How can housing system affect growth and carcass traits, meat quality and muscle fiber characteristics in biceps femoris and mineral content of tibia and femur bones in growing rabbits?

Improving quality and consumer acceptance of rabbit meat: Prospects and challenges

Rabbit meat is an excellent source of high-quality proteins, essential fatty acids, vitamins, and minerals, which can be further improved through various management, preslaughter, and post-slaughter interventions. Rabbit meat consumption is popular in certain regions of the world. The multidimensional role of rabbits as pet, pest, and laboratory animals, lack of proper knowledge among consumers towards the nutritive value of rabbit meat, animal welfare, and ethical issues, sustainable potential, undeveloped marketing, and processing chain, and price parity with available cheap meat and non-meat alternatives, are some constraints in the rabbit meat production. Increasing awareness of the nutritive value, positive health effects of rabbit meat consumption and production chain, development of processed meat products, and proper animal welfare compliance in rabbit production could improve consumer acceptance. The present manuscript reviewed various factors that affect the meat quality and consumer acceptance of rabbit meat for a more sustainable and viable source for global meat supply.

Tibia properties in broilers raised on their own commercial diets with different growth rates and sex during a 10-week rearing period

BACKGROUND

Genetic selection applied to broilers results in fast growth and an increase in meat yield. However, this situation causes welfare problems in broilers.

OBJECTIVES

The aim of this study is to determine the weekly changes in the tibia characteristics in broilers raised on their own commercial diets.

METHODS

In the study, 168 (84 female and 84 male) slow-growing (Hubbard-Isa Red JA) and 168 (84 female and 84 male) fast-growing (Ross-308) day-old broiler chicks were used. Six broilers from each genotype and sex group were weighed weekly and slaughtered to determine the tibia properties during the 10-week fattening period.

RESULTS

Fast-growing broilers had higher tibia weight and longer length, diaphysis diameter and medullary canal diameter than those of slow-growing broilers at the same age. In fast-growing genotypes, the cortical index was low only in the 2nd week, and Robusticity and Seedor indices were observed to be better throughout the whole fattening. The ash content of the total tibia in the fast-growing broilers was higher in all of the examined weeks except the 4th week and the 9th week of fattening than that in the slow-growing broilers. Although the amount of ash per unit body weight in the 1st week of fattening was higher in fast-growing broilers, this situation reversed after the 4th week. The level of all minerals examined in total tibia weight is high in fast-growing broilers, and they differed according to the fattening period.

CONCLUSIONS

When comparing tibia characteristics of two different genotypes fed their own commercial diets, the tibia structure was found to be stronger in fast-growing broilers compared to other genotypes at the same age, but slow-growing broilers were more prominent in terms of body weight. It was observed that the mineral density was higher in male broilers, except in the 1st week.

The Effect of Carbamazepine on Performance, Carcass Value, Hematological and Biochemical Blood Parameters, and Detection of Carbamazepine and Its Metabolites in Tissues, Internal Organs, and Body Fluids in Growing Rabbits

Antiepileptic drugs (e.g., carbamazepine; CBZ) are widely prescribed for various conditions beyond epilepsy, including neurologic and psychiatric disorders. These medications can have both favorable and unfavorable impacts on mood, anxiety, depression, and psychosis. CBZ has been found at low concentrations (in the unit of nanograms per liter) in rivers, surface water, and even drinking water. As a result, when reclaimed wastewater is used for irrigation in agricultural ecosystems, CBZ can be reintroduced into the environment. That is why we tested different doses of CBZ in rabbits' feed as the meat is consumed in every community, has no religious barriers, and the potential risk of consuming meat which has been exposed to CBZ treatment is not known. Also, the evidence of the effect of CBZ on rabbits is missing. Mainly, the CBZ doses affected the count of leukocytes and other blood traits, meaning the higher the dose, the higher the reduction. Moreover, there were only low amounts of CBZ in rabbits' meat or tissues when they were exposed to the treatment.

The effect of housing system on rabbit growth performance, carcass traits, and meat quality characteristics of different muscles

The present study analysed the effect of housing system (caged versus penned) on the growth performance, carcass traits, and meat quality of rabbits. The physiochemical quality of five muscles was evaluated, together with the chemical composition and fatty acid profile of the meat from the hind leg. Sensory properties of the longissimus lumborum (LL) was also assessed. The LL yields were higher in caged rabbits. According to the results, meat from rabbits raised in cages had higher b* values for the LL (i.e., meat was yellower) than rabbits raised in pens. In addition, the quadriceps femoris from penned rabbits had higher a* and b* values (i.e., were redder and yellower) than caged rabbits. The MUFAs (18:1 n-9 and 20:1 n-9) and ash contents of the hind leg meat were higher in caged rabbits. In conclusion, while housing system influenced the physiochemical traits of rabbit meat, the sensory properties were not influenced.

Laying hens under smallholder conditions: laying performance, growth and bone quality of tibia and femur including essential elements

The study aimed to assess laying performance, growth rate, and bone quality properties of tibia and femur bones of various genotypes of laying hens, including determining essential element composition at the end of the laying cycle in smallholder conditions. The study included three genotypes of laying hens; Czech golden spotted (CGS), White Leghorn (LE) and Dominant Partridge D300 (D300) hens. In total, 180 hens (60/genotype) were used in 3 replications (20 hens/replication). The eggs were collected to determine egg lay and hen-day egg production. Additionally, feed consumption was recorded to determine feed consumption per day or egg, resp. The mortality rate was recorded. Hens were individually weighed every 10 wk to analyze the growth performance and body weight changes during the laying cycle. The differences in performance characteristics were observed as significant in all studied parameters. The bone quality analysis consisted of the determination of bone weight, length, width, and fracture toughness. Furthermore, dry matter, ash, and selected elements, which included boron (B), calcium (Ca), cadmium (Cd), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), sodium (Na), phosphorus (P), lead (Pb), and zinc (Zn) were assessed. Regarding the results of tibia and femur bones, the effect of genotype was determined as significant in all evaluated properties. In terms of element composition, all evaluated elements significantly differed among the genotypes in the tibia (with one exception of Cu) and in the femur (with one exception of Cd). In conclusion, our results showed that hens’ performance, production quality, mortality and bone properties significantly differed among genotypes under smallholder conditions. Thus, every genotype needs to be carefully considered, when the rearing conditions are set.

The Effect of Housing System and Gender on Relative Brain Weight, Body Temperature, Hematological Traits, and Bone Quality in Muscovy Ducks

The study was conducted during the summer season (June–August 2020). Two hundred sixty-four 5-week-old sexed Muscovy ducklings were randomly divided into four equal experimental groups by housing system and by gender. Each group had three replicates (22 birds/replicate) in a randomized design experiment. Regarding the hematological traits, the volume of leukocytes was higher in the D group (by 0.34 × 109/L; p < 0.05) than in the S group. Furthermore, body temperature was found to be higher in ducks (by 0.84 °C; p < 0.05) and in the D group (by 0.5 °C; p < 0.05) in comparison with drakes and birds from the S group. Considering relative brain weight, drakes had higher values than ducks (by 0.56 g; p < 0.05), and birds from the S group also manifested higher values (by 0.78 g; p < 0.05). In terms of bone quality, there were no differences in studied parameters of tibia and femur bones regarding housing systems. The results provide valuable evidence of differences in the fattening of intensively bred Muscovy ducks within the housing system but also regarding gender.