Scielo RSS <![CDATA[South African Journal of Animal Science]]> vol. 48 num. 4 lang. pt <![CDATA[SciELO Logo]]> <![CDATA[<b>Effects of non-steroidal growth implant and dietary zilpaterol hydrochloride on growth and carcass characteristics of feedlot lambs</b>]]> The effects of steroidal growth implants alone or in combination with β-adrenergic agonist feed additives have not been studied thoroughly in mutton sheep in South African feedlot conditions. This study investigated the effects of a non-steroidal growth implant zeranol (Ralgro®), alone or in combination with zilpaterol hydrochloride (Zilmax®), on growth performance, carcass characteristics, and selected meat quality traits in 160 SA Mutton Merino ram lambs fed in a commercial feedlot. The experimental design consisted of two Ralgro treatment groups x two Zilmax treatments x two Zilmax feeding periods x 20 animals per treatment group. Lambs were randomly allocated to eight treatment groups, of which one half were implanted with Ralgro after arrival, followed by feed supplementation with Zilmax at two Zilmax feeding periods during the finisher phase, compared with negative control treatments (e.g. no Ralgro or Zilmax; Ralgro + no Zilmax; or no Ralgro + Zilmax). All lambs were fed the grower ration traditionally used by the commercial feedlot, which contained 16.89% crude protein (CP) and 2.94 Mcal/kg dry matter (DM). Zilmax was supplemented in the feed at 40 mg per animal per day and fed for 18 days or 25 days, plus three days withdrawal. Lambs that did not receive the Zilmax treatment were fed the basal diet without Zilmax feed supplementation. Ralgro significantly increased average daily gains (ADG) and cold carcass mass (CCM) of lambs. Lambs supplemented with Zilmax during the finisher phase had higher ADG, greater CCM and increased dressing percentage by ca.1.1% compared with those in the control group. Lambs fed Zilmax for 25 days had higher CCM than those fed for 18 days. The duration of the Zilmax treatment also decreased hide weight, fat thickness and shear force values (tenderness). Zilmax increased ADG and CCM in lambs, particularly if combined with Ralgro implants during the growing phase. The results from this study indicate that the combination of Ralgro implants with Zilmax feed supplementation during the finisher phase had additive effects and increased ADG and CCM of feedlot lambs. <![CDATA[<b>Use of polyethylene glycol to improve the utilisation of leguminous leaf meals in pigs: A review</b>]]> The use of leguminous leaf meal as feed ingredients for pigs needs to be intensified and improved. Leguminous trees and shrubs are valuable sources of protein, amino acids, and dietary fibre for pigs. Leguminous leaf meals are abundant in the tropical regions and their use as alternate protein-rich feed ingredients for pigs is promising. In tropics, climate change and vegetation management practices have certainly increased the availability of shrub legumes compared to grasses. There is, therefore, a need to resort on harnessing abundant and cheap feed resources to cope with environmental changes and rise of feed prices. Leguminous leaf meals are invaluable feed ingredients for pigs because of their relatively high crude protein and they are highly available. The leguminous leaves also thrive in, and tolerate, adverse climatic and soil conditions. However, their utilisation is limited by presence of polyphenolic compounds, particularly condensed tannins that inhibit their efficient use by pigs. Other challenges for the utilisation of legume-based leaf meal diets are the presence of thorns and high fibre content. If leguminous leaf meals are included in the diet beyond optimum levels, polyphenolic compounds can suppress appetite, promote feed refusal, reduce digestibility, and can induce toxicity in pigs. This warrants investigation on the use of tannin-binding agents (TBA) to improve nutrient utilisation of leguminous leaf meal-containing diets fed to pigs. The inclusion level of polyethylene glycol (PEG) in livestock diets has a huge potential to neutralise negative effects of undesirable polyphenolic compounds. Therefore, the current review aimed to assess the potential of PEG to inactivate tannin and amount of PEG to include for optimum pig performance. <![CDATA[<b>Effects of fermented bamboo vinegar liquid on growth performance, nutrient digestibility, faecal <i>Escherichia coli </i>concentration and ammonia emissions in growing pigs</b>]]> Fermented bamboo vinegar liquid (FBVL) was prepared through liquid fermentation of bamboo vinegar with multispecies probiotics, and its effect on growing pigs was investigated. A 42-day feeding trial with 84 growing pigs (28.0 ± 0.08 kg) was conducted to evaluate the effects of FBVL on growth performance, nutrient digestibility, faecal Escherichia coli concentration and faecal ammonia emissions. Pigs were randomly distributed to one of four dietary treatments, namely control, CTC (0.003% chlortetracycline), FBVL 0.2%, and FBVL 0.4%. Overall, the final weight and daily weight gain of the pigs in the CTC group were higher than that of pigs in the control group. Dietary supplementation with 0.4% FBVL reduced the feed intake of growing pigs, whereas the feed conversion ratio (FCR) was lower in the CTC supplemented group. The dry matter digestibility was higher in pigs fed CTC and 0.2% FBVL diets, and crude protein digestibility was improved in all treatment groups compared with control. The faecal E. coli numbers were reduced in response to CTC and 0.4% FBVL supplementation. Faecal ammonia emissions were reduced by dietary supplementation with CTC and FBVL at weeks 1, 2 and 3. In conclusion, dietary FBVL supplementation increased nutrient digestibility and reduced faecal E. coli population and ammonia emissions without negative effects on growth performance. <![CDATA[<b>Effects of air temperature on physiology and productive performance of pigs during growing and finishing phases</b>]]> Thirty-six castrated male pigs were used to determine the influence of thermal environment and reduction of consumption on performance and carcass composition. Animals were housed in two climate chambers. In one, animals were in thermal comfort (TN) (22 °C), and in the other, pigs were under heat stress (HS) (34 °C). Animals were distributed in a randomized block design, making three treatments (TN, HS and animals in thermal comfort with food consumption paired with that observed in HS (PFTN)), with six replicates and two animals per experimental unit. Data were obtained on performance and carcass composition. The weight gains of HS and PFTN animals were reduced by 40.5% and 34.7%, respectively, reflecting a reduction of 13.2% in the final weight of PFTN animals. Triiodothyronine concentration was not affected by heat, but there was an increase in lymphocyte numbers in PFTN animals. The HS and PFTN animals showed lower hot carcass weight. However, there were no effects on hot carcass yield and relative weights of heart, lung and spleen. Heat stress compromised performance. The negative effects of high temperature on pigs include reduction in feed intake and changes in physiology. <![CDATA[<b>Effect of lactation stage and milking frequency on milk yield from udder quarters of cows</b>]]> The aim of the study was to analyse daily milk yield from udder quarters of automatically milked primiparous and multiparous cows during lactation and with changing milking frequency. The daily milk yield of udder quarters was higher in multiparous than in primiparous cows. At the same time, differences were observed, especially in front and rear quarters, and also in left and right quarters. The front quarters (LF and RF) of primiparous cows produced an average of 6.75 and 6.71 kg milk, and those of multiparous cows by 0.78 and 0.51 kg milk more, respectively. Higher daily milk yield was characteristic of rear quarters: 8.22 kg (left) and 7.71 kg (right) in primiparous cows, and 10.06 and 10.47 kg in multiparous cows, respectively. With advancing lactation (from <100 to &gt;300 days), the milk yield of all quarters was found to decrease. The lowest decrease was in left front quarters (by 3.40 kg) and the highest in right rear quarters (by 4.35 kg). This relationship was most evident in cows entering lactation (in the first lactation period of <100 days). As milking frequency increased, the milk yield of individual quarters increased markedly. In front quarters, left and right quarters showed similar milk yields for milking frequency of less than 2.50 times/day and more than 2.80 times/day. A similar relationship was observed for rear quarters. The contribution of front and rear quarters to daily production was 45.8-54.2% in primiparous cows and 41.8-58.2% in multiparous cows. <![CDATA[<b>Effect of energy sources on ovarian follicular dynamics and oestrous activity of Holstein cows</b>]]> The objective of the study was to evaluate the effects of three nutritional treatments, which differed in energy level and source, on preovulatory follicles, number of follicles and oestrous activity in dairy cows. Twenty two Holstein multiparous cows from the Elsenburg herd were used in this study. After parturition, cows were kept on kikuyu-ryegrass pastures on an ad libitum basis, and allocated to various levels and types of concentrate supplements, which differed in starch and fat contents. The control group received 7 kg/day of a control concentrate, and the treatment groups each received 12.6 kg/day of concentrate. The concentrates contained high starch-low fat (HSLF) and high starch-low fat/low starch-high fat (HSLF-LSHF) levels. The supplement in treatment HSLF was a glucogenic concentrate using maize as the energy source. The supplements in treatment HSLF-LSHF were a combination of a glucogenic concentrate, which was offered for the first 60 days in milk (DIM), similar to treatment HSLF, followed from 61 DIM by a lipogenic concentrate using wheat bran and calcium (Ca) salts of long-chain fatty acids as the energy sources. At 80 ± 10 DIM, cows were synchronized with an Ovsynch protocol without being inseminated before the ultrasonography observation. While they were detained in a shaded neck clamp, cows were assessed individually with an ultrasound scanner every three days for ovarian measurements and follicular activity until the subsequent oestrus. Results showed that ovarian and follicular measurements and the numbers of follicles in various follicle size classes were similar between nutritional treatments. However, the total ovarian follicular counts were significantly higher in cows that received the HSLF and HSLF-LSHF treatments, compared with their counterparts in the control group (i.e. 7.23 ± 0.22, 7.21 ± 0.14 and 6.53 ± 0.19, respectively), through possible improvement in nutritional status. Further research is required to investigate various energy levels and sources that enhance the viability and the quality of the oocyte ovulating from the dominant follicle and improve the intensity and length of the oestrous expression in dairy cows. <![CDATA[<b>Effects of energy levels and sources on plasma metabolites and live weight of Holstein cows</b>]]> The objective of the study was to evaluate the effects of nutritional treatments, which differed after calving, on energy levels and sources on plasma metabolite profiles and live weight (LW) changes as an indication of the nutritional status in Holstein cows. During the dry period, pregnant heifers (n = 69) and dry cows (n = 153) from Elsenburg Research Farm were maintained under similar feeding and management conditions. After parturition, cows had ad libitum access to cultivated irrigated kikuyu-ryegrass pastures, and were assigned to three concentrate groups, according to calving date, parity, LW and the milk yield of their previous lactation. The groups were supplemented with various levels and types of concentrate, of which the energy was provided by starch and fat. The control group was offered 7 kg/cow/day of a control concentrate supplement for both primiparous and multiparous groups, while concentrates in treatment groups were fed at 11.6 and 12.6 kg/cow/day for primiparous and multiparous groups, respectively. The control supplement was a maize-based concentrate, which contained low levels of starch. The concentrate components of the treatments consisted of high starch-low fat (HSLF) and a high starch-low fat/low starch-high fat (HSLF-LSHF) combination. The HSLF supplement was a glucogenic concentrate, which contained maize as the energy source. The HSLF-LSHF supplements consisted of a glucogenic concentrate, which was offered for the first 60 days in milk (DIM) as per the HSLF treatment, and was followed from 61 DIM with a lipogenic concentrate containing wheat bran and calcium (Ca) salts of long-chain fatty acids as the energy sources. The results showed that all cows mobilized their body fat reserves, as was evident in changes in plasma non-esterified fatty acids (NEFA) before and after calving. Postpartum plasma NEFA and β-hydroxybutyrate (BHB) did not differ significantly between nutritional treatments in multiparous cows. However, the postpartum levels of plasma NEFA and BHB were significantly higher for the control, indicating a status of advanced negative energy balance (NEB) and possible subclinical ketosis compared with HSLF and HSLF-LSHF treatments in primiparous cows. Postpartum plasma urea levels decreased significantly in both primiparous and multiparous animals in the control group, compared with the HSLF and HSLF-LSHF groups. As affected by time, postpartum LW was significantly lowest and LW loss was significantly highest in cows that received the control supplements compared with HSLF and HSLF-LSHF supplements for primiparous and multiparous cows. In addition, LW lossnadir and the number of days to reach it significantly increased in primiparous cows that received the control concentrate, compared with those of the HSLF and HSLF- LSHF treatments. However, this trend was not observed for multiparous cows. The findings of this study showed that HSLF and HSLF-LSHF treatments improved the nutritional status, as was evident in the reduced extent of NEB and limited LW loss of dairy cows, compared with those in the control group. <![CDATA[<b>Meat production characteristics of Turkish native breeds: I. Fattening, slaughter and carcass traits of lambs</b>]]> The present study was conducted to determine the slaughter and carcass traits of male lambs of the Akkaraman (A), Morkaraman (M), Awassi (IW), Karayaka (KR), Kivircik (KV) and Middle Anatolian Merino (MAM) sheep breeds. Fattening of all lambs started when they were at 90 days at weaning and finished when they reached bodyweight of 40 kg. The cold dressing percentage of lambs of A, M, and IW breeds were significantly lower than those of KV, KR and MAM. Fat depth and muscle area were significantly greater in KV and MAM lambs than those of the other breeds. There were significant differences among breeds in shoulder, leg and lean weights. Weights of back loin in KV and MAM lambs were significantly greater than those of the other breeds. The highest values for carcass fleshiness were obtained in MAM and IW lambs, but they had a significantly lower carcass fatness score. There were significant differences among the breeds in carcass compactness and leg conformation. The results of the present study indicated that A and MAM breeds could be recommended for desirable carcass characteristics. <![CDATA[<b>Effect of various levels of isoflavone aglycone-enriched fermented soybean meal on redox status, serum hormones and milk quality in ewes</b>]]> The study investigated the effects of various levels of isoflavone aglycone-enriched fermented soybean meal (FSBM) on the redox status, serum hormones and milk quality of ewes from late pregnancy to early lactation. Twenty Chongming White ewes were chosen and divided into four treatment groups (n = 5): basal diet without FSBM (CON); basal diet with 2% (FSBM2); 4% (FSBM4); and 6% FSBM (FSBM6) replacing equal amounts of soybean meal (SBM). At parturition, maternal serum, the placenta and colostrum were collected. At day 21 of lactation, maternal serum and milk were collected. Results showed that, compared with CON, feeding ewes with FSBM6 reduced the concentrations of hydrogen peroxide (H2O2) and 8-hydroxy-2-deoxyguanosine (8-OHdG), and increased the activity of superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) concentration in the placenta. At parturition and day 21 of lactation, the serum SOD activity and T-AOC concentration in FSBM4 and FSBM6 were higher than those in CON. Furthermore, the concentration of serum 8-iso prostaglandin (8-ISO-PGF2a) was markedly lower in FSBM6 than in CON. Serum prolactin (PRL), insulin-like growth factor 1 (IGF-1) and epidermal growth factor (EGF) concentrations were increased in FSBM4 and FSBM6 compared with CON. PRL concentration was increased in FSBM2. FSBM4 increased the levels of fat, protein, lactose, IgA, IgG and IgM in colostrum and milk. In conclusion, feeding ewes with FSBM from late pregnancy to early lactation seemed to increase maternal and placental anti-oxidative capacity, and improve serum hormones and milk quality. Considered overall, the level of 4% supplementation is recommended. <![CDATA[<b>Effects of protein sources on performance, carcass composition, blood parameters and meat quality in Charolais heifers</b>]]> The aim of the present study was to evaluate the effects of feeding faba bean and sweet lupin as alternative protein sources to soybean on productive performance, blood parameters, carcass composition, and chemical-physical characteristics of meat and its fatty acid (FA) profile in Charolais heifers. Twenty-four heifers were divided into three homogenous groups and fed with durum wheat straw and three iso-energetic and isonitrogenous pelleted complete diets containing 14% (on as-fed basis) soybean meal; 28% faba bean; and 20% sweet lupin seed. The animals were slaughtered after a 168 day feeding period, and the Longissimus lumborum muscle was sampled for meat quality measurements. The feed conversion index was better in the heifers fed faba bean compared with the soybean treatment group (6.71 versus 7.17). No differences were found among treatment groups in productive performance, slaughtering data and physical features. The concentration of linoleic acid in the meat of the soybean group differed significantly from that in the lupin group (2.38 versus 2.11%). Feeding lupin seed increased the concentrations of C20:3 n-6 (0.09%) and C20:4 n-6 (0.20%) in meat significantly, compared with the soya- and faba bean treatments (0.06-0.07% and 0.12-0.13%, respectively). No differences were found among groups for blood parameters, except for urea concentration, which was lower in the lupin group compared with the concentrations in the serum of heifers receiving the soya bean treatment (31.29 as opposed to 37.56 mg/dL). In conclusion, since faba bean and lupin seed did not affect any of the parameters negatively, these legume grains can be included successfully as alternative protein sources in beef cattle diet. <![CDATA[<b>Productive aspects of pigs fed forage cactus silage associated with feed restriction</b>]]> This study aimed to evaluate the use of silage of forage cactus (Opuntia ficus-indica Mill) in diets for finishing pigs. Two experiments were conducted: the first for digestibility and the second for performance. In the performance trial, the quantitative levels of feed restriction (0%, 10%, 20%, and 30%) were evaluated, which were associated with the supply of forage cactus silage. Forage cactus silage presented 2463.59 and 2456 kcal/kg of digestible and metabolizable energy, respectively. The feed restriction levels associated with the supply of forage cactus silage influenced feed intake, weight gain and final weight negatively, but did not affect feed conversion. Carcass absolute weight was influenced negatively. However, the yield of carcass and cuts and the amount of meat in the carcass were not influenced. With the increase in feed restriction, there was a decrease in duodenal mucosa thickness, intestinal glands, liver glycogen storage and the occurrence of inflammation in the submucosa and intestinal mucosa. Forage cactus silage is not accepted well by animals. The restriction up to 30% of balanced feed did not affect feed conversion, yield of carcass and cuts and economic viability. However, levels over 10% affected intestinal health. <![CDATA[<b>Short-terrn liquid storage of ram semen in various extenders</b>]]> The aim of this study was to investigate the effects of three extenders on ram sperm quality after short-term liquid storage (24 hours' holding time). The study included 20 crossbred rams (Pirot Pramenka x Wurttemberg x Ile de France), 12 months old. Animals were housed at the experimental sheep farm of the Institute for Animal Husbandry in Belgrade, Serbia. Semen was collected through electro ejaculation. The ejaculates were obtained from single services and routine field analysis of the semen was performed immediately after the collection. The semen was split and diluted with three extenders, namely Optidyl®, Andromed and ultrahigh temperature processed (UHT) milk, in ratios of 1 : 50 or 1 : 100. The ejaculates were examined for sperm motility variables (sperm cell motility percentage, the progressive motility percentage, curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), sperm linearity (LIN), straightness (STR), amplitude of lateral sperm head displacement (ALH), beat cross frequency (BCF) and circular tracks), and sperm morphology (live sperm percentage, percentage of normal sperm forms with intact acrosome, percentage of abnormal sperm forms and total damaged acrosome) by computer-assisted sperm analysis (CASA) and classic sperm cytology after supravital eosin/nigrosine/trypan blue staining, respectively. It was observed that the type of extender used in diluting ram semen is an important factor in the successful short-term liquid preservation (at 4 °C) of ram spermatozoa. In conclusion, this study showed that egg yolk (Optidyl) and soybean (Andromed)-based extenders gave better results of both sperm morphology and sperm motility parameters compared with UHT milk. <![CDATA[<b>Partial replacement of soybean meal with pumpkin seed cake in lamb diets: Effects on carcass traits, haemato-chemical parameters and fatty acids in meat</b>]]> The composition of lamb diets has an effect on production traits and meat quality, especially fatty acid proportions. Recently, in organic farming, soybean meal has frequently been replaced with feedstuffs that are rich in protein. The aim of the present study was to determine the effects of partial replacement of soybean meal with pumpkin seed cake on carcass traits, biochemical parameters and fatty acids of lamb meat produced in organic farming. The research was carried out on 70-day-old lambs of the Merinolandschaf breed. Thirty-six lambs were grouped by gender, and allotted to three treatment groups, which were given one of the three diets: control diet with no pumpkin seed cake; a diet in which 10% of soybean meal was replaced with 10% pumpkin seed cake; and a diet in which 15% of soybean meal was replaced with 15% pumpkin seed cake. The experimental feeding period was 30 days. Hay and water were provided ad libitum. Differential blood tests and haematological parameters were determined, and the concentrations of minerals and biochemical parameters, and enzyme activity were ascertained in blood serum. Carcass traits and lamb meat colour did not differ among dietary treatments. Significant differences were observed in the concentrations of some biochemical parameters, which indicated good energy and protein balance, and changes in fat metabolism that did not impair antioxidant status. Compared with the control, the concentration of linoleic acid (C18:2 n-6) was higher in diets containing 10% and 15% of pumpkin seed cake replacements. The results indicated that partial replacement of soybean meal with 10% or 15% of pumpkin seed cake could be implemented in lamb feeding in organic farming without major changes in carcass traits, haemato-chemical parameters and the fatty acid profile in meat. <![CDATA[<b>Digestible threonine and its effects on growth performance, gut morphology and carcass characteristics in broiler Japanese quails <i>(Coturnix coturnix japónica)</i></b>]]> Threonine is the third limiting amino acid in corn-soy-based poultry diets and has an important role in body and intestinal development of chicken. Although work on threonine (Thr) in chicken is well established, information about the effects of digestible threonine (dThr) on quail performance is limited. Therefore, the current study was designed to determine the impact of increasing levels of dThr on growth performance, feed conversion ratio (FCR), gut health and carcass characteristics in meat-type quails. A total of 324 mixed-sex day-old quail were randomly allocated to three treatments with six replicates per treatment and 18 birds per replicate. There were three dietary treatments, namely control (C) with recommended levels of dThr according to the Brazilian Tables guidelines for Japanese quails: 10% dThr (C diet supplemented with 10% more dThr) and 20%dThr (C diet supplemented with 20% more dThr). At day 35 of the experiment, three birds from each pen were slaughtered. A duodenal sample was collected and preserved to evaluate gut health. The carcass characteristics were determined from the slaughtered birds. Total feed intake and average daily feed intake were higher in the C treatment than in 10% dThr. Final bodyweight (BW), weight gain and average daily gain (ADG) increased linearly. The birds fed diets supplemented with 20% extra dThr had the highest final weight and bodyweight gain (BWG) compared with those birds that were fed on C and 10% dThr supplemented diets. Feed conversion ratio was improved in 10% dThr compared with the C birds. Villus height (VH) was similar among treatments. The highest crypt depth (CD) was observed in C, followed by 10% dThr and 20% dThr. The birds fed 20% dThr had higher VH:CD than 10% dThr. The birds in the C treatment had lowest VH:CD. Carcass weights with and without giblets were higher in the 20% dThr than in the 10% dThr and C treatments. Breast mass yield (BMY) was greatest in 20% dThr compared with C and 10% dThr. It may be concluded that supplementation of Thr higher than the requirements referred to in Brazilian Tables improves growth performance and gut health of meat-type quail. <![CDATA[<b>Performance, water intake, carcass characteristics and intestinal histomorphology of broilers supplemented with phytase</b>]]> A 32-day experiment was conducted to study the effects of supplementation of phytase enzyme, Ronozyme® HiPhos (DSM Nutritional Products, Basel, Switzerland), on the production parameters, water intake, intestinal histomorphology, carcass characteristics and bone mineralization of broiler chickens. A total of 1920 one-day-old Cobb 500 broilers were randomly allocated to one of three treatments, each comprising eight replicate cages (eight replications per treatment) with 80 birds per cage. Dietary treatments were created using a standard commercial diet as the positive control (CON); reducing the nutrient content of the CON diet with values similar to the matrix values of 1500 FYT (phytase units) Ronozyme® HiPhos to create the negative control diet (NEG); and supplementing the NEG diet with 1500 FYT/kg Ronozyme HiPhos to create the phytase diet (HiPhos). Supplementation of the NEG diet with HiPhos significantly improved average daily gain (ADG), feed conversion ratio (FCR), bodyweight (BW) at slaughter and the European production efficiency factor (EPEF) of broilers compared with those in the NEG treatment group, but had no effect on total feed intake, water intake, villi height, crypt depth, dressing percentage, portion yields, pH of the meat or colour of the meat. Fat-free bone ash percentage and tibia breaking strength of broilers in the HiPhos treatment group were intermediate to broilers in the NEG and CON treatment groups. Results from the study proved that broilers could be supplemented with HiPhos phytase without detrimental effects on growth parameters, bone mineralization, carcass characteristics and water intake. <![CDATA[<b>"Male effect" and "temporary weaning" in synchronization of post-partum ovarian activity in Pelibuey ewes</b>]]> To evaluate the response of the "male effect" and "temporary weaning" on the synchronization of postpartum ovarian activity in Pelibuey ewes, an experiment was carried out using 78 Pelibuey ewes with suckling lambs. The ewes were separated from their offspring for 48 hours and randomly assigned to one of four treatments derived from the arrangement of two factors, "male effect" and "temporary weaning", each at two levels. Treatments were: T1 (n = 20) control ewes, without "male effect" and without "temporary weaning"); T2 (n = 19) ewes without "male effect" and with "temporary weaning"; T3 (n = 20) ewes with "male effect" and without "temporary weaning"; and T4 (n = 19), ewes with "male effect" and with "temporary weaning". The response to oestrus, return to oestrus, gestation rate and lambing rate were analysed using logistic regression. The onset of oestrus was analysed using survival curves. No significant differences were found for lambing rate and prolificacy among treatments. "Temporary weaning" (T2) and "male effect" (T3) did not influence the response to oestrus, rate and duration of return to oestrus, or gestation rate and fertility, and was similar to the control group (T1). The interaction of "male effect" with "temporary weaning" (T4) increased the response to oestrus, reduced the rate and duration of return to oestrus, and the gestation rate, but increased fertility. Synchronizing post-partum ovarian activity with "male effect" and "temporary weaning" reduces the onset of oestrus and the rate of return to oestrus, but increases the response to oestrus and fecundity in Pelibuey ewes. <![CDATA[<b>Effects of three slow-release urea inclusions in rice straw-based diets on yearling Bali bull performances</b>]]> The effects of slow-release zinc-urea complexes (ZnU), urea-impregnated zeolite (UZ) and zinc-urea-impregnated zeolite (ZnUZ) on the performance of yearling Bali bulls were assessed using 20 Bali bulls (145.3 ± 2.5 kg bodyweight (BW)), which were allocated to five treatments and four replications in a completely randomized design. The treatments were: Diets supplemented with no urea (NU) and with urea (U), ZnU, UZ and ZnUZ. The results of the in vivo study revealed that both ZnU and UZ might replace urea effectively by increasing feed intake. Moreover, substituting urea with ZnU, UZ or ZnUZ increased crude protein total tract apparent digestibility whereas ZnU or UZ replacing urea, improved fibre total tract apparent digestibility. Furthermore, inclusion of UZ in the diet improved live weight gain and feed efficiency in Bali bulls above that of the U and NU diets. Thus, the inclusion of ZnUZ in rice straw-based diets showed slow-release urea had positive impacts on feed intake and nutrient digestibility, and increased the efficiency of feed utilization in Bali bulls. <![CDATA[<b>Prediction of solid digesta passage rate using liquid passage rate as one of the input variables in ruminants</b>]]> This study ascertained the influence of liquid passage rates on solid digesta passage rates and the possibilities of simultaneous prediction of solid and liquid passage rates in ruminants. Artificial neural networks were used to develop models of solid and solid-plus-liquid passage rates. Studies that reported fractional passage rates, class and body mass of ruminants were included in the dataset. Animal and feed factors that affect the rate of passage were identified. The database had observations of domestic and wild ruminants of variable body mass from 74 (solid using predicted liquid passage rate) and 31 (solid using observed liquid passage rate) studies. Observations were randomly divided into two data subsets: 75% for training and 25% for validation. Developed models accounted for 76% and 77% of the variation in prediction of solid passage rates using predicted and observed liquid passage rate as inputs, respectively. Simultaneous prediction accounted for 83% and 89% of the variation of solid and liquid passage rates, respectively. On validation using an independent dataset, these models attained 45% (solid using predicted liquid), 66% (solid using observed liquid), 50% (solid predicted with liquid) and 69% (liquid predicted with solid) of precision in predicting passage rates. Simultaneous prediction of solid and liquid passage rate yielded better predictions compared with independent predictions of solid passage rate. Simultaneous prediction of solid and liquid passage rates accounted for more variation compared with independent predictions of solid rates. Inclusion of liquid passage rate as an input variable gave better predictions of solid passage rates. <![CDATA[<b>Response in nutritionally related blood metabolites, carcass traits and primal pork cuts of slow growing Windsnyer pigs fed on varying levels of potato hash silage</b>]]> The response of Windsnyer pigs to diets containing varying levels of potato hash silage in nutritionally related blood biochemistry, carcass traits and primal pork was estimated. Thirty-six growing clinically healthy male Windsnyer pigs with an initial weight of 36 kg ± 4.89 (mean ± standard deviation (SD)) were randomly assigned to six experimental diets containing 0, 80, 160, 240, 320, and 400 potato hash silage g/kg dry matter (DM). Experimental diets were derived from mixing a summit diet containing no potato hash silage and a dilution diet containing 400 g potato hash silage/kg in various proportions. Pigs were allowed ad libitum access to diets and water. There was no relationship between inclusion levels of potato hash silage and albumin: globulin ratio, total protein, and uric acid. As inclusion levels of potato hash silage varied, there was a positive linear relationship between silage and albumin concentration. Globulin concentration had a positive quadratic relationship with the inclusion of potato hash silage. Inclusion levels of potato hash silage resulted in a positive quadratic relationship in alkaline phosphatase. There was a negative linear response in warm carcass weight and cold carcass weight to inclusion levels of silage. A negative linear response was observed in dressing percentage. Different inclusion levels of potato hash silage caused a positive quadratic relationship in cooler shrink. There were negative linear relationships between inclusion of potato hash silage with shoulder fat, carcass length and backfat thickness. There was a negative linear relationship between eye muscle area and inclusion level of ensiled potato hash. There was a positive quadratic relationship between hindquarter length (HQL) and inclusion levels of silage. The observed linear relationship between hindquarter circumference (HQC) and inclusion levels of potato hash silage was negative. There is a need to predict the optimum inclusion level of potato hash silage without compromising the healthiness and carcass yield of pigs. <![CDATA[<b>Production and slaughter performance of ostriches fed full-fat canola seed</b>]]> Full-fat canola seed (FFCS) is a locally produced alternative protein source that has potential for inclusion in the diet of ostriches. Chicks aged 84 days and weighing 24.7 ± 0.36 kg were fed five iso-nutritional diets with varying levels of FFCS. Birds were fed until slaughter at 309 days old (93.2 ± 1.82 kg). In each feeding phase, FFCS replaced soybean oilcake meal incrementally (0%, 25%, 50%, 75% and 100% of protein source). Dry matter intake (DMI) during the grower phase was lowest (1.52 kg/bird/day) for the 100%FFCS diet. Birds on the 100%FFCS also showed a 34% slower growth rate (average daily gain of 152.0 g/bird/day) compared to the other four diets (average growth rate of 230 g/bird/day) during the grower phase. The 0%FFCS (236.2 g/bird/day) and 50%FFCS (267.8 g/bird/day) diets resulted in a higher ADG. End weights during the grower phase for 0%FFCS, 25%FFCS, 50%FFCS and 75%FFCS (74.8, 72.2, 76.8, and 72.5 kg, respectively) did not differ significantly. The 100%FFCS resulted in a lower end weight (67.4 kg) for the growth phase, when compared to the 0%FFCS and 50%FFCS diets. For the overall trial period, the only differences were in ADG, with the 0%, 50% and 75%FFCS replacement diets showing the fastest growth. Fat pad weight was the only slaughter trait that revealed differences between diets, with 50%FFCS resulting in the heaviest fat pad weight. A maximum of 20.6% inclusion of FFCS should be used in diets in the grower phase, although in the other phases, FFCS could be included up to the maximum level evaluated (100% replacement of soybean oilcake meal) without detrimental effects on production parameters.