Impact of Citrus Pulp or Inulin on Intestinal Microbiota and Metabolites, Barrier, and Immune Function of Weaned Piglets

We investigated the use of citrus pulp (CP) as a novel prebiotic capable of exerting microbiota and immunomodulating capacities to alleviate weaning stress. Inulin (IN), a well-known prebiotic, was used for comparison. Hundred and 28 male weaned piglets of 21 days old were assigned to 32 pens of 4 piglets each. Piglets were assigned to one of the four treatments, i.e., control, IN supplemented at 0.2% (IN0.2%), and CP supplemented either at 0.2% (CP0.2%) or at 2% (CP2%). On d10–11 and d31–32 post-weaning, one pig per pen was euthanized for intestinal sampling to evaluate the growth performance, chyme characteristics, small intestinal morphology, colonic inflammatory response and barrier integrity, metabolite profiles [gas chromatography-mass spectrometry (GC-MS), and liquid chromatography-mass spectrometry (LC-MS)], and microbial populations. The IN treatment and the two CP treatments induced higher small intestinal villus height to crypt depth ratios in comparison with the control diet at both sampling times. All treatments decreased acidic goblet cell absolute counts in the crypts in comparison to the control diet of the duodenum on d10–11 and d31–32. The gene expression of β-defensin 2 was downregulated in colonic tissues following the IN and CP2% inclusion on d31–32. On d31–32, piglets fed with IN and CP0.2% showed lower mRNA levels of occludin and claudin-3, respectively. Not surprisingly, flavonoids were observed in the colon in the CP treatments. Increased colonic acetate proportions on d10–11, at the expense of branched-chain fatty acid (BCFA) levels, were observed following the CP2% supplementation compared to the control diet, inferring a reduction of proteolytic fermentation in the hindgut. The beneficial microbial community Faecalibacterium spp. was promoted in the colon of piglets fed with CP2% on d10–11 (p = 0.04; false discovery rate (FDR) non-significant) and on d31–32 (p = 0.03; FDR non-significant) in comparison with the control diet. Additionally, on d31–32, CP2% increased the relative abundance of Megasphaera spp. compared to control values (p = 0.03; FDR non-significant). In conclusion, CP2% promoted the growth of beneficial bacterial communities in both post-weaning time points, modulating colonic fermentation patterns in the colon. The effects of CP supplementation were similar to those of IN and showed the potential as a beneficial feed supplement to alleviate weaning stress.

Effects of different energy source diets, as corn substitutes, on carcass characteristics and meat quality of feedlot lambs

This study evaluated the effects of different energy sources, as corn substitutes, on the carcass characteristics and meat quality of lambs. Twenty-four intact ram lambs were identified, weighed, and assigned to one of four dietary treatments: corn, citrus pulp, rice bran, and soybean hulls. The ram lambs were confined in feedlots, and when they reached 30 kg of live weight, they were slaughtered. A completelyrandomized design with different replicates was used for the analysis, along with the Tukey-5% test. For hot and cold carcass weight, rice bran produced lower values than the other dietary treatments. For the red color content of the meat, citrus pulp presented superior values when compared to corn, whereas meat and fat color, loin eye area, and objective tenderness did not differ between treatments. Different energetic sources used to replace corn in ram lambs finishing diets did not affect the proximate composition and quality of the meat. Highlights: • Addition of rice bran to the lambs' diet resulted in lower hot and cold carcass weight.• Animals fed soybean hulls presented the highest carcass compactness index values.• Rice bran extended the feedlot period of lambs in 59.33 days, been longer than the others energies sources.• Corn, rice bran, citrus pulp and soybean hulls did not change the quality of meat but the inclusion of rice bran should be carefully evaluated.

Effect of Fresh Citrus Pulp Supplementation on Animal Performance and Meat Quality of Feedlot Steers

The use of fruit by-products such as citrus pulp represents a feeding ingredient that deserves to be evaluated as an energy source in animal rations. Thirty-six British breed steers were allotted to one of the three feeding treatments (12 steers/treatment): 0%, 15% and 30% of fresh citrus pulp inclusion in the ration in a randomized complete block design to evaluate animal performance and carcass and meat quality traits. In the present study, the inclusion of fresh citrus pulp up to 30% of the diet did not affect the animal average daily gain (p > 0.05) but steers that were fed the pulp consumed less feed (p < 0.05) and presented a lower feed conversion ratio (p < 0.05) than their counterparts without citrus pulp in their diet. No effect of fresh citrus pulp was observed on carcass and meat quality (p > 0.05). A greater lipophilic antioxidant capacity (p < 0.05) in meat was observed when fresh citrus pulp was offered at 15% of the diet. Fresh citrus pulp used up to 30% as a feed ingredient in feedlot rations does not negatively affect animal performance or meat quality but, rather, has a positive effect on dry matter intake and a better feed conversion ratio.

Effect of Feed Supplementation with Clostridium butyricum, Alone or in Combination with Carob Meal or Citrus Pulp, on Digestive and Metabolic Status of Piglets

This work studied the effects of the inclusion of Clostridium butyricum on feed, alone or with carob meal or citrus pulp, on the digestive and metabolic status of weaned piglets. A total of 30 male piglets (weaned at 21 days) is used. There are five dietary treatments: negative without ZnO at high doses (C-), a positive control supplemented with ZnO at 2500 ppm of Zn (C+), supplemented with Clostridium butyricum as a probiotic (PRO), and supplemented with probiotic and 5% carob meal (PROC) or 5% citrus pulp (PROP). During the experiment (27 days), the piglets were periodically weighed and sampled for a serum biochemical, fecal microbiological, intestine histological, and digestive status analysis. The body weight, apparent ileal digestibility of dry matter (DM), and fecal microbiology were not affected by the treatments (p ≥ 0.05). However, the apparent fecal digestibility of DM was lower for the C- treatment than for C+ (p < 0.05), and the total concentration of volatile fatty acids (VFAs) in feces with C+ was lower than that for the PROC treatment (p < 0.05). The treatments with the probiotic had a higher molar proportion of butyric acid in feces than C+, and it was found that C- reached an intermediate value (p < 0.01). No general effects of diet were found on the histological measures performed on the jejunum and ileum, and in the serum biochemical analysis (p ≥ 0.05), only the concentration of interleukin-8 was lower for the PROC treatment compared to the C-, C+, and PRO treatments (p < 0.05). In conclusion, the intestinal wellness of piglets could be improved with the supplementation of Clostridium butyricum by increasing butyric acid, and this effect was not altered with the inclusion of carob meal or citrus pulp. More studies under commercial conditions are needed, as the effects might be different in more challenging environmental circumstances.

PSXV-22 Effect of inclusion of dried citrus pulp in the receiving supplement for newly received stocker cattle

Citrus pulp is a source of flavonoids which have been found to have antioxidant properties. Thus, the objective of this experiment was to investigate the effects of feeding dried citrus pulp on performance of newly received calves. Crossbred beef heifers (n = 254, initial body weight = 248 ± 5.9 kg) were obtained on 3 dates (block, 8 pens/block). Treatments were: 1) a corn and distillers’ grains based receiving supplement (control) or 2) a receiving supplement that contained 20% dried citrus pulp (replacing a portion of the corn). Upon arrival from regional livestock markets, cattle had access to hay and water and rested overnight then were processed the next day in which they received an identification tag, were vaccinated with a clostridial and a 5-way modified live bovine respiratory viral, dewormed, weighed, branded, and ear notched for detection of persistent infection with bovine viral diarrhea virus. Each truckload was assigned randomly to pens resulting in 8 pens with 9 to 12 heifers/pen. Pens were assigned randomly to 1 of the 2 treatments. Cattle were offered bermudagrass hay and water for ad libitum intake and were offered up to 1.8 kg/day of their appropriate receiving supplement. Overall average daily gain for the 42-day receiving period was increased (P &lt; 0.01) for calves fed the supplement that included dried citrus pulp (1.01 kg/day) compared to the calves fed the control supplement (0.90 kg/day). However, the percentage of calves treated for clinical bovine respiratory disease was increased (P &lt; 0.05) for calves fed the citrus pulp containing supplement (14% morbidity) compared to control calves (7% morbidity). The supplementation of dried citrus pulp to calves improved growth performance, but did not reduce the incidence of clinical bovine respiratory disease during the receiving period; however, clinical morbidity was low for both treatments.

PSIII-3 Metabolizable utilization of energy and protein for egg production by addition of dried citrus pulp and eggshell into diet for laying quails (coturnix japonica)

This study aimed to evaluate the effects of adding 0% (T1), 6% (T2), 12% (T3) and 18% (T4) of a mixture (83% dried citrus pulp (DCP) and 17% eggshell) into a sorghum-soybean meal-limestone based diet for laying quails, on production efficiency and quality of egg. Thirty-two quails were individually housed and randomly assigned (n = 8) to the four experimental diets, during the first 5 week of the laying cycle. Quail LW and feed intake were recorded weekly. Produced eggs were weighed (n = 457) and egg mass production recorded. Proportions of albumen, yolk and shell, egg yolk color, and shell thickness, were determined (n = 55/treatment). On week 5, total excreta of 24 laying quails (n = 6) were collected throughout 96 h, to determine metabolizable utilization of DM, energy, crude protein and ash. Statistical analyses were performed with SPSS® software. Initial and final LW, feed intake and egg production were similar (P &gt;0.05) among treatments. Egg mass was higher (P &lt; 0.05) in T2 than T4. Egg weight of quails fed T1 and T2 was higher than others (P &lt; 0.05). The eggshell of quails fed T2 was thicker (248 vs 236 μm; P &lt; 0.05) than T1. Eggshell proportion of quails fed the mixture was higher (P &lt; 0.05) than in T1 (11.3 vs 10.5%). Yolk proportion of T1 was higher (P &lt; 0.05). The b* parameter was lower (P &lt; 0.05) for T1. Metabolizable utilization of dietary DM (72.1%) and energy (68.8%) of T1 was 13% higher (P &lt; 0.05) than T4, however protein (avg 41.4%) and ash (avg 46.7%) utilization were similar (P &gt; 0.05) among treatments. In conclusion, adding up to 12% of the mixture (83% DCP and 17% eggshell) in quail diets, resulted in similar egg production parameters, and metabolizable utilization of dietary DM, crude protein, energy and ash, however improved thickness of eggshell, compared to the control diet.

Effect of Yeast-Fermented Citrus Pulp as a Protein Source on Nutrient Intake, Digestibility, Nitrogen Balance and In Situ Digestion Kinetics in Nili Ravi Buffalo Bulls

A study was carried out to evaluate the effect of single cell protein (SCP) supplement as a protein source on nutrient intake, digestibility, nitrogen balance and in situ digestion kinetics in four Nili Ravi buffalo bulls. Four iso-caloric and iso-nitrogenous concentrates containing 3, 6, 9 and 12% of Saccharomyces cerevisiae-fermented citrus pulp were formulated. All animals were fed a ration with a concentrate/forage ratio of 50:50. Diets were provided ad libitum twice a day as a total mixed ration in a 4 × 4 Latin Square Design. Each experimental period lasted 3 weeks while the overall study 12 weeks. The first 2 weeks of each experimental period were used as adaptation period while the third week as collection period. Chemical composition of fermented citrus pulp appeared as an excellent source of protein. No significant difference was observed on dry matter intake, digestibility of nutrients and SCP among all the treatments. Moreover, no significant effect was observed on ruminal pH and ammonia nitrogen at different times. Rate of disappearance and lag time of in situ dry matter digestion kinetics remained nonsignificant regardless of SCP percentage. Based on results of similar nutrients intake, nutrient digestibility, and ruminal parameters it is concluded that SCP could be used in the concentrate diet of ruminant up to 12%. Furthermore, the SCP has the potential of an alternative protein source in animal diet formulation.