of the lambs born in the flock. The lambs were weighed at 14-day intervals in the fattening period, which continued for 70 days. The lambs consumed the concentrate containing 16% crude protein and 2600 kcal ME and alfalfa hay as ad lib. Birth and weaning weights of the lambs were determined as 4.29±0.061 kg and 12.93±0.209 kg, respectively. The daily weight gain and feed conversion ratio were calculated as 241.0±9.83 g and 5.4, which continued for 70 days of fattening period. Conclusions: Positive and significant phenotypic correlations were determined between the live weights of the dams and the birth weights of the lambs. In addition, a positive and high phenotypic correlation was determined between body length and live weight at the end of the fattening for the lambs.Significance and Impact of the Study: At the end of the study, it was determined that the birth season affects the development of the lambs, there is a positive relationship between body length and final fattening weight for the lambs. For this reason, spring births in Awassi sheep production can be recommended to the breeders. In addition, it may be recommended to consider body length for choosing fattening material.

Improving the functional value of meat quality by feeding with protected fat supplementation in Morkaraman lambs

ABSTRACT This study investigated the effect of feeding different levels of protected fat (calcium soaps of tallow) on fattening performance, carcass characteristics, meat quality, fatty acid composition of Longissimus Thoracis (LT) muscle and economic evaluation of 45 fat-tailed Morkaraman male lambs. The lambs were randomly divided into three groups including a control diet without protected fat (CON), supplemented with 2% protected fat (group PF2), and supplemented with 4% protected fat (group PF4) during the fattening period. Eight lambs randomly selected from each group were slaughtered to determine carcass characteristics and meat quality. Supplementing protected fat significantly improved the fattening performance and carcass characteristics (p<0.05). The groups were similar in terms of pH, colour, ether extract, dry matter and sensory evaluations, except for the crude protein of group PF2. Myristic acid and stearic acid (p<0.05), which are saturated fatty acids (SFA), were decreased with the supplementation of protected fat, while palmitic acid was increased (p<0.01). The fattening with protected fat had a highly significant positive effect on important unsaturated fatty acids such as oleic acid (p<0.01) and resulted in an increase of approximately 91% in the conjugated linoleic acid (CLA) (p<0.05). SFA was significantly decreased, and health indicators were improved (p<0.01). In conclusion, the supplementation of protected fat had a positive effect on fattening performance, carcass traits, chemical, sensory properties and economic evaluation.

The Effects of Breeder Age and Hatching Period on Fattening Performance and Carcass Characteristics in Geese

This study was carried out to determine the effects of breeding age and hatching period on fattening performance and slaughter characteristics in geese. For this purpose, were fattened 270 geese obtained from three different ages of geese breeder (one, two, three years old), and 54 of them were slaughtered at the age of 16 weeks to evaluate their carcass characteristics The values of 81.06, 94.15, and 93.37 g for hatching weights, 5275.27, 5590.25, and 5604.90 g for body weights at the 16th week, 24.57, 25.53, and 25.75 kg for total feed consumption and 3592.00, 3814.98, and 3850.6 g for warm carcass weight were determined in the evaluation of carcass characteristics of geese from obtained one, two and three years old breeder geese, respectively. The results of the present study suggested that breeder age had statistically significant effects on hatching weight (P&lt;0.001), body weight (P&lt;0.05), total feed consumption (P&lt;0.01), warm and cold carcass weights (P&lt;0.01). The hatching weights of 92.81 and 86.24 g, total feed consumption values of 24.91 and 25.66 kg, feed conversion ratios of 4.57 and 4.80 were calculated in the first and second periods. The difference in the hatching period was detected to have statistically significant effects on hatching weights (P&lt;0.001), feed consumption (P&lt;0.05), feed conversion ratio (P&lt;0.01), and abdominal fat weights (P&lt;0.001). In addition, it was suggested that seasonal variations could create differences in themselves depending on the stages of the growth and development process.

The use of metabolomics tools in the evaluation of the fattening performance of lambs

This study aimed to determine the metabolomic characteristics associated with the fattening performance of the Awassi lamb breed under intensive fattening for 90 days. Twenty-four lambs were used in the research. The lambs were divided into two groups according to their fattening performance (good fattening performance, n = 12, and poor fattening performance, n = 12), and their metabolomic properties were evaluated. The differences between the two research groups in the amino acids of alloisoleucine, aspartic acid, histidine, hydroxylysine, isoleucine, lysine, methionine, phenylalanine, tryptophan, valine, and 1-methylhistidine were found to be statistically significant (P ≤ 0.001). Moderately significant negative correlations were found between daily concentrate feed intake and 3-methylhistidine (r = −0.469; P = 0.021), hydroxylysine (r = −0.408; P = 0.048), and serotonin (r= −0.467; P = 0.021); as well as between the average daily weight gain (ADWG) and alloisoleucine (r = −0.528; P = 0.008), 3-methylhistidine (r = −0.440; P = 0.032), and hydroxylysine (r = −0.577; P = 0.003). A moderate positive correlation was found between hydroxyisovalerylcarnitine and ADWG (r = 0.476; P = 0.019), and a negative correlation was found between hydroxyisovalerylcarnitine and the feed conversion ratio (r = −0.430; P = 0.036). Pathway analysis revealed that the most important biological pathway was the phenylalanine, tyrosine, and tryptophan biosynthesis pathway. The results of the research reveal the potential for plasma free amino acid and carnitine profiles to be used as candidate biomarkers in the evaluation of fattening performance in lambs.

Growth Performance of Arsi, Borana, Harar and HF-Crossbred Bulls Finished under Similar Feeding Condition

The study was conducted to evaluate the fattening performance of Arsi, Borana, Harar and Holstein Friesian crossbred bulls finished under a similar feeding condition at the beef farm in Haramaya University. The average daily weight gain of the four breeds ranges from 0.49 to 0.71 kg. Feed conversion efficiency also ranges from 0.11 - 0.15. Simple linear regression models were used to explore the relationship between live body weight change and change in body condition score as well as seven linear body measurements for all age groups. An average change for a unite of body condition score was equivalent to 20.3, 20.61, 22.42 and 27.78 kg for Borana, Arsi, Harar and Holstein Friesian crossbred bulls respectively. Body condition score was significantly influenced by breeds. There was a significant breed by age interaction effect on the initial body condition score of the four breeds. There was a significant and positive strong association between change in body weight and body condition score. There was a significant and strong correlation between change in body weight and change in Total topline, neck length, heart girth, flank circumference and rump length having correlation coefficients ranges from 0.57 to 0.97. A higher net profit of 7380.47 ETB per head was recorded by Borana bulls followed by Harar bulls, Arsi and Holstein Friesian crossbred with net profit of 5406.86, 5193.29 and 3384.98 ETB per head respectively. Borana bulls are more superior in weight gain and net profit. Bodyweight change could be predicted based on body condition score change during the fattening period.

Determination of the Optimum Fattening Period and Fattening Performance Slaughter and Carcass Characteristics of Hair Goat and Saanen × Hair Goat (G1) Crossbred Kids Fattened in Different Systems

This research was carried out to investigate the fattening performance and slaughter and carcass characteristics of Hair goat and Saanen × Hair goat (G1) crossbred kids in different fattening systems. Thirty Hair goats and 30 Saanen × Hair goat (G1) crossbred singleton male kids 2.5-3 months old and weaned were used. The kids were fattened in three different systems: intensive, semi-intensive, and extensive. Marginal value analysis was applied to determine the optimum feeding periods of the kids. In order to determine the slaughter and carcass characteristics, all the kids fattened were taken to slaughter after determining their live weight at the end of the fattening. Live weight gains after the intensive, semi-intensive, and extensive fattening were 17.83 kg, 19.39 kg, and 18.29 kg in the Hair goat kids and 17.88 kg, 18.24 kg, and 17.32 kg in the Saanen × Hair goat (G1) crossbred kids, respectively. In the same order, the average concentrate feed consumed by kids for 1 kg live weight gain was 7.55 kg, 7.28 kg, 7.00 kg and 7.07 kg. Hot carcass weights after the intensive, semi-intensive, and extensive fattening were 13.58, 14.06, and 13.02 kg in the Hair goat kids and 14.21, 15.03, and 14.06 kg in the Saanen × Hair goat (G1) crossbred kids. The Saanen × Hair goat (G1) crossbred goats increased more in live weight than the Hair goat kids and the semi-intensive fattened goats increased more in live weight than the intensive and extensive fed goats. Moreover, the optimum fattening times generally varied between the groups, but not between genotypes within the group.

Effect of Carob Pulp (Ceratonia Siliqua L.) on Fattening Performance, Carcass Characteristics and Meat Quality of Moroccan Breed Deroua Lambs

This study aimed to evaluate the effect of incorporating different levels of carob pulp (CP) on fattening performance, carcass characteristics and meat qualityof the Moroccan sheep breed Deroua. Thirty-six entire maleMoroccan breed Deroua lambs with aninitial body weight of 23.5±3.1 kg and age 120±10 days, were randomly divided into three diet’streatmentsof 12 animals: T0(0%CP), T1(10%CP) and T2(20%CP) containing 0, 10 and 20 % of CP, respectively. The experiment lasted 80 days, including 5 days of adaptation to different diets. Lambs were weighed every 15 days, while feed intake was determineddaily. At the end of the experiment, 27 lambs (9per treatment) were slaughtered to determinecarcass characteristics and meat quality. Final body weight and average daily gain (P&lt;0.05) were affected by treatment diet. The inclusion of 10% CP led to a decrease in feed conversion ratio and feeding costs. Carcass characteristics were not affected by diets (P&gt;0.05),except, in case of mesenteric fat (P&lt;0.05) with superiority recorded in treatment diet T1(10%CP). Meat quality parameters were not affected by diets. The meat of lambs feddiets T1 and T2 tended to be lighter in color and less red than those fed diet T0. The results of this work showed that carob pulp can be used as an alternative feedstuff from fattening lambs to reduce feeding costs without affecting fattening performance.

Effects of oregano essential oil and capsicum extract on fattening, serum constituents, and rumen fermentation of lambs

This study investigated dietary supplementation of weaned lambs with Origanum vulgare essential oil and Capsicum oleoresin (chilli pepper) extract. Thirty-six eight-week-old male and female Menemen lambs were used in this study. Three dietary treatment groups consisted of T1, an unsupplemented control group; T2, a group supplemented with 300 mg/kg oregano essential oil, and T3, a group supplemented with 300 mg/kg Capsicum oleoresin. Feed and fresh water were available to the lambs ad libitum during the 56-day experiment. No significant effects of treatment were detected on growth rate, feed intake and feed conversion. In addition, serum urea, creatine, total protein, albumin, amylase, aspartate amino transferase (AST), alanine amino transferase (ALT), and gamma glutamyl transferase (GGT) levels did not differ among treatments on day 56 of the study. When oregano oil and capsicum extract were added to the feed, total volatile fatty acids (TVFA), acetate (AA), propionate (PA), butyrate (BA), isobutyrate (IBA), valerate (VA), and AA to PA ratio in the rumen were decreased significantly in comparison with the control group at two hours after feeding, with the effect of T2 being greater than that of T3. Female lambs had lower levels of TVFA than male lambs. Thus, although neither additive affected fattening performance and serum constituents of the lambs, both altered the rumen fatty acid profile.