Performance and carcass characteristics in fattening lambs feed diets with different levels of pistachio by-products silage with wasted date

Early feeding strategies in lambs affect rumen development and growth performance, with advantages persisting for two weeks after the transition to fattening diets

This study aimed to explore the effects of early feeding strategies on the growth and rumen development of lambs from pre-weaning to the transition to fattening diets. Ninety-six newborn, male lambs with similar body weights were randomly assigned to three treatments: fed starter at 42 days old + weaned at 56 days old (Ctrl, n = 36), fed starter at 7 days old + weaned at 56 days old (ES, n = 36), and fed starter at 7 days old + weaned at 28 days old (ES + EW, n = 24). The fattening diets of all lambs were gradually replaced from 60 to 70 days of age. Six randomly selected lambs from each treatment were slaughtered at 14, 28, 42, 56, 70, and 84 days of age. The results showed that the richness and diversity of rumen microbiota of lambs in the Ctrl group were distinct from those of lambs in the other groups at 42 days of age. Moreover, transcriptome analysis revealed 407, 219, and 1,211 unique differentially expressed genes (DEGs) in the rumen tissue of ES vs. Ctrl, ES vs. ES + EW, and ES + EW vs. Ctrl groups, respectively, at 42 days of age. Different early feeding strategies resulted in differences in ruminal anatomy, morphology, and fermentation in lambs from 42 to 84 days of age (P < 0.05). Lambs in the ES + EW group had a higher average starter diet intake than those in the other groups (P < 0.05) from 28 to 56 days of age, which affected their growth performance. After 42 days of age, the body and carcass weights of lambs in the ES and ES + EW groups were higher than those in the Ctrl group (P < 0.05). These findings demonstrate that feeding lambs with a starter diet at 7 days of age and weaning them at 28 days of age can promote rumen development and improve growth performance, and this advantage persists for up to 2 weeks after transition to the fattening diet.

Fennel (Foeniculum vulgare) seed powder increases Delta-Like Non-Canonical Notch Ligand 1 gene expression in testis, liver, and humeral muscle tissues of growing lambs

Delta-Like Non-Canonical Notch Ligand 1 (DLK1) is one of the key genes involved in the development of muscle, liver, pancreas, and lung cells; adipocytes production; and the improvement of digestion, growth performance, and meat quality. It has been documented that fennel is effective on increasing the DLK1 gene (DLK1) expression in the testis, liver, and muscle tissues, which may consequently have important implications for sheep production. Hence, the aim of the current investigation was to evaluate the fennel seed powder's effect on DLK1 expression in testis, liver, and humeral muscle tissues in growing lambs. For the purpose of this study, 30 male Kermani sheep were fed with three different group of diets (number of animals in each group was 10), including control (without any fennel seed powder), treatment 1 (with 10 g/kg of dry matter (DM) fennel seed powder), and treatment 2 (with 20 g/kg of DM fennel seed powder) during a 3-month period. Thereafter, total RNA was extracted, cDNA was synthesized, and Real-Time PCR was performed. The addition of fennel seed powder (in the treatment 1 and treatment 2 groups) in the growing lambs diets consequently resulted in greater expression of DLK1 in both the liver and humeral muscle tissues compared to the testis tissue (P < 0.05). Furthermore, the increased DLK1 expression was higher in the tissue of humeral muscle (P < 0.05) in comparison to the other two tissues. As well, the concentration of blood testosterone was greater (P < 0.05) for the animals fed with fennel powder compared to growing lambs fed with the control diet. However, the concentrations of blood liver enzymes, including serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT), decreased by the addition of 10 g/kg DM fennel to diets of lambs compared to the control diet (no fennel). Therefore, it can be concluded that using fennel seed powder in the diet of growing lamb by affecting the expression of DLK1, can improve the concentrations of blood testosterone, SGOT, SGPT, and muscle structure (increased mass of muscle and size of muscle fiber).

Growth Performance, Meat Quality and Antioxidant Status of Sheep Supplemented with Tannins: A Meta-Analysis

The objective of this study was to evaluate the effects of dietary supplementation with tannins (TANs) on productive performance, carcass characteristics, meat quality, oxidative stability, and blood serum antioxidant capacity of sheep through a meta-analysis. Using Scopus, Web of Science, ScienceDirect, and PubMed databases, a systematic search was performed for studies published in scientific journals that investigated the effects of TANs supplementation on the variables of interest. Only studies with weaned or older sheep were included. The data analyzed were extracted from 53 peer-reviewed publications. The sheep included in the present study were between 2 and 6 months old, and between 12 and 31 kg of body weight. The effects of TANs were analyzed using random-effects statistical models to examine the standardized mean difference (SMD) between treatments with TANs and control (no TANs). Heterogeneity was explored by meta-regression and a subgroup analysis was performed for covariates that were significant. Supplementation with TANs did not affect dry matter intake, pH, color (L* and b*), Warner-Bratzler shear force, cooking loss and meat chemical composition (p > 0.05). Supplementation with TANs increased daily weight gain (SMD = 0.274, p < 0.05), total antioxidant capacity (SMD = 1.120, p < 0.001), glutathione peroxidase enzyme activity (SMD = 0.801, p < 0.001) and catalase (SMD = 0.848, p < 0.001), and decreased malondialdehyde (MDA) concentration in blood serum (SMD = -0.535, p < 0.05). Supplementation with TANs decreased feed conversion rate (SMD = -0.246, p < 0.05), and the concentration of MDA (SMD = -2.020, p < 0.001) and metmyoglobin (SMD = -0.482, p < 0.05) in meat. However, meat redness (SMD = 0.365), hot carcass yield (SMD = 0.234), cold carcass yield (SMD = 0.510), backfat thickness (SMD = 0.565) and the Longissimus dorsi muscle area (SMD = 0.413) increased in response to TANs supplementation (p < 0.05). In conclusion, the addition of tannins in sheep diets improves productive performance, antioxidant status in blood serum, oxidative stability of meat and some other characteristics related to meat and carcass quality.

The effect of using diet supplementation based on argane (Argania spinosa) on fattening performance, carcass characteristics and fatty acid composition of lambs

The current study was performed in order to evaluate the effect of using argane by-products (oil cake and pulp) as fattening diet of lambs. This was achieved through an experimental lamb fattening investigation using argan by-product as feeding source and the exploration of the fattened lamb performance, carcass characteristics and the chemical fatty acid composition of the quality produced meat. Twenty fattening Sardi lambs (26 ± 0.5 kg body weight and six months old) were divided into two (n = 10) homogenous experimental and control groups. Argane by-products (ABP) and traditional (CF) diets have been used for feeding the experimental and control groups respectively during a period of 75 days. The results obtained for both groups were used to determine the effect of feeding argane by-products on animal weight, average daily gain (ADG), carcass weight, muscle pH values, dressing %, dry matter, ash, ether extract, crude fiber, crude protein, and fatty acid composition. The obtained results showed that the experimental ABP group lambs had higher average daily gain and meat chemical, crude protein and ash and proportion of C18:0 than the control CF group lambs, while the control CF group had a higher feed conversion ratio, ether extract, mesenteric and perirenal fat. The results obtained for pH0 and pH24 were similar for both explored groups. The obtained results showed thus that the use of ABP as a diet to fattening lambs increased their performance and lean meat yield.

Growth performance and carcass characteristics of finishing male lambs fed barberry pomace-containing diets

Barberry (Berberis vulgaris) fruits contain bioactive compounds with antimicrobial, antioxidant and hepatoprotective effects. The inclusion of barberry pomace (BP) in finishing diets could potentially enhance growth performance and carcass characteristics of sheep. To test this hypothesis, 21 male Balouchi lambs (24.5 ± 4 kg initial live weight; 5 ± 0.6 months of age) were randomly assigned to three BP-containing experimental diets to determine their effects on feed intake, live weight gain and carcass characteristics. The experimental diets were formulated to meet nutrient requirements for a targeted daily weight gain of 200 g as follows: (1) control diet (BP0), (2) control diet in which 7.5% of alfalfa hay and wheat straw were replaced with BP (BP75), (3) control diet in which 15% of alfalfa hay and wheat straw were replaced with BP (BP150). Lambs were fed the experimental diets for 75 days during which feed intake and live weight changes were recorded. At the end of the feeding period, lambs were fasted for 16 h, weighed and then slaughtered in order to determine carcass characteristics. Experimental diets had no effect on feed intake and growth performance of lambs. Similarly, diets had no effect (p > 0.05) on weight of carcass, commercial cuts (neck, shoulder, loin, leg, fat-tail, brisket, flank) and non-carcass components (head, skin, feet, lung and trachea, heart, liver, spleen, gastro-intestinal, kidney, bladder and testicles) but linearly increased (p < 0.05) warm and cold dressing percentage as well as heart weight. These results do not support the hypothesis that feeding BP-containing diets enhances growth performance and carcass characteristics of male Balouchi lambs. However, inclusion of BP had no negative effects on animal performance and carcass characteristics.

Effects of pearl millet silage ammoniation with urea on carcass and meat quality of lambs

This study aimed to evaluate the effect of pearl millet silage ammoniated with urea on lamb carcass characteristics and meat quality. Thirty-two noncastrated crossbred lambs at 4-5 months of age, with an average initial body weight of 17.39 ± 2.16 kg, were distributed into four treatments in a randomized block experimental design with eight animals per treatment. Experimental diets were composed of pearl millet silage ammoniated with four levels of urea (0%, 2%, 4% and 6%, on dry matter basis (DM). Carcass conformation and fatness decreased linearly (p < 0.05). Except for the fat content, the proximate composition was not influenced (p < 0.05) by the diets. Meat lightness and yellowness increased linearly (p < 0.05). There was no effect of diets (p > 0.05) on cooking losses or shear force. The levels of oleic and erucic fatty acid levels in the meat decreased linearly (p < 0.05), whereas linoleic and eicosadienoic acids, polyunsaturated fatty acids, PUFA:SFA ratio and ω6 contents increased (p < 0.05). Pearl millet silage ammoniated with urea allows for the production of good-quality lamb meat, with greater concentrations of polyunsaturated fatty acids. However, lambs fed diets with pearl millet ammoniated with up to 6% lead to a reduction of carcass characteristics without significantly affecting loin-eye area possibly associated with low palatability of the additive used. The lower acceptance of the silages with higher levels of urea is due to the ammonia retention in the material is attributed to the ammonization process. Thus, in spite of the benefits on lamb meat quality, it is suggested that the use of this additive in the ammonization of tropical forages be carried out with care, in limits of up to 6%.