Pasture Height of A Tropical Erect Grass Affecting Young Lamb Herbage Intake And Performance

Tropical erect grass pastures have high forage production potential in subtropical and tropical regions of the world. However, in this kind of pasture, the body weight gain of weaned lambs is usually below of their potential. We determined the effect of pasture height of an erect tropical grass, consequently its structure, on intake and performance of young lambs. The experiment was repeated in two years. Thirty young weaned lambs (4-5 months) were assigned, each year, to three Panicum maximum pasture heights: 1) Tall-75 cm; 2) Medium-50 cm and 3) Short-25 cm. Herbage mass, pasture height, plant morphological composition, pasture nutritional quality, lamb’s average daily gain, gain per hectare and herbage intake were measured. The experiment was installed in a completely randomized design, evaluated in two periods each year. The Short treatment presented, on average and for longer, the highest leaf:stem ratio (1.3 ± 0.23) and average daily gain (91 ± 10 g/day) in relation to the Medium and Tall treatments (68 ± 10 and 40 ± 13 g, respectively). There was a significant interaction between treatment*period for herbage intake. The Tall treatment showed a marked decrease in intake from the first to the second period. The pasture height management interferes in the speed at which the number of stems increases of a tropical erect grass, in relation to leaves. For a better performance of weaned young lambs during summer-autumn period, it is important to manage tropical erect grass pastures at lower height than is generally recommended, lower than 25 cm.

Impact of mother genetic and resource environment on her offspring’s growth features in Munjal sheep

Summary The present study evaluated maternal and additive influences that contribute to phenotypic variation in various growth traits in Munjal sheep. The targeted traits that pertained to 2278 records of 706 lambs were birth weight (BWT), weaning weight (WT3), 6-month body weight (WT6), 12-month body weight (WT12), average daily gain (ADG1: 0–3 months; ADG2: 3–6 months, ADG3: 6–12 months of age) and their corresponding Kleiber ratios designated as KR1, KR2 and KR3. The direct heritability estimates for BWT, WT3, WT6, WT12, ADG1, ADG2, ADG3, KR1, KR2 and KR3 under animal models were 0.20 ± 0.08, 0.28 ± 0.08, 0.17 ± 0.07, 0.47 ± 0.09, 0.33 ± 0.08, 0.09 ± 0.06, 0.36 ± 0.10, 0.33 ± 0.08, 0.09 ± 0.06 and 0.32 ± 0.10, respectively. The estimates of maternal genetic effects contributed significantly and were 8% and 7% for BWT and WT3 traits, respectively, which highlighted the considerable role of maternal effects on early growth traits. Genetic and phenotypic correlations ranged from moderate to high between weaning and post-weaning traits. It was concluded that early selection that considered additive as well as maternal effects at weaning age may be delivered to the desired genetic progress in Munjal sheep.

l-Isoleucine Administration Alleviates DSS-Induced Colitis by Regulating TLR4/MyD88/NF-κB Pathway in Rats

Inflammatory bowel disease (namely, colitis) severely impairs human health. Isoleucine is reported to regulate immune function (such as the production of immunoreactive substances). The aim of this study was to investigate whether l-isoleucine administration might alleviate dextran sulfate sodium (DSS)-induced colitis in rats. In the in vitro trial, IEC-18 cells were treated by 4 mmol/L l-isoleucine for 12 h, which relieved the decrease of cell viability that was induced by TNF-α (10 ng/ml) challenge for 24 h (P <0.05). Then, in the in vivo experiment, a total of 44 Wistar rats were allotted into 2 groups that were fed l-isoleucine-supplemented diet and control diet for 35 d. From 15 to 35 d, half of the rats in the 2 groups drank the 4% DSS-adding water. Average daily gain, average daily feed intake and feed conversion of rats were impaired by DSS challenge (P <0.05). Drinking the DSS-supplementing water also increased disease activity index (DAI) and serum urea nitrogen level (P <0.05), shortened colonic length (P <0.05), impaired colonic enterocyte apoptosis, cell cycle, and the ZO-1 mRNA expression (P <0.05), increased the ratio of CD11c-, CD64-, and CD169-positive cells in colon (P <0.05), and induced extensive ulcer, infiltration of inflammatory cells, and collagenous fiber hyperplasia in colon. However, dietary l-isoleucine supplementation attenuated the negative effect of DSS challenge on growth performance (P <0.05), DAI (P <0.05), colonic length and enterocyte apoptosis (P <0.05), and dysfunction of colonic histology, and downregulated the ratio of CD11c-, CD64-, and CD169-positive cells, pro-inflammation cytokines and the mRNA expression of TLR4, MyD88, and NF-κB in the colon of rats (P <0.05). These results suggest that supplementing l-isoleucine in diet improved the DSS-induced growth stunting and colonic damage in rats, which could be associated with the downregulation of inflammation via regulating TLR4/MyD88/NF-κB pathway in colon.

META-ANALYSIS OF PHYTOGENIC ADDITIVES FOR BROILERS

Phytogenic additives have been studied intensively in broiler chickens’ production to substitute growth-promoting antibiotics. However, the comprehensive literature on this topic makes it difficult to understand overall results because there are a noticeable number of studies with conflicting conclusions. While several research studies have shown that phytogenic additives may increment broiler chicken’s performance, others make the opposite evident. This study aimed to organize and understand information through meta-analysis considering a great number of publications and the factors that may interfere in the results of phytogenic additives, evaluating whether phytogenic additives can be used as a performance-enhancing additive for broilers, comparing with the effectiveness of growth-promoting antibiotics. The main factor that interferes in the evaluation of phytogenic additives is the microbiological challenge. Phytogenic additives improved average daily gain (ADG) (P < 0.001) and feed conversion (P < 0.001) regardless of microbiological challenge; however, they were worse compared to antibiotics under higher challenge (P < 0.020). A meta-regression of ADG in function of average daily feed intake confirmed that phytogenic additives increased the feed efficiency of broilers, but with less effectiveness than antibiotics. The blends of phytogenic additives increased the ADG in relation to the isolated use of only one phytogenic additive.

Effects of salinity and plant-based diet or animal-plant combination diet on the performance and metabolic status of juvenile Nile tilapia

The purpose of this study was to evaluate the effects of salinity and plant-based diet or animal-plant combination diet on the performance and metabolic status of juvenile Nile tilapia (Oreochromis niloticus). The experimental design was completely randomized in a 4 × 2 factorial scheme with four replicates. The treatments were established by the combination of salinities of 0, 10, 20, and 30 g L-1 with an animal-plant combination diet (AP) or plant-based diet (P). The replicates were 60 L tanks with 12 fish per tank. Diets were provided for 32 days, and the fish were fed three times a day (8, 12, and 17 h) until apparent satiety. Daily feed intake (DFI) was measured, body weight (BW) was recorded at the beginning and end of the trial, and total length (TL) and standard length (SL) were measured at the end of the trial. Average daily gain (ADG), specific growth rate (SGR), feed conversion ratio (FCR), and survival rate were calculated. After the biometric measurements were made at the end of the trial, blood samples were collected to determine the plasma concentrations of total protein (TP), glucose, cholesterol, and triglycerides (TG). The fish were euthanized, and the hepatopancreas was collected and weighed; thereafter, the hepatosomatic index (HSI) was calculated. An interaction was detected between salinity and diet type for final BW, ADG, TL, and SL. These traits were not influenced by salinity when it was associated with the AP diet, but reduced linearly with salinity in the P diet. DFI and survival rate were independently affected by salinity: DFI reduced linearly with salinity levels and survival rate was higher at a salinity of 10 g L-1. HSI increased linearly with salinity levels and was lower in the P diet than in the AP diet. Salinity had a quadratic effect on plasma TP, and the maximum value for this metabolite (2.96 g dL-1) is attained at a salinity of 10.26 g L-1. There was an independent effect of diet on the plasma concentrations of cholesterol and TG, which were lower in the P diet than in the AP diet. The salinity of 10 g L-1 associated with diet composed of animal and plant ingredients led to a better performance, higher survival rate, and less stressful environmental conditions for juvenile Nile tilapia.

Lambs Fed Diets Containing By-Product from Coconut Processing: Histomorphometry Characteristics in the Digestive and Renal Systems

This study aimed to evaluate the histological characteristics in the digestive and renal systems of lambs fed diets containing coconut by-product (CB). A total of 35 male lambs with an initial weight of 16.9 ± 2.93 kg were distributed in a completely randomized design with five levels of CB in the diet (0; 4.8; 9.6; 14.4 and 19.2% in total dry matter). Samples of the liver, kidney, rumen, and intestine were histomorphometrically evaluated and the data were submitted to regression analysis, at a 5% error probability. The inclusion of CB linearly decreased the dry matter intake and caused a quadratic effect for the height of ruminal papillae, absorption area, epithelium thickness, as well as for average daily gain. The inclusion of CB linearly increased the mucous layer and reduced the submucosal layer, as well as promoted a decrease in goblet cells in the small intestine. The inclusion of BC did not influence hepatic glycogen, additionally, the histopathological examination did not reveal liver damage or congestion, vacuolization, and necrosis of the renal tissue. Therefore, our results indicate that CB can be included in lambs diet up to the level of 7.2% without causing changes in the histomorphometry characteristics of the gastrointestinal tract and changes in liver and kidney tissue that compromise animal performance.

Effect of Dietary Vitamin E on Growth Performance, Immunity and Antioxidant Capacity in Male Jiangnan White Goslings from 1 to 28 d of Age

This experiment aimed to investigate effects of the different dietary levels of vitamin E (VE) on the growth performance, immunity and antioxidant capacity of goslings. A total of 240 1-day-old, male Jiangnan white goslings were selected and randomly divided into 6 groups. Each treatment included five replicates. The basal diet was supplemented with 6 concentrations of VE (0, 12, 24, 36, 48 and 60 mg DL-α-tocopherol acetate/kg). The results were as follows: (1) The α-tocopherol content in the serum and liver of goslings increased linearly as supplemental VE increased in diet (p < 0.05). (2) The body weight (BW) and average daily gain (ADG) increased quadratically with increasing dietary VE supplementation (p < 0.05). Dietary VE supplementation could significantly reduce the feed/gain ratio (F/G) (p < 0.05). (3) Dietary supplementation with VE could significantly improve the contents of immunoglobulin A (IgA) and immunoglobulin G (IgG) in the serum of the goslings (p < 0.05). The content of interferon-γ (IFN-γ) in the serum was significantly reduced with VE supplementation (p < 0.05). (4) Dietary supplementation with VE could significantly improve serum and liver catalase (CAT), superoxide dismutase (SOD) activities and liver total antioxidant capacity (T-AOC) (p < 0.05); Serum and liver MDA contents were significantly reduced with VE supplementation (p < 0.05). In summary, dietary supplementation with VE could improve growth performance, immunity and antioxidant capacity. Based on broken-line regression analysis, the dietary VE supplementation level for ADG was 12.51 mg/kg, but higher supplementation level should be considered to improve immunity and antioxidant capacity.

Protein-energy supplementation on productive and nutritional performance of grazing beef heifers

This study was conducted with the aim of evaluating the effect of protein-energy supplementation on productive performance, intake, digestibility, and microbial protein synthesis in heifers fed tropical forage. Twelve Nellore heifers at 11 months of age, with a mean initial body weight of 248.8 ± 11.40 kg were used. The animals were distributed in a completely randomized design with two treatments and six replicates. The treatments evaluated were: control (without supplementation); and supplementation in the amount of 1.5 kg animal-1 day-1. Forage samples were collected to evaluate the chemical composition and the total availability of dry matter of the pasture consumed by the animals. To evaluate the intake and forage digestibility, a trial was performed using internal and external markers. In this study no effect of supplementation was observed on the intakes of dry matter (DM), organic matter (OM), forage DM, or neutral detergent fiber corrected for ash and protein (NDFap; P > 0.10). However, supplementation increased (P < 0.01) the intakes of crude protein (CP), ether extract (EE), and non-fibrous carbohydrates (NFC). Additionally, an upward trend (P=0.076) was observed in the intake of digested OM (DOM) with supplementation. On the other hand, supplementation increased (P < 0.01) the digestibility coefficients of OM, CP, EE, and NFC, although supplementation did not affect the ruminal synthesis of nitrogen compounds (MICN), efficiency of protein microbial synthesis (EMS), relative microbial nitrogen (RMICN) or urine urea nitrogen (UUN) excretion (P > 0.57). Lastly, supplementation increased (P=0.050) the average daily gain of the animals, although no effect (P > 0.10) was observed on their final body weight. These results suggested that protein-energy supplementation improves the productive performance and nutritional characteristics of grazing beef heifers.

The Performance and Carcass Characteristics of Black Baladi Kids Fed Diets with Graded Quantities of Sweet Lupin Grain (Lupinus angustifolius)

A study was conducted to examine how lupin grains (LUPs) feeding affected nutritional intake, digestibility, growth, and carcass characteristics in kids. A total of 24 growing black kids (initial body weight (BW) = 16.4 ± 0.49 kg) were allocated to one of three diets at random. Lupin was included in the diet at a rate of 0 (control; CON), 100 (LUP100), or 200 g/kg (LUP200) of total dry matter (DM). The trial lasted for 91 days divided into 7 and 84 days to be used for adaptation and data collection, respectively. Feed intake was evaluated daily throughout the study. At the commencement and the end of the study, each kid’s body weight was measured to determine its average daily gain (ADG). On day 70, 5 kids were chosen at random from each group to investigate nutrient in vivo digestibility and N balance. At the end of the study, all of the kids were slaughtered to examine carcass features. Nutrient intakes (neutral detergent fiber, acid detergent fiber, and ether extract) were higher (p ≤ 0.01) in LUP-containing diets than in the CON diet. The average daily gain was greater (p ≤ 0.03) in diets containing lupin grains than in the CON diet. Cost of gain ($US/kg growth) was lower (p = 0.004) in kids fed diets containing lupin than the CON diet. Dry matter and CP digestibility rates were greater (p ≤ 0.03) in lupin diets. Retained N was higher (p = 0.04) in lupin-containing diets than in the CON diet. Cold carcass weight was higher (p < 0.05) for kids consuming the LUP100 diet than the CON diet. In lupin diets, carcass cut weights were higher (p < 0.05). Results of the current study indicate that feeding black kids diets containing lupin grains at 100 or 200 g/kg DM basis is cost effective and would increase profitability.

STRESS-RESISTANT OF PUREBRED AND CROSSBRED PIGS OF DIFFERENT BRED COMBINATIONS

The authors presented the results of experimental studies on the stress-resistant of pigs. The first group is a breed created in Sapphire Ltd. This breed is a breeding group (BG) in purebred breeding and their mixtures in two- and three-breed combinations with Landrace (L) and Duroc (D) boars under conditions of industrial farm technology in Siberia. Two methods assessed stress-resistant of piglets of different breed groups. The first method is “weaning crisis”. The second method is a com-parison of cortisol levels in the blood. Three-breed weanling piglets (SGxL)xD turned out to be the most stress-sensitive. Stress-resistant piglets had an effect on their growth during the rearing period. During this period, stress-resistant animals of all breed combinations had higher average daily gain than stress-sensitive animals (P < 0.001). Stress-resistant animals of the breeding group (SG) showed an average daily growth of 547.5 g during the fattening period. Also, the stress-resistant animals of the breeding group reliably surpassed the stress-sensitive pigs by 461.4 g (P < 0.01), the two-breed pigs by 455.9 g and 404.7 g and the three-breed pigs 451.8 g and 419.2 g, respectively. There was a statistically significant advantage in the indices of the average daily gain among the purebred young-sters of the breeding group (SG) (543 g) compared to the two-breed pigs (447g) and the three-breed pigs (402g), i. e., by 17.8 % and 26 % at P < 0.001. The authors found that the EAAcr/- genotype in stress-sensitive pigs was more common than EAA-/(0.71 ± 0.07 vs 0.48 ± 0.09). Stress-resistant pigs of the breeding group (SG) with EAE edg/edf blood group genotypes were characterized by increased growth intensity and reliable superiority over stress-sensitive pigs. The authors believe that these genotypes can be accepted as preliminary candidates for genetic markers of stress resistant. Blood cortisol levels appeared to be unrelated to stress-resistant compared to the “weaning crisis” method. This relationship (blood cortisol level with stress-resistant) applies to all studied breed combinations, both individually and as a whole.