Scielo RSS <![CDATA[South African Journal of Animal Science]]> http://www.scielo.org.za/rss.php?pid=0375-158920180001&lang=pt vol. 48 num. 1 lang. pt <![CDATA[SciELO Logo]]> http://www.scielo.org.za/img/en/fbpelogp.gif http://www.scielo.org.za <![CDATA[<b>Editorial</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100001&lng=pt&nrm=iso&tlng=pt <![CDATA[<b>Effects of exogenous tannase enzyme on growth performance, antioxidant status, immune response, gut morphology and intestinal microflora of chicks fed grape pomace</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100002&lng=pt&nrm=iso&tlng=pt An experiment was conducted to study the effects of dietary addition of tannase to feed of chicks including grape pomace (GP) on growth performance, antioxidant status, immune response, blood parameters, gut morphology, intestinal microflora, liver function, and histopathological responses. The experimental diets were i) control (corn and soybean diet) (C); ii) C+10%GP; iii) C+10%GP+T1 (500 mg/kg tannase enzyme); and iv) C+10% GP+T2 (1000 mg/kg tannase enzyme). At 10 days old, the bodyweight (BW) and average daily gain (ADG) of the birds fed the diet supplemented with GP was lower compared with the control group. In contrast with the control, supplementation of diets with 10%GP+1000 mg/kg tannase elevated superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and depressed the malondialdehyde (MDA) level in serum. The addition of GP to the chicken diets had a significant impact on the total anti- sheep red blood cells (SRBC) titers and IgG, and IgM antibodies at 21 and 42 days old. The muscularis thickness of the chicken duodenum decreased in the Trial 3 compared with control groups. The inclusion of GP in the chicken diets reduced the concentration of Escherichia coli and increased that of Lactobacillus compared with the control. The results of the present study suggest that the inclusion of up to 10 percent GP in diets did not adversely affect broiler growth performance, and supplementation of tannase improved the antioxidant status and immune responses,and increased the caecal populations of beneficial bacteria in the cecum of broiler chickens. <![CDATA[<b>Meat quality of weaner steers adapted to a diet containing potassium humate in the feedlot</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100003&lng=pt&nrm=iso&tlng=pt The objective of the study was to determine the meat quality responses of weaner steers fed diets containing potassium humate (PH) in a feedlot. Twenty-two yearling male steers were randomly allocated to two treatments: control (n = 11), fed a standard feedlot diet and PH (n = 11), fed a standard diet with added PH (5.8g/kg feed). The steers were housed in individual stanchions, with each steer as the experimental unit. At the end of the feeding trial at Day 112, the steers were slaughtered and the m. longissimus thoracic et lumborum muscle was sampled for meat quality measurements. Results of the study showed that diet had no effect on carcass characteristics and meat quality measurements, apart from meat pH and shear force values. Meat pH decline was more pronounced in the control group and higher shear force values were observed in the control group (6.58 and 4.91 kg) than the PH group (5.12 and 4.14 kg) at Day 1 and Day 7 of measurement respectively. The total intramuscular fat (IMF) was higher (by 16%) in the PH- fed weaner steers compared with the control. With regard to saturated fatty acids (SFA), higher amounts of myristic acid and heneicosanoic acid were observed in the PH-fed steers than in the control. However, the control had higher amounts of eicosatrienoic acid and eicosatetraenoic acid. PH inclusion in steer diets could therefore provide an alternative growth promotant in the production of safe and healthier meat in the feedlot. <![CDATA[<b>Relationship of ewe reproduction with subjectively assessed wool and conformation traits in the Elsenburg Merino flock</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100004&lng=pt&nrm=iso&tlng=pt Subjectively assessed wool and conformation traits are widely used to select breeding ewes and rams in the sheep industry. Data from a Merino flock that is maintained at Elsenburg Research Farm were used to investigate animal model (co)variance components for ewe reproduction traits with subjectively assessed wool and conformation traits. Ewe reproduction traits were assessed at their first lambing opportunity at two years, or over a three-year period from their lambing opportunities at two to four years old. Relationships of ewe reproduction traits with subjectively measured wool and conformation traits were also investigated. All these traits were heritable, with a range from 0.16 ± 0.03 for topline (TOPL) to 0.64 ± 0.04 for woolly face score (WFS). Genetic correlations of number of lambs born (NLB1) with colour (COL), number of lambs weaned (NLW1) with COL and belly and points (BANDP) and total weight of lamb weaned (TWW1) with COL were negative and significant. Significant genetic correlations of ewe reproduction traits over three lambing opportunities were found between number of lambs born (NLB3) and WFS (0.23 ± 0.11) and between total weight weaned (TWW3) and face cover score (FCS) (-0.33 ± 0.16). Among these traits, the noteworthy favourable genetic correlation between total fold score (TOT) and NLB1 suggested that plainer ewes were more reproductive. This is important for the South African Merino industry as plainer sheep are more desirable because of their faster growth and higher lambing percentages and reduced chances of fly strike. Selection for improved ewe reproduction in Merino sheep thus would not result in marked unfavourable correlated responses in most of these subjective wool and conformation traits. <![CDATA[<b>Effects of inulin, carrot and cellulose fibres on the properties of raw and fried chicken meatballs</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100005&lng=pt&nrm=iso&tlng=pt The effects of inulin, carrot, and cellulose fibres (3%, 6%, and 9%) on raw and fried chicken meatballs were studied. Meatball pH, thiobarbituric acid reactive substances (TBARS), and colour values were determined for raw samples in refrigerated storage on the 1st, 5th and 10thdays. The effects of fibres and their various levels on frying characteristics such as yield, diameter reduction, moisture retention, fat absorption, colour and sensory properties of fried chicken meatballs were evaluated. Fibres caused significant differences in the pH and TBARS values of the raw meatballs owing to their sources and levels. They improved colour properties (L: lightness, a: redness, b: yellowness) of the raw and fried samples. In addition, cellulose and carrot fibres affected the yield, moisture absorption, and diameter reduction values of the fried samples positively. In conclusion, the use of fibres in such products can affect product quality positively. The use of 3% inulin, 9% carrot, and 6% and 9% cellulose fibres had more beneficial effects on chicken meatballs. <![CDATA[<b>Comparison of greenhouse gas emissions from Mexican intensive dairy farms</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100006&lng=pt&nrm=iso&tlng=pt The objectives of this study were to compare estimates of greenhouse gas emissions (GHG) as CH4 (enteric-manure), N2O (manure), and CO2 (fuel and energy use), the use of water and soil, the excretion of nutrients in manure, and feed efficiency from Mexican intensive dairy farms. Data from 26 dairy farms were analysed with a multivariable cluster analysis. Three grades of intensifications were identified (low, medium and high). Mathematical models were used to estimate GHG. Feed efficiency (kg milk per kg DMI) was better in high intensive production systems. Enteric methane was identified as the major source of GHG in all types of systems. High intensive dairies generated the lowest emissions of CH4, N2O and CO2 equivalent by unit of product, 18.6 g, 0.12 g and 828 g, respectively. Water footprint was lower in low intensive dairies using 427 L of water/L of milk. Cropland was highest in intensive systems but milk yield per area was better (30,938 kg/ha). Excretions of N, P, and K were lower in intensive dairies per kg of milk, at 13.2, 2.4, and 6.4 g, respectively. As intensification in the dairy system increased feed efficiency (kg milk/kg DMI) was better. Per unit of product (kg of milk), dairies with the highest intensification generated the lowest GHG emissions, nutrient excretion values and land and water use as compared to dairies with medium and low intensification. Increasing intensification and therefore feed efficiency of Mexican dairy systems could help to decrease GHG emissions, natural resources use and nutrient excretion. <![CDATA[<b>Altered tissue mineralization, increased hepatic lipid and inhibited autophagy in intrauterine growth retardation piglets</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100007&lng=pt&nrm=iso&tlng=pt Mineral homeostasis is often disrupted in intrauterine growth retardation (IUGR) infants. Most studies focus on calcium or phosphorus metabolism of IUGR infants via determining serum mineral concentrations instead of tissues. This study was conducted to investigate the effects of IUGR on the mineralization and physiological functions of tissue in a piglet model. Six normal birth weight (NBW) and six IUGR neonatal piglets were slaughtered at 35 days. Mineral concentrations in blood and selected tissues (liver, kidney, lungs, heart, and longissimus dorsi muscle (LDM)), hepatic lipid, mRNA expressions of magnesium (Mg) metabolism, and autophagy were analysed. Results showed that IUGR pigs showed significantly lower phosphorus (P) in LDM, and lower Mg in the liver and LDM, and higher Mg in lungs than NBW pigs. There were no significant differences in concentrations of selenium (Se), calcium (Ca), copper (Cu), aluminium (Al), and lithium (Li) in selected tissues. IUGR pigs had similar mRNA expression of TRPM7 and MagT1 to NBW pigs, but significantly lower expressions of HNF1B and Mrs2 in the liver than NBW pigs. Hepatic triglyceride was significantly increased, and MAP1LC3B expression was significantly decreased in IUGR pigs compared with those of NBW pigs. These result suggested that IUGR pigs had tissue mineralization disturbance, especially for Mg, and liver dysfunction (increased hepatic lipid and inhibited autophagy). Hepatic Mg deficiency might result from increased Mg efflux via reducing HNF1B expression. <![CDATA[<b>Effects of varying sweet lupin dietary inclusion levels on feather classes, leather traits and meat composition of feedlot ostriches</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100008&lng=pt&nrm=iso&tlng=pt The main consumer products derived from ostriches are feathers, leather and meat. Despite progress in optimizing production practices, additional information is still necessary about the value of various raw materials as feed to ensure cost-efficient production. This study aimed to determine the effects of the gradual replacement of soybean oilcake meal with sweet lupin (Lupinus angustifolius) seed in the diet of feedlot ostriches on the feather, leather and meat production characteristics. The chicks received a standard commercial pre-starter ostrich diet, with the trial utilizing 141 ostrich chicks (± 10 chicks per group), beginning with the starter phase (83 days posthatching) and reared until 11 months of age. Five iso-nutritional diets were formulated for each feeding phase (starter, grower and finisher) according to specifications for each phase. In each phase, a control diet (Diet 1, 0% lupin diet (LD)) was formulated using soybean oilcake meal as the sole protein source and Diet 5 (100LD) was formulated to include the maximum amount of sweet lupin according to the specifications for the species and feeding phase. The maximum amount of sweet lupin included in 100LD therefore differs among the three feeding phases. The remaining three diets were formulated by gradually replacing soybean oilcake meal with lupins in the following increments: 100 : 0 (0LD); 75 : 25 (25LD); 50 : 50 (50LD); 25 : 75 (75LD), and 0 : 100 (100LD). There were three replications per treatment, resulting in 15 groups of birds. Feed and water were supplied ad libitum. No differences were found for moisture, crude protein and ash contents of the meat. However, the intra-muscular fat content was significantly influenced by the sweet lupin content of the diet. No differences were found for any of the feather classes that were measured. Regarding leather traits, the treatment diets had no effect on the crust sizes, leather grades, nodule diameters, and nodule densities. Differences were observed for leather thickness and pinhole number. It can be concluded that the sweet lupin inclusion levels evaluated in this study had little influence on leather traits, meat composition and feather classes. <![CDATA[<b>Effects of short and extended fasting periods and cattle breed on glycogenolysis, sarcomere shortening and Warner-Bratzler shear force</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100009&lng=pt&nrm=iso&tlng=pt The effects of short (three hours) and extended (24 hours) feed withdrawal periods and three cattle breeds on muscle energy metabolism, sarcomere length, and meat quality were investigated. Brahman (Br), Nguni (Ng), and Simmental (Sm) bulls were subjected to ante-mortem feed withdrawal of three hours (Br3, n = 10; Ng3, n = 10; and Sm3, n = 10) or 24 hours (Br24, n = 10; Ng24, n = 10; and Sm24, n = 10). M. longissimus was used as the reference muscle for sampling. pH, and temperature was recorded at 1, 2, 3, 6, 9, and 24 hours post mortem. Samples for energy metabolites were removed at 3, 6, 9 and 24 hours post mortem. Glycogen, glucose-6-phosphate and creatine phosphate concentration were determined at each time interval as glycosyl units after hydrolysis. Samples to determine sarcomere length were removed at one and three days post mortem. Homogenates of the samples were placed under a 31,000 magnification microscope and sarcomere lengths were measured. Warner-Bratzler shear force (WBSF) was measured with an Instron meter at 1, 7 and 14 days post mortem. Glycogen was lower for Br24 and Ng24. There were no differences in glucose-6-phosphate, rate of creatine phosphate decline, average sarcomere length, or WBSF for Br24 and Ng24 compared with Br3 and Ng3. There were no differences for WBSF between Br3, Ng3 and Sm3. Glycogen concentration was higher for Sm24 compared with Sm3; glucose-6-phosphate was lower for Sm24 compared with Sm3; and the rate of creatine phosphate decline was higher for Sm24 compared with Sm3. Average sarcomere length was shorter and WBSF was higher for Sm24 compared with Sm3. The effect of prolonged ante-mortem feed withdrawal on tenderness is breed specific. Warner-Bratzler shear force was affected significantly by an extended feed withdrawal period in Simmental cattle only. <![CDATA[<b>A nutritional and economic evaluation of <i>Moringa oleifera</i> leaf meal as a dietary supplement in West African Dwarf goats</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100010&lng=pt&nrm=iso&tlng=pt Moringa oleifera leaves may have the potential to enhance nutritional status, growth performance, and health of ruminant animals when used as part of their diets. However, the nutritional value of the leaves for goats is largely unknown and needs to be investigated. Consequently, eighteen West African Dwarf (WAD) bucks weighing 7.0 ± 0.33 kg were used in a completely randomized design to evaluate the effects of diluting a conventional supplement with three levels of M. oleifera leaf meal (MOLM) on growth performance, haematology, and blood biochemical constituents. The MOLM was included in the commercial supplement at a rate of 0, 50, and 100 g/kg dry matter (DM). Including MOLM in the supplement did not significantly affect weight gain, dry matter intake, and metabolic weight gain of bucks. Packed cell volume (PCV), red blood cell (RBC), haemoglobin concentration (hb), and total protein were not significantly influenced by MOLM inclusion, either. However, blood urea concentration was significantly increased in bucks that were offered MOLM-based diets. All blood parameters, as well as alanine transaminase (ALT) and urea, were within the normal reference ranges for clinically healthy goats. The MOLM-based supplements had significantly lower feed cost per kilogram of weight gain and higher profit per kilogram of gain. It was concluded that diluting the commercial supplement with MOLM up to 100 g/kg DM does not impair the nutritional status, growth performance and health status of the goats while reducing the feed cost per gain. <![CDATA[<b>Expression of ovine ubiquitin C-terminal hydroxylase 1, pH and colour of variety meats from head-stunned Dohne Merino sheep</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100011&lng=pt&nrm=iso&tlng=pt Ubiquitin C-terminal hydroxylase (UCH-L1) has been identified in few transcriptome studies as a biomarker coding for trauma and perception of pain in non-meat species. For the first time, real-time polymerase chain reaction (qPCR) assay was used to quantitate the expression of ovine ubiquitin C-terminal hydroxylase 1 (ovUCH-L1 mRNA) from head-stunned Dohne Merino ewes and lambs presented for slaughter at a high-throughput abattoir. The correlation between ambient environment and quality of variety meats from those ovine species was also determined. The level of ovUCH-L1 mRNA expression found in lambs was high, based on the outcome of qPCR quantification. The effect of head stunning shows that ewes exhibited higher capacity to impede electric insults than lambs. Except for the trachea and heart, ambient conditions had a negative correlation with pH of most variety meats. Similarly, a negative correlation was observed between total colour difference (∆E*) for fillet and dew point. Saturation index of a few variety meats showed a moderate relationship with ambient temperature. Industrially, the results on ambient conditions are important for post-mortem control of pH, colour, and preservation of other physiochemical properties of variety meats. Findings from qPCR quantification indicated that ovUCH-L1 is a novel candidate marker for pain detection in head-stunned ovine species. <![CDATA[<b>Effect of feeding duration of <i>Spirulina platensis</i> on growth performance, haematological parameters, intestinal microbial population and carcass traits of broiler chicks</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100012&lng=pt&nrm=iso&tlng=pt Spirulina platensis is a good candidate as an in-feed antibiotics substitute for broilers. However, its use seems impractical owing to its high price, especially when being administered throughout the whole rearing period. This study aimed to investigate the effects of feeding duration of S. platensis on growth, haematological parameters, intestinal microbial population, and carcass traits of broiler chicks. A total of 288 one-day-old broiler chicks were randomly allotted to one of four groups, including control (basal diet with 0.04% zinc bacitracin) (CONT) and birds receiving basal diet supplemented with 1% of S. platensis for the first seven days (SP-7), for 21 days (SP-21), and for 35 days (SP-35). In this study, treatments had no significant effect on the growth performance of broilers. The caecum relative weight was significantly higher in SP-35 than in CONT and SP-21 birds. The values of haemoglobin, erythrocytes, and haematocrit were significantly lower in SP-35 than in other birds. Compared with CONT, SP-35 birds had significantly lower numbers of leukocytes, lymphocytes, and a lower number of eosinophils. The numbers of coliform were significantly lower in the ileum of SP-21 than in CONT and SP-7 birds. In the caecum, coliform tended to be lower in SP-21 than in other birds. There was no significant difference in the carcass traits of broilers across the groups. In conclusion, the administration of S. platensis for the first 21 days of broilers' life resulted in similar or even better responses than administration of S. platensis or in-feed antibiotics throughout the rearing period. <![CDATA[<b>Optimization of <i>in vitro</i> culture and transfection condition of bovine primary spermatogonial stem cells</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100013&lng=pt&nrm=iso&tlng=pt The present study aimed to optimize the in vitro culture and transfection efficiency of bovine primary spermatogonial stem cells (SSCs). To this end, SSCs were obtained from newborn Holstein bull calves by two-step enzymatic digestion. After enrichment and culture, SSCs were characterized by using alkaline phosphatase (AP) staining and expression of vasa and thy1 genes as specific bovine SSC markers. To evaluate the effect of antioxidants on vitality, colony formation, and the expression of pro- and anti-apoptotic genes of bovine SSCs, various concentrations of vitamin C (5, 10, 25 and 50 µg/mL) and Trolox (a water soluble α-tocopherol analogue) (12.5, 25, 50 and 100 µg/mL) were added to the SSC culture medium. The results showed that SSCs treated with 50 µg/mL of vitamin C or 25 µg/mL of Trolox individually could increase cell viability and colony formation significantly in comparison with other concentrations and the control group. Additionally, the expressions of bax (as a pro-apoptotic gene) and bcl2 (as an anti-apoptotic gene) were significantly lower and higher than the control group, respectively. To optimize the transfection condition, the effective dosages of vitamin C or Trolox, with various concentrations of two transfection reagents (X-tremeGENE HP and Turbofect) and DNA, at day 8 of culture, were studied. Results showed that 1 μl X-tremeGENE HP or 0.5 μl Turbofect and 2 μg of DNA are the best concentrations for transfecting SSCs. However, X-tremeGENE HP expressed more potential for transfecting SSCs in comparison with Turbofect. Besides, no difference was observed between the use of defined doses of vitamin C or Trolox. <![CDATA[<b>Assessment of genetic variation among four populations of Small East African goats using microsatellite markers</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100014&lng=pt&nrm=iso&tlng=pt The majority of goats in Tanzania belong to the Small East African (SEA) breed, which exhibits large phenotypic variation. This study aimed to determine the genetic structure of, and relationships among four populations (Sukuma, Gogo, Sonjo, and Pare) of the SEA breed that have not been studied adequately. A total of 120 individuals (24 from each population) were analysed at eight microsatellite loci. In addition, 24 goats of the South African Boer breed were used as reference. Observed heterozygosity (Ho) ranged from 0.583 ± 0.04 for Sukuma to 0.659 ± 0.030 for Gogo, while expected heterozygosity (He) ranged from 0.632 ± 0.16 for Sukuma to 0.716 ± 0.16 for Boer. Five loci deviated from Hardy-Weinberg equilibrium (HWE) across populations. The mean number of alleles ranged from 4.75 ± 1.58 for Pare to 6.88 ± 3.00 for Sukuma. The mean inbreeding coefficient (F IS) ranged from 0.003 in Sonjo to 0.148 in Sukuma. The differentiation coefficient (F ST)was highest (0.085) between Boer and Sukuma and lowest (0.008) between Gogo and Sonjo. The largest genetic distance (0.456) was found between Sukuma and Boer, while the smallest (0.031) was between Gogo and Sonjo populations. Pare, Gogo, and Sonjo populations, formed one cluster, while Sukuma and Boer populations formed two separate clusters. From the findings, it can be concluded that the SEA goats in this study showed high in population genetic variation, which implies that there is good scope for their further improvement through selection within populations. The Sukuma population, which has fairly high inbreeding, is moderately differentiated from Pare, Sonjo, and Gogo goat populations, which showed a high level of admixture. Conservation and improvement strategies of the goats should be designed with first priority being on Sukuma goats. <![CDATA[<b>Genetic diversity in Zimbabwean Sanga cattle breeds using microsatellite markers</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100015&lng=pt&nrm=iso&tlng=pt Zimbabwe's smallholder land-based livelihoods are dominated by the three local Sanga cattle breeds, namely Mashona, Tuli, and Nkone. A study was carried out to determine genetic diversity and differentiation among conservation populations of these breeds using 16 bovine-specific microsatellite markers. These markers included BM1818, BM1824, BM2113, CSRM60, CSSM66, ETH10, ETH225, ETH3, ILST006, INRA23, RM067, SPS115, TGLA122, TGLA126, TGLA227, and TGLA53. All marker loci contributed to breed differentiation based on the infinitesimal model (F ST), with the most powerful markers being CSSM66 (25%), ETH225 (20.6%), and TGLA122 (13.8%) and the least powerful being RM067 (0.7%), BM1824 (1.0%), and ETH10 (1.1%). Three marker loci (BM1824, ETH225, and ETH3) revealed significant deviations from Hardy-Weinberg equilibrium (HWE) proportions. A total of 119 alleles were observed, ranging from 4 to 11 and averaging 7.4 alleles per locus. Thirty-four of these alleles were unique to specific breeds. Mean (Na) and effective (Ne) numbers of alleles were 5.167 ± 0.302 and 3.462 ± 0.163 alleles per locus, respectively, with no significant differences between breeds. Observed heterozygosity (H O)(0.73) was higher than expected heterozygosity (H E) (0.71), revealing that breeds were in HWE. Global F-statistics F IT, F ST, and F IS gave mean values of 0.059, 0.084 and -0.028, respectively. Overall breed genetic differentiation was moderate (F ST = 8.4%) and significant (P <0.001). Multivariate analyses separated the three breeds completely, and revealed that most of the genetic variation was within breed (92%). The analyses revealed that a significant amount of variation is maintained in these breeds and that they are distinct genetic entities that may be considered for utilization or conservation. <![CDATA[<b>Effects of chitosan addition on growth performance, diarrhoea, anti-oxidative function and serum immune parameters of weaned piglets</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100016&lng=pt&nrm=iso&tlng=pt The present experiment was designed to determine the efficacy of a commercial source of chitosan (CS) to enhance performance, anti-oxidative function, and immune response in weaned pigs. A total of 60 crossbreed piglets (Duroc × Landrace × Yorkshire), with average live bodyweight of 8.85 ± 1.52 kg, were weaned at 28 ± 2 days and randomly assigned to five treatment groups, which were fed maize-soybean meal diets containing 0 (basal diet, control) and 250, 500, 1000, and 2000 mg/kg CS. The experiment lasted for two weeks. Body weight was recorded and daily feed intake was calculated. Faecal consistency was monitored for the overall period. After two weeks, blood samples were collected and anti-oxidative and immune parameters were determined. The results showed that CS improved average daily gain and daily gain: daily feed intake during the experiment. Mean faecal score values for the second week were improved by CS, which showed decreased values compared with the control diet. The CS increased the total antioxidant capacity and the activities of superoxide dismutase, catalase and glutathione peroxidase and the content of reduced glutathione in serum, and decreased the malondialdehyde and cortisol contents of serum. Furthermore, CS increased the levels of serum IL-1β,IL-2 and IgG. These findings suggested that the use of CS improved performance and anti-oxidative function, and regulated the immune response of weaned pigs. <![CDATA[<b>Effects of sesame meal on intake, digestibility, rumen characteristics, chewing activity and growth of lambs</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100017&lng=pt&nrm=iso&tlng=pt Two experiments were carried out to determine ruminal degradability of sesame meal (SSM) and its effects on intake, digestibility, rumen parameters, chewing activity, and lamb performance when it replaced soybean meal (SBM). Degradability of dry matter (DM) and crude protein (CP) were determined with the nylon bag technique using three fistulated Zel ewes. The quickly and potentially degradable DM of SSM was lower, but their degradation rates of DM were similar. The quickly degradable protein in the SSM was greater, but the slowly degradable protein of SSM was lower. Potential degradable protein of SBM was greater. The degradation rate of protein was greater in the SSM. Thirty Zel lambs were assigned to five treatments, namely 1) control diet that contained SBM, and 2), 3), 4) and 5) diets that contained 25, 50, 75, and 100% DM of SSM partially or entirely replacing SBM and part of barley grain. There was no difference in the intakes of DM, CP, ether extract (EE), and non-fibre carbohydrate (NFC) among treatments, but neutral detergent fibre (NDF) intake increased when the SSM inclusion rate was increased. Digestibility of DM and EE, passage rate, and total mean retention time differed, but the digestibility of NDF, CP, and NFC, rumen liquid pH and NH3-N, passage rate, rumen retention time, eating time, rumination, total chewing activity, DM intake, daily gain, feed conversation ratio, carcass yield and characteristics were not different between treatments. Replacing the SBM with SSM in lamb, improved intake, digestibility, and rumen condition, without reduction in performance and carcass composition. <![CDATA[<b>The influence of different dietary energy concentrations on the production parameters of feedlot ostriches</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100018&lng=pt&nrm=iso&tlng=pt Energy is essential for the continuous survival of any living organism. In ostrich diets, energy is usually derived from maize, which is often subject to fluctuations in yield as a result of drought conditions. Therefore, the optimal utilization of energy in the diets of ostriches becomes of paramount importance, but without affecting the performance of the birds negatively. This study was conducted to investigate the influence of five treatment diets, each with a different energy concentration, on the growth performance of 300 slaughter ostriches. Three replications per treatment resulted in 15 camps of ostriches being fed through the four feeding phases from pre-starter to starter, then grower, and finally finisher. A high mortality rate was experienced during the pre-starter phase, while the chicks were still young. Significant differences were found among the live weights of the birds after the pre-starter phase, with birds that consumed the middle diet (Diet 3) being the heaviest, at an average of 22.3 ± 0.33 kg. However, by the end of the trial, these differences were not significant. This was reflected in the production parameters, namely dry matter intake (DMI), average daily gain (ADG) and feed conversion ratio (FCR). Differences were found only in the pre-starter phase in ADG, with Diet 3 displaying the highest gain per day of 216.0 ± 8.08 g. Thus, in this study, dietary energy above and below the predicted optimum (Diet 3) seemed to have little influence on the performance of the ostriches, but results may have been affected by the above-average mortalities. <![CDATA[<b>Feed preference of grower ostriches consuming diets differing in <i>Lupinus angustifolius</i> inclusion levels</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100019&lng=pt&nrm=iso&tlng=pt Feed costs contribute the largest proportion of the input costs of slaughter birds in an intensive ostrich production unit. Alternative, cheaper feedstuffs, such as lupins (sweet and bitter cultivars), were therefore evaluated to determine the optimal lupin inclusion level in ostrich rations without affecting feed preference and intake. Sixty South African Black ostriches were randomly divided into ten paddocks of six birds per paddock. Three trials, with five different experimental diets, were conducted to investigate the diet preference of grower ostriches in a free-choice system. Feed and water were supplied ad libitum. The position of the diets in the successive paddocks was varied by rotating the five feed troughs in a clockwise direction, but within each paddock the position of each feeder and diet stayed the same throughout the three trials. In the first two trials, sweet (trial 1) or bitter (trial 2) lupins replaced soybean oilcake meal to have 0, 7.5, 15, 22.5, and 30% lupin inclusion levels in the diet. In trial 3 the soybean oilcake meal was replaced with either sweet or bitter lupins to have dietary inclusion levels as follows: 0% lupins, 15% sweet, 15% bitter, 30% sweet, or 30% bitter. The daily intake per group for each diet was monitored over a period of five days each. The average initial body weight of the birds was 73.6 ± 0.5 kg. No interaction was found between day and diet for the three trials and dry matter intake (DMI) did not differ between the five treatments for any of the three trials. In the second trial the birds tended to show a preference for the 7.5% bitter lupin inclusion level and discriminated against the 15% and 30% bitter lupin inclusion levels. Regression analysis of DMI on lupin inclusion rates revealed no significant trends. In conclusion, the study revealed that soybean oilcake meal can be replaced in the diets of grower ostriches by sweet lupin inclusion levels up to 30%, without any significant detrimental effect on diet preference and feed intake. <![CDATA[<b>Effects of supplemental seminal plasma on cryopreserved boar sperm quality</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0375-15892018000100020&lng=pt&nrm=iso&tlng=pt To analyse the effects of supplemental autologous seminal plasma on boar semen quality before freezing and after thawing, thirty ejaculates were collected from six Pietrain boars. The main factors of a 2 x 2 x 2 factorial arrangement of treatments were Beltsville thawing solution (BTS), seminal plasma before freezing, and seminal plasma after freezing-thawing. The percentage of acrosome-intact sperms was reduced by semen dilution. There were no interactions of main factors. The addition of seminal plasma to semen before freezing did not affect semen quality, but the addition of seminal plasma after freezing-thawing increased the percentage of acrosome-intact sperm. This approach indicates that the addition of seminal plasma to boar semen after freezing-thawing improves semen quality.