EXPERIMENTAL POISONING OF HORSES AND CATTLE WITH SWAINSONA CANESCENS VAR HORNIANA

Horses and cattle fed swainsona ( Swainsona canescens var horniana ) over a period of 8 to 10 weeks lost condition and became incoordinated and hypersensitive. Histotogical examination of tissues from affected animals revealed the characteristic changes of widespread cellular vacuolation and axonal spheroids in the CNS.
Cattle withdrawn from the toxic plant after being fed for varying periods up to 8 weeks returned to normal.
Serum α-mannosidase activity declined significantly in cattle during the test period, whereas in horses the activity rose. Serum alkaline phosphatase levels increased significantly in cattle but not in horses.
The similarity of the clinical signs of disease in horses was noted to those seen in Indigofera linnaei poisoning (Birdsville disease). Differential diagnosis can be made by botanical observations and by an increased frequency of vacuolated lymphocytes in the blood in swainsona poisoning.     

Hepatotoxicity to dogs of horse meat contaminated with indospicine

SUMMARY: An outbreak of liver disease which killed more than 30 dogs at Alice Springs was associated with feeding meat from horses, some of which had developed Indigofera linnaei poisoning (Birdsville horse disease). Affected livers were small, nodular and yellow. There was associated jaundice, ascites, elevation of alanine aminotransferase levels in serum, a tendency to bleed, and signs of hepatic encephalopathy. Histologically, livers showed periacinar necrosis, collapse and haemorrhage, with severe swelling, vacuolation and cholestasis in remaining hepatocytes. Indospicine, a toxic amino acid found in the genus Indigofera, was detected in samples of suspect horsemeat. Experimental feeding of horsemeat containing 16 mg indospicine/kg for 32 days produced periacinar necrosis and hepatocellular swelling in 2 dogs, although neither died nor showed clinical illness. In another experiment, intakes of as little as 0.13 mg indospicine/kg bodyweightlday for 70 days produced periacinar liver lesions, and indospicine concentrations in serum, muscle and liver rose during this period to 3.9, 7.9 and 17.5 mg/kg, respectively. It was concluded that meat from horses grazing l. linnael can be hepatotoxic for dogs, and that this toxicity may be related to its indospicine content.     

Indigofera spicata (creeping indigo) poisoning of three ponies

Three ponies continuously grazed a pasture containing an estimated 24% Indigofera spicata (wet weight basis) for 4–6 weeks in April and May 2004. They developed ataxia, paresis, depression, muscle fasciculations, dysphagia, ptyalism and halitosis. Two also developed corneal opacity. One pony recovered with supportive treatment, but the other two were euthanased and necropsied. Neuropathology was not present in either case, but both livers had periacinar and periportal lymphocytic infiltrations and hydropic degeneration of mid‐zonal hepatocytes, with mild to moderate periacinar necrosis also evident in one. The I. spicata contained 2.66 mg 3‐nitropropionic acid (3‐NPA)/g dry matter and 1.5 mg indospicine/g dry matter. Indospicine, but not 3‐NPA, was detected in serum from both of the euthanased ponies and indospicine was detected in heart, liver and muscle from the one pony in which this assay was performed. The clinical syndrome closely resembled ‘Birdsville horse disease’ caused by I. linnaei and was similar to that reported in horses poisoned by the closely related species I. hendecaphylla and to 3‐NPA poisoning of other animals, including humans. 3‐NPA is thought to cause this neurological syndrome. To our knowledge, this is the first authenticated report of I. spicata poisoning in grazing animals. We also report here the first published evidence that 3‐NPA and indospicine exist in naturalised I. spicata in Australia and of the formation of indospicine residues in tissues of animals grazing paddocks infested with I. spicata.     

Psyllium Lowers Blood Glucose and Insulin Concentrations in Horses

A total of 16 mature healthy horses (body weight: 515.3 ± 37 kg [mean ± SD]) were used in two experiments to determine (1) how psyllium affects postprandial blood glucose and insulin concentrations, and (2) how psyllium affects blood glucose and insulin concentrations after an intravenous glucose infusion. Psyllium was fed along with a grain and hay ration (given twice daily) for 60 days. Treatments were as follows: (1) 90 g psyllium/d, (2) 180 g psyllium/d, (3) 270 g psyllium/d, (4) an isocaloric, no supplemental psyllium control. Pre- and postprandial blood samples were collected on day 60 for experiment 1, and blood samples collected before and after intravenous glucose infusion were analyzed for experiment 2. In experiment 1, horses fed with psyllium for 60 days had lower (P < .01) mean postprandial blood glucose concentrations and there was a treatment × time effect for glucose (P < .001) and insulin (P = .03). Plasma glucose was lower at 90 minutes (P = .05) and 120 minutes (P < .001) after a meal in horses fed with psyllium as compared with an isocaloric control. Postprandial serum insulin concentrations were lower at 90 minutes (P = .002) and 300 minutes (P < .001) after a meal in horses fed with psyllium as compared with an isocaloric control. In experiment 2, peak glucose concentrations were lower (P = .01) in horses fed with psyllium for the previous 60 days compared with untreated horses and there was a treatment by time effect for glucose (P = .05). Peak blood glucose response was lower (P = .01) in horses fed with psyllium as compared with an isocaloric control after intravenous glucose infusion, whereas peak insulin concentrations and average insulin concentrations remained similar. Psyllium fed daily for 60 days alters postprandial glycemia and insulinemia in normal, nonobese, and unexercised horses.     

Utilisation of ambadi (hibiscus cannabinus) meal by growing chickens

1. Experiments were conducted to compare the utilisation of ambadi meal with that of peanut meal in WL chicks and broilers.

2. Ambadi meal, either expeller‐processed (135.5 g and 271 g/kg) or solvent‐extracted (130.5 g and 261 g/kg), was incorporated at the expense of the peanut meal protein used in the reference diet (180 g/ kg) into diets which were fed to WL pullets (experiment 1) from 1 to 56 d of age. The weight gains and food efficiencies of the chicks fed on the ambadi meal and reference diets were similar.

3. With broilers (experiment 2) the weight gains were also similar, at all dietary concentrations of ambadi meal (89 to 356 g/kg), to those on the reference diet (235 g/kg peanut meal) from 14 to 35 d of age. However, food intake was higher on the ambadi meal diets and this resulted in significantly poorer food efficiency when compared to the reference diet.

4. High food intake and consequently low food efficiency was still evident in birds given ambadi meal diets even when ambadi meal replaced peanut meal on a digestible protein basis (experiment 4) or when ambadi meal (expeller or solvent‐extracted) was subjected to physical treatments such as soaking, autoclaving and pelleting (experiment 5).

5. The transit time of food through the gastro‐intestinal tract of broilers was faster when the diet contained ambadi meal than peanut meal. The higher food intake seen in broilers given diets containing ambadi meal could be the consequence of the fast rate of food passage.

6. Ambadi meal in diets for broilers resulted in significant increase (P<0.05) in the lengths of jejunum plus ileum and caecum. Fibre from the ambadi meal might have influenced the changes in the dimensions of gastro‐intestinal tract as well as in the transit time of food.     

Effects of a commercial dose of L-tryptophan on plasma tryptophan concentrations and behaviour in horses

Reasons for performing the study: L‐tryptophan is a common ingredient in equine calmative products, but its effectiveness has not been demonstrated in horses. Hypothesis: To determine whether a commercial dose of L‐tryptophan increases plasma tryptophan and alters behaviour in horses fed a roughage or concentrate meal. Methods: L‐tryptophan (6.3 g) or placebo (water) was administered per os in a cross‐over design, to 12 Thoroughbred horses (503 ± 12.1 kg bwt), just before a meal of lucerne hay or oats. Plasma tryptophan was measured by gas chromatography. Horse behaviour was observed in an empty enclosure, then in the presence of an unfamiliar person and a novel object. Results: Total plasma tryptophan increased 3‐fold in both studies, peaking 1.5‐2 h after dosing. After the peak, tryptophan remained high for several hours if the horses had been fed hay, but fell sharply if fed oats, consistent with the glycaemic responses to these meals. However, the ratio of tryptophan to 4 large neutral amino acids (phenylalanine, tyrosine, leucine and isoleucine) increased in the tryptophan‐treated horses to a similar extent and for a similar duration, with both diets. The presence of a stranger or novel object increased heart rate (P<0.05), but caused no behavioural effects that were altered by tryptophan, regardless of the diet. Conclusions: Plasma tryptophan increases when tryptophan is administered at a dose used in some commercial products, but this is not reflected by marked behavioural changes in the horse. Potential relevance: Further work is required to refine behavioural tests and identify an effective dose of L‐tryptophan in the horse.     

Comparison of the effects of fructose and glucose supplementation on metabolic responses in resting and exercising horses

The aim of this study was to compare the effects of two different carbohydrate sources (fructose and glucose) on the metabolic responses in resting and exercising horses. The following regimes were fed in randomized order to five trained horses at rest and immediately before or during exercise. The resting regime comprised 0.6 kg grass meal pellets (control) or 0.6 kg grass meal pellets supplemented with either 50% glucose or 50% fructose. The exercise regime comprised 0.3 kg grass meal (control) or 0.6 kg grass meal pellets supplemented with either 50% glucose or 50% fructose fed immediately before or during simulated endurance exercise on a treadmill (30 km, total running time 120 min; 15 min rest after 60 min running time). Blood samples were collected for the analysis of glucose, insulin, free fatty acids (FFA) and lactate. In resting horses, glucose supplementation resulted in a significantly higher glycaemic and insulinaemic response than the control or fructose feedings (treatment P < 0.05). Plasma glucose levels were significantly higher after glucose supplementation given before or during exercise. Similar plasma glucose concentrations were observed after fructose was fed before exercise, whereas fructose supplementation during exercise resulted in a lower glycaemic response than glucose feeding (P < 0.05). Plasma insulin, FFA and lactate levels showed exercise-related changes (time P < 0.05), but treatment did not effect these results. Plasma glucose concentrations were elevated during the simulated endurance exercise after glucose feeding, and no counter-regulation by insulin occurred. The higher glycaemic response might be beneficial as exogenous glucose can be used as an energetic substrate during prolonged exercise. Fructose exhibited no clear advantages in comparison with glucose as a carbohydrate source for exercising horses.     

Pathological Lesions in Lambs Fed Raw or Processed Cottonseed Meal

Thirty male lambs of 3–4 months of age, were assigned equally to five dietary treatments in a completely randomized design and fed isonitrogenous and isocaloric concentrate mixtures containing 30% de-oiled peanut meal (DPNM) or 40% cottonseed meal, which was raw, cooked for 45 min or treated with either 1% calcium hydroxide or iron (1:3, free gossypol: Fe). The mixtures containing raw or variously processed CSM replaced about 50% of the nitrogen of the reference concentrate mixture. These concentrate mixtures were fed to meet 80% of the animals' crude protein requirements along with ad libitum feeding of maize (Zea mays) hay for 180 days. The free gossypol content of the raw cottonseed meal (0.27%) was reduced to 0.16%, 0.20% and 0.21% by the cooking, Ca(OH)₂ and iron treatments, respectively. At the end of the experiment, the tissues of various organs were fixed in 10% formol saline, embedded in paraffin and sectioned at 4–5 m thickness, and duplicate sections were stained with either haematoxylin and eosin or Perl's Prussian blue. The lambs fed diets incorporating raw, cooked, Ca(OH)₂- or iron-treated cottonseed meal consumed respectively 302, 215, 250 and 222 mg free gossypol/day. No morbidity, mortality or gross lesions were observed in any organs and the histopathological lesions due to cottonseed meal were limited to the testes and epididymis. Spermatogonial cells were absent in the majority of the seminiferous tubules of testes from lambs fed raw cottonseed meal. Most seminiferous tubules were collapsed, with a reduced wall thickness, owing to there being fewer germ cell layers and vacuolation of the basal cells. The epithelium of the epididymal ductules was degenerated, desquamated to a variable degree with hyperplastic changes, and they were devoid of spermatozoa. Most lambs fed any of the processed cottonseed meals did not show any of these lesions, and such lesions as occurred in affected lambs in these groups were relatively mild. Iron pigments were deposited around the portal areas of the liver, the tip of intestinal villi and the spleen of lambs fed the iron-treated cottonseed meal diet. Cooking or treatment with 1% Ca(OH)₂ effectively minimized the toxic effects of free gossypol.     

Growth of yearling fillies fed alfalfa or soybean meal

Sixteen Quarter Horse yearling fillies were used in a 112-day randomized block experiment to determine the comparative efficacy of alfalfa hay protein to support growth in young horses. The yearlings were divided into two groups of eight and paired according to weight and age, with one yearling from each pair randomly allotted to each diet. Group 1 was fed a diet of coastal Bermuda grass hay and concentrate. The corn-based concentrate was supplemented with soybean meal such that the total diet for group 1 contained approximately 13% CP. Group 2 was fed a diet that also contained approximately 13% CP and consisted of alfalfa hay and a similar concentrate without soybean meal. Yearlings were fed the diets in a 60:40 grain-to-hay ratio, and intakes between members of each pair were equalized. The calculated digestible energy density in both final diets was approximately 2.85 mcal/kg, and the protein:calorie ratio for both diets was approximately 45 gm/Mcal. Body weight, body length, heart girth, wither and hip heights, as well as forearm, gaskin and cannon bone circumferences were measured every 28 days. Rump fat thickness was measured ultrasonically every 28 days. Physical measures of growth were similar for horses eating each diet (P>0.05). Also, blood urea nitrogen was similar for horses eating each diet (P>0.05) and was not reflective of differences in nitrogen metabolism. The fillies fed the SBM-supplemented diet retained more nitrogen more efficiently than did fillies fed the alfalfa diet (P<0.05), and the SBM-fed fillies had higher concentrations of osteocalcin on days 14, 28, 42, and 112. It can be concluded that SBM and alfalfa proteins were equally effective in providing growth to young horses; however, the biological value of absorbed nitrogen appeared to be higher in the fillies fed the SBM-supplemented diet. also, differences in serum osteocalcin concentrations indicate that the SBM-fed fillies were experiencing a greater amount of osteoblastic activity than the alfalfa fed fillies.     

Effect of a prebiotic on performance of partridge

An experiment was conducted to investigate the effect of a prebiotic on performance of partridge. The experiment was carried out with a total of eighty‐day‐old male Chukar partridge (Alectoris chukar chukar) chicks in a completely randomized design. The dietary treatments consisted of a control and an experimental treatment, and each treatment was replicated four times with 10 chicks per replicate. The experimental period lasted 16 weeks with a starter period (0–8 weeks) and a grower period (9–16 weeks). The control group was fed the basal diet, while the experimental group was fed the basal diet supplemented with 0.18% prebiotic Aspergillus meal in each period. Performance parameters included body weight gain, cumulative feed consumption and cumulative FCR and were recorded at biweekly intervals. Carcass characteristics and blood parameters were measured at the end of the experiment (week 16). Although the results showed that prebiotic had no significant effect on body weight gain and cumulative feed conversion ratio; however, the supplementation of Aspergillus meal significantly (p < 0.05) decreased cumulative feed consumption. Also prebiotic significantly increased percentages of breast and gastrointestinal tract, decreased percentage of back‐neck, decreased blood triglyceride and total cholesterol content and increased blood calcium content. From this study, it was concluded that dietary supplementation of 0.18% Aspergillus meal might offer beneficial effects on partridge feed consumption, carcass quality and blood cholesterol.     

Effect of dietary nucleotide supplementation on performance and development of the gastrointestinal tract of broilers

1. Two experiments were conducted to determine the effects of dietary nucleotide supplementation on broiler performance, and physical and morphological development of the gastrointestinal tract.

2. Experiment 1: A total of 180 one-d-old male chicks were placed in battery brooders in 3?×?6 replicate pens containing 10 chicks each. Chicks were randomly assigned to one of the three dietary treatments; a maize-soyabean meal based diet supplemented with 0, 0·25, and 0·50% Torula yeast RNA (as a source of nucleotides) from 0 to 16?d of age.

3. Experiment 2: A total of 1344 one-d-old male chicks were placed in floor pens and reared on recycled wood shavings (two flocks) under a high stocking density (0·068?m²/bird). Chicks were randomly assigned to one of the 4 dietary treatments (0, 0·25% Torula yeast RNA, 2% and 6% Nupro®) for the starter period (0 to 14?d of age) with 6 replicate pens containing 56 chicks each. All the birds were fed on the same common grower diet with no supplementation of nucleotides from 15 to 32?d of age.

4. Experiment 1: Supplementing the diets with up to 0·50% Torula yeast RNA did not affect broiler performance, or relative intestinal tract weight and length of broilers at any periods measured.

5. Experiment 2: From 0 to 14?d of age, broilers fed on the diets supplemented with 0·25% Torula yeast RNA and 2 and 6% Nupro® were significantly heavier and had improved feed conversion (feed:gain) ratios as compared with the birds fed on the control diet. Supplementing the starter diet only with 2% Nupro® supplementation significantly improved body weight (BW) gain as compared with the control diet over the entire experiment (0 to 32?d of age). Broilers fed on the diets supplemented with 2 and 6% Nupro® from 0 to 14?d of age had better feed conversion (feed:gain) ratios over the entire experiment (0 to 32?d of age) as compared with the birds fed on the control diet, even though the birds were only fed on the diets supplemented with Nupro® from 0 to 14?d of age. The broilers fed on the diets supplemented with 0·25% Torula yeast RNA and 2% Nupro® had higher villus height and an improved villus height-to-crypt depth ratio as compared with birds fed on the control or 6% Nupro® diet at 14?d of age.

6. It is generally assumed that nucleotides are not an essential nutrient; thus there is no need to supplement the diets of broilers reared under normal conditions. However, dietary nucleotide supplementation may be important to maintain maximum growth performance when birds are exposed to stress conditions, such as high stocking density combined with dirty litter.     

Effect of feeding increasing quantities of starch on glycaemic and insulinaemic responses in healthy horses

The aim of this study was to investigate the effect of increasing the intake of starch on the glycaemic and insulinaemic responses of horses. A cross-over study design was used in which four horses were fed increasing amounts of a compound feed (0.5–3.5 kg) to provide 0.3, 0.6, 0.8, 1.1, 1.4 and 2 g starch/kg bodyweight (BW)/meal. The glycaemic response increased with starch intake (P < 0.05), while feeding <1.1 g starch/kg BW resulted in a lowered response, compared to when 1.1–2 g starch/kg BW was fed (P < 0.01). The results suggested that insulin responses may be more appropriate to define the effect of feeding different starch levels than glycaemic responses. A starch intake of <1.1 g/kg BW/meal produced only moderate glucose and insulin responses, even though highly processed cereals were used. It is therefore recommended that a starch intake of <1.1 g/kg BW/meal or a meal size of 0.3 kg/100 kg BW (starch content of 30–40%) is used for horses.     

Feeding of Ferrets with the Raw Meat and Liver of Chickens Chronically Poisoned with Toxic Groundnut Meal

Chickens were fed a ration containing 30 per cent of toxic groundnut meal for up to six weeks. The concentration of aflatoxin (toxic metabolites of Aspergillus flavus) in the above ration was 3.06 p.p.m. At the end of 2nd, 4th or 6th week the birds were killed. The meat was removed from the bones and put through a meat grinder. The livers of three groups were pooled together. Three control groups of birds kept on commercial pellets were treated similarly.

Female ferrets, two years of age, were used in the present study. They were divided into four groups. The first three groups were given for one month meat from chickens fed the toxic ration for 2, 4, and 6 weeks, respectively. Each of these three groups contained one control ferret that was fed with the meat of chickens fed a commercial ration for a similar period of time. One half of the 4th group was fed pooled liver from intoxicated birds and one half was fed liver from control birds.

No significant changes in the ferret tissues were observed as a consequence of feeding them with the meat or liver from the chickens chronically poisoned with toxic groundnut meal.

     

Effects of Feeding Management on the Equine Cecal Microbiota

The effects of meal size and frequency on equine cecal microbiota are not well documented. We hypothesized that changes in feeding management (including differing meal size and frequency) would alter the equine cecal microbiota. Cecally cannulated horses (n = 6) were utilized in a 3 × 3 Latin square where they received group pasture turnout daily and were stalled overnight in box stalls (3 × 4 m). Treatment diets consisted of Strategy^® concentrate and were as follows: A = one meal, 2.72 kg, 6 AM; B = two meals, 1.36 kg/meal, 6 AM and 4 PM; and C = three meals, 0.91 kg/meal, 6 AM, 12 PM, and 4 PM. Treatment periods consisted of 8 days of acclimation followed by 3 days of collection. All horses received ad libitum access to water, a white salt block, and 3 kg of mixed alfalfa/grass hay offered overnight. Cecal samples were sequenced using 16S rRNA gene-based Illumina technology. Data were analyzed using QIIME 1.8.0 and Proc MIXED of SAS. Weighted principal coordinates analysis values indicated that feeding management impacted cecal microbiota composition with horses fed one large meal having different microbial community than those fed three smaller meals throughout the day (P = .028). Furthermore, treatment affected (P < .05) Prevotella, YRC22, Lactobacillus, Streptococcus, Coprococcus, and Phascolarctobacterium. These data demonstrate that feeding a single large bolus meal affects both abundance and composition of the cecal microbiota. Further research is necessary to understand the metabolic and/or health implications related to changes the equine cecal microbiota.     

Growth performance,carcass traits and meat quality of yellow‐feathered broilers fed graded levels of alfalfa meal with or without wheat

The effects of 0, 40 and 80 g/kg alfalfa meal on growth performance, carcass traits and meat quality of Chinese yellow‐feathered broilers fed diets containing or lacking wheat (0 or 200 g/kg) as part of the energy source, were examined using random design with a 2 × 3 factorial arrangement of treatments. Dressing percentage and semi‐eviscerated proportion were lower, and meat color a* (redness) value was higher in birds fed diets containing wheat than diets lacking wheat (P < 0.05). Drip loss was reduced by the addition of alfalfa meal to diets containing or lacking wheat (P < 0.05). Average sensory score of breast meat was higher in chickens fed corn‐based diets than in those fed wheat (P < 0.05). Meat from those supplemented with 40 g/kg alfalfa meal had better taste than the other two levels (P < 0.05). The inclusion of wheat significantly reduced the activities of creatine kinase and calpain of breast muscle (P < 0.05). In conclusion, Chinese yellow‐feathered broilers fed diets containing wheat had better meat color and lower drip loss than those fed the diets without wheat, and adding 40 g/kg alfalfa meal generally improved meat quality and taste.     

Effect of polyethylene glycol 4000 supplementation on the performance of indigenous Pedi goats fed different levels of <Emphasis Type="Italic">Acacia nilotica</Emphasis> leaf meal and <Emphasis Type="Italic">ad libitum</Emphasis> Buffalo grass hay

In a first of two experiments, twenty yearling male Pedi goats weighing 21.3 ± 0.5 kg live weight were used in a 37-day study in a 2 (levels of PEG 4000) × 2 (levels of Acacia) Factorial arrangement in a Completely Randomised Design to determine the effect of the level of Acacia nilotica leaf meal supplementation plus 23 g polyethylene glycol 4000 on diet intake and digestibility, and growth rate of Pedi goats fed ad libitum Buffalo grass hay. Acacia nilotica leaf meal contained high amounts of total phenolics (2.04 % DM) and low amounts of condensed tannins; both extracted (0.37 % DM) and unextracted (1.83 % DM). Supplementation with PEG 4000 increased (P < 0.05) crude protein intake as the level of Acacia nilotica leaf meal increased from 80 to 120 g. Similarly, treatment with PEG 4000 improved (P < 0.05) DM, OM and CP digestibilities when compared to 80 g Acacia nilotica leaf meal. Supplementation with PEG 4000 resulted in an increase (P < 0.05) in blood urea concentrations. Polyethylene glycol 4000 has the potential to improve the feeding value of A. nilotica leaf meal and can, therefore, be used in the feeding systems for ruminant animals. The second experiment determined the effect of A. nilotica leaf meal supplementation on in vitro digestibility of the diets similar to the actual ratios of the first experiment. Level of A. nilotica leaf meal supplementation plus 23 g PEG 4000 supplementation improved (P < 0.05) in vitro DM, OM and CP digestibilities where 120 g A. nilotica leaf meal was supplemented. Similarly, 23 g PEG 4000 supplementation also improved (P < 0.05) in vitro CP digestibility where 80 g A. nilotica leaf meal was supplemented. In vivo DM and OM digestibilities were best predicted from in vitro DM and OM digestibilities while in vivo CP was explained by in vitro OM and CP digestibilities. It is, therefore, concluded that in vitro DM and OM digestibilities have good capacity to predict in vivo DM and OM digestibilities while OM and CP digestibilities have good capacity to predict in vivo CP digestibility.     

Effects of supplementation of high-dosing Trichoderma reesei phytase in the corn-wheat-soybean meal-based diets on growth performance,nutrient digestibility,carcass traits,faecal gas emission,and meat quality in growing-finishing pigs

We conduct this study to investigate the effects of corn-wheat-soybean meal (SBM)-based diet supplemented with high-dosing Trichoderma reesei phytase on the growth performance, nutrient digestibility, carcass traits, faecal gas emission and meat quality in growing-finishing pigs (29.71–110.58 kg live weight; 70-day-old to 166-day-old). A total of 56 crossbred pigs [(Landrace × Yorkshire) × Duroc] were used in 96-day experiment with a completely randomized block design. The growing period was from day 0 to 42, and the finishing period was from day 43 to 96. Pigs were randomly allocated to one of two treatments with seven replicate pens and four pigs (two barrows and two gilts) per pen and fed corn-wheat-SBM-based nutrient adequate basal diet or the basal diet supplemented with 1500 FTU/kg diet Trichoderma reesei phytase. One phytase unit (FTU) was defined as the amount of enzyme that catalyses the release of one micromole phosphate from phytate per minute at 37°C and pH 5.5. Dietary supplement with Trichoderma reesei phytase had increased body weight on day 96 and average daily gain in days 0–96. Moreover, high apparent total tract digestibility (ATTD) of phosphorus (P) was observed in pigs fed with Trichoderma reesei phytase. However, the carcass traits, faecal gas emission and meat quality of pigs were unaffected by Trichoderma reesei phytase supplementation. In conclusion, supplementation of high-dosing Trichoderma reesei phytase (1500 FTU/kg diet) in the corn-wheat-SBM-based nutrient adequate basal diet increased body weight and the ATTD of P, while no adverse effects were observed on the production characteristics.     

Influence of bone meal degelatinisation and calcium source and particle size on broiler performance,bone characteristics and digestive and plasma alkaline phosphatase activity

1. The current experiment was performed to elucidate the effects of degelatinised bone meal (DBM) in combination with different particle sizes of limestone or oyster shell on broiler performance, bone characteristics and digestive and plasma alkaline phosphatase (ALP) activity.

2. Treatments were applied as a 3 × 3 factorial arrangement with three sources of P (DCP, bone meal and DBM) and three particle sizes (50, 100 and 200 µm) of limestone. Chickens were given either DCP or DBM with oyster shell (523 µm), resulting in a total of 11 treatments with 5 replicates of 8 chicks.

3. Performance criteria were measured weekly. Tibia strength, ash, calcium (Ca) and phosphorus (P) content and plasma P and Ca concentration along with plasma and intestinal alkaline phosphatase (ALP) activity and P digestibility were measured on d 14 and 28.

4. Body weight and FCR were improved in chicks which were fed DBM or oyster shell in comparison to the DCP and limestone respectively (P ≤ 0.05). Performance was influenced (P ≤ 0.05) by particle size; with coarser particles BW and feed intake were increased (P ≤ 0.05). Tibia shear force and P content were reduced (P ≤ 0.001), whereas tibia shear energy, length, ash and Ca content were increased by substitution of DCP with DBM or bone meal (P ≤ 0.001; P ≤ 0.05). A significant difference was observed in the tibia length between the chicks fed oyster shell or limestone with different particles (P ≤ 0.05). Plasma P concentration was reduced in chicks were fed with DBM, bone meal and lower limestone particle size. Intestinal ALP activity was increased (P ≤ 0.001) in chicks which were fed DBM, bone meal, oyster shell or coarse particles of limestone. The P digestibility in chicks fed bone meal was lower than that of those fed DBM or DCP (P ≤ 0.01). Overall, gelatin removal from bone meal improved broiler bone characteristics through the P digestibility and intestinal ALP activity enhancement.     

Growth and development of yearling horses fed either alfalfa or coastal bermudagrass: Hay and a concentrate formulated for bermudagrass hay

Two experiments were conducted with yearling horses to determine whether the use of a concentrate designed to be fed with Coastal bermudagrass hay would cause growth differences or skeletal abnormalities when fed with western alfalfa hay. In experiment 1, 13 thoroughbred and quarterhorse yearlings, 332.8 ± 8.5 days, of age were assigned at random within breed and gender subgroups to 1 of 2 diets: (1) alfalfa hay plus a 12.7% CP concentrate and (2) coastal bermudagrass hay plus the same concentrate. The horses were housed in drylot paddocks in groups of 3 or 4 animals and group fed the hay at 1 kg/100 kg BW daily. The concentrates were fed individually to appetite for two 1.5-hour feeding periods daily for 112 days. Orts were weighed back daily. The animals were weighed, measured, and blood samples collected at the start of the experiment and at 28-day intervals for 112 days. Radiographs of the third metacarpal were made on day 0, 56, and 112 for estimation of bone mineral content. In experiment 2, 15 thoroughbred and quarterhorse yearlings, 345.6 ± 8.4 days of age, were used to repeat the experiment. The concentrate fed in this experiment contained 12.4% CP. In experiment 1, the hay protein content was less than anticipated, resulting in a protein intake below NRC¹ recommendations. In experiment 2, the hay protein was higher and more typical of NRC¹ values. In both experiments, feed intake of the 2 diets was not different (P > .10). Weight gain (P = .0136, P = .0330), heart girth gain (P = .0084, P= .0044), and hip height gain (P = .0165, P = .0137) were higher for the alfalfa fed yearlings for experiment 1 and experiment 2, respectively. Withers height gain (P = .0079) and body length gain (P = .0232) were also greater for the alfalfa fed yearlings on experiment 2. Bone mineral content and bone metabolism indicators were not influenced by diet (P > .10).