IRANIAN JOURNAL OF APPLIED ANIMAL SCIENCE
Year:2011 | Volume:1 | Issue:1|Papers Count:10

Mycotoxins are an increasingly discussed topic. Several scientific reports have been written which review the effects of these toxic substances on the health and productivity of animals. However, there is a lack of work regarding the incidence of mycotoxins in ensiled material and the consequences of this occurrence. In this review, practical and field information was converged with scientific data with the objective of clarifying the subject. Nevertheless, due to the complexity of this topic, a straight line was adopted, starting with a brief explanation about mycotoxins followed by some practical prevention methods used on the field and during the ensiling process and, very importantly some analyses’ results made to silage from various origins and the impact of these contaminated materials in the animals ingesting them. An overview about how to avoid the negative impact of these poisonous substances is given as, for example, on the field (crop rotation, use of resistant plants, use of fertilizers, biological and chemical control of fungi and adequate plant maturation); in the silo (compaction, sheeting, storage length) and a correct management of the open silo (speed of progression in the silo, discard of deficiently preserved silage, additional use of silage additives for stopping the undesirable fermentations).

Artificial neural networks (ANN) have shown to be a powerful tool for system modeling in a wide range of applications. The focus of this study is on neural network applications to data analysis in egg production. An ANN model with two hidden layers, trained with a back propagation algorithm, successfully learned the relationship between the input (age of hen) and output (egg production) variables. High R2 and T for ANN model revealed that ANN is an efficient method of predicting egg production for pullet and hen flocks. We also estimated ANN parameters of a number of eggs on four data sets of individual hens. By increasing the summary intervals to 2 wk, 4 wk and then to 6 wk, ANN power was increased for prediction of egg production. The results suggested that the ANN model could provide an effective means of recognizing the patterns in data and accurately predicting the egg production of laying hens based on investigating their age.

Four West African Dwarf (WAD) grower bucks averaging 6 kg in weight and aged between 5-6 months of age were used in a digestive trial to determine the intake and digestibility of raw or processed pigeon pea seed meal based diets. The diets designated RPBD, SPBD, TPBD and BPBD were formulated from cassava peel, palm kernel cake, brewers dry grain, bone meal and common salt to contain 15% of raw, boiled, soaked or toasted pigeon pea seed meal, respectively. The diets were allotted to the 4 animals in a 4×4 latin square design. Results showed that feed and dry matter intake (DMI) (g/d) were influenced (P<0.05) by dietary treatments. The values were highest for BPBD followed by RPBD, SPBD and TPBD in that order. The feed and DMI of BPBD differed (P<0.05) significantly from values obtained for TPBD but similar with those of other diets. Nitrogen intake (g/d) of goats fed BPBD (7.49), RPBD (7.16) and SPBD (6.36) were similar (P>0.05); however, there was a significant difference (P<0.05) in nitrogen intake between goats fed BPBD and TPBD (5.90). Fecal nitrogen (g/d) values were fairly comparable (P>0.05) but urinary nitrogen (g/d) values were affected (P<0.05) by treatments; the value was highest in goats fed RPBD (1.32) which differed (P<0.05) from goats fed TPBD (0.76), SPBD (0.41) and BPBD (0.39). Nitrogen balance and nitrogen absorbed were also influenced (P<0.05) by dietary treatments; the values for goats fed BPBD (6.09, 6.48) differed significantly from values obtained for those fed TPBD (3.72 and 4.48) but similar with values obtained for RPBD (3.92 and 5.24) and SPBD (4.45 and 4.86).

This study was carried out at Sakha Animal Production Research Station, during the period from Oct., 2009 to Sep., 2010. Forty Rahmani ewes were divided into three treatment groups: the 1st, 2nd and 3rd treatment groups were intramuscularly injected (Day 0) with 1 mL GnRH analogue followed by an intramuscular injection with 0.7 mL PGF2 a5 (G1), 6 (G2) or 7 (G3) days later. A second dose of 1 mL GnRH analogue was given on day 7 (G1), 8 (G2) or 9 (G3), and artificially insemination of treated doze was carried out 24 h later, while the 4th group represented the control ewes which were allowed for natural mating from 1st to the end of January, the breeding season. Results show that one out of 10 ewes (10%) exhibited estrous activity in G1 versus 30% (3 out of 10 ewes) in both G2 and G3. Ewes in G1 treatment group showed highest (P<0.05) lambing rate (60%), followed by G2 (50%) and the lowest in G3 (40%), while, lambing rate of the controls was 60%. Litter size and fecundity were significantly the highest (P<0.05) in G1 (1.67/litter and 100.2%), followed by G2 (1.40/litter and 70%) and the lowest in G3 (1.25/litter and 43%), respectively. P4 concentration was significantly (P<0.05) increased in all treatment groups as affected by the 1st GnRH injection, thereafter, it showed marked decrease in all treatment groups post-PGF2 a injection.Post-2nd GnRH injection, P4 level showed again a pronounced increase in all treatment groups. On day 21-24 post-mating, P4 level showed the highest values in all treatment groups. Based on the foregoing results, using GnRH-PGF2-GnRH (GnRH, 0 d; PGF2a 5 d later and GnRH 48 h later) protocol during breeding season can be used for synchronization of estrus and ovulation to reduce service and lambing interval of ewes in the large flocks.

For identification of individuals and parentage control performed by cattle breeders in the Czech Republic, a novel Finnish Bovine Genotypes™ Panel 3.1 was amplified by means of one multiplex polymerase chain reaction. Bovine Panel encompasses all the 12 STR loci recommended by the International Society for Animal Genetics (ISAG) for routine use in parentage testing and identification, including TGLA227, BM2113, TGLA53, ETH10, SPS115, TGLA126, TGLA122, INRA23, ETH3, ETH225, BM1824 and BM1818. In addition, the kit included the following six microsatellites which were among the list of loci recommended by the Food and Agriculture Organization of the United Nations (FAO) for genetic studies of domestic animals: SPS113, RM067, CSRM60, MGTG4B, CSSM66 and ILSTS006. Afterwards, the length of these microsatellite’s polymorphisms was examined by fragment analysis of the amplified products. The investigated population consisted of 125 animals of three bovine breeds (Fleckvieh, n=50; Charolais, n=50 and Beef Simmental, n=25). A total of 337 alleles were identified and all microsatellite DNA markers showed high polymorphism. The probabilities of paternity exclusion/one parental genotype unavailable/and parentage exclusion were 0.9942/0.9798/0.9999 (Fleckvieh), 0.9834/0.9744/0.9999 (Charolais), 0.9828/0.9682/0.9999 (Beef Simmental). Research data certified the possibility of using the Finnish panel of DNA microsatellites markers for the traceability purposes in the Czech cattle populations.

This experiment was designed to evaluate the effects of different levels of tomato pomace (DTP) with different multi enzymes on the performance and egg quality of laying hens at the first phase of production. In this experiment 432 hens were used in a completely randomized design in a factorial arrangement of 4×4, with four levels of tomato pomace (0, 4, 8 and 12%) and different enzymes (without enzyme, Natozyme, Rovabio and Kemin) with three replicates of 12 laying hens in each replication. These rations were fed for a 12-wk period by hens (Hy-Line W-36) beginning at 33 wk of age. The results showed that the inclusion of DTP significantly affected egg weight (g), egg production (%) and difference between means of treatments were significant (P<0.05). Egg mass (g), feed intake (g), feed conversion ratio (kg/kg) and egg quality traits (specific gravity, yolk Index, Eggshell thickness (mm) shell weight (g), Haugh unit) were not affected with DTP and different enzymes. There were no significant interactions between the DTP and enzyme supplementation on egg production and egg quality. There was a significant improvement in the egg yolk color in treatments containing DTP. The inclusion of DTP, resulted in a decrease of cholesterol in the serum (P<0.05).Moreover, the inclusion of DTP had no effect on yolk cholesterol. A suggested maximum inclusion level of 8% TP, based on these data can be used in commercial diets, but it is speculated that the incorporation of multi enzyme was not effective on improvement of DTP effects.

Overcrowding of broiler chicks due to lack of space induces harmful effects which act as predisposing factor in the reduction of production and performance in poultry. Supplementation of antistressor products can ameliorate adverse effect of various stressors in poultry. An experiment was designed by inducing overcrowding stress and its management by supplementation of polyherbal antistressor, adaptogenic and immunomodulator formulation Stresroak in broiler chicken. One hundred and fifty day old broiler chicks were randomly divided into five groups of 30 chicks each. Groups I, II and III served as control and were only offered with basal diet. Group I served as control with a normal space. The chicks in groups II and III (positive control) were provided with space 25% and 50% lesser than normal, respectively.The bird in therapeutic group IV and V were provided with 25% and 50% less space along with antistressor Stresroak@1g/1kg of feed, respectively. Growth and performance related parameters like feed consumption, body weight, feed conversion ratio (FCR) were evaluated in addition to haematological, serum biochemical and gross pathological studies. Polyherbal formulation not only improved growth and performance related parameters, but also normalized the haematological and serum biochemical parameters. Gross pathological lesions in vital organs also showed improvement in therapeutic group compared to control.It was concluded that Stresroak exhibits antistressor and adaptogenic activity to ameliorate the overcrowding stress in poultry.

Twenty eight lactating buffaloes were used in a completely randomized design with 2×2 factorial arrangement of four experimental diets including low protein-low energy (LP-LE), low protein-high energy (LP-HE), high protein-low energy (HP-LE) and high protein-high energy (HP-HE). Results showed that the HP-HE diet recorded the highest digestibility coefficients of CP, EE, NFE, nutritive values, TDN and DCP intake, while HP-LE diet had the highest CF digestibility (P<0.05). The HP-HE diet had the highest (P<0.05) actual milk and 7% FCM yield and the contents of protein, lactose, SNF and TS in milk, HP-LE diet had the highest fat content (P<0.05). The HP-HE diet showed the lowest amounts of DM and TDN per kg, 7% FCM, while LP-HE diet had the lowest amount of DCP per kg 7% FCM (P<0.05). The LP-HE diet recorded the lowest average daily feed cost, while HP-HE diet showed the lowest feed cost/kg 7% FCM and the highest total revenue and economic efficiency (P<0.05). Buffaloes fed HP-HE diet showed short periods from parturition to first estrus and first service, service period, days open, the lowest number of services per conception and the highest conception rate (P<0.05).

This experiment was conducted to determine the effect of using L-threonine and reducing dietary levels of crude protein (CP) on egg production criteria in layers. Three hundred of Hy-Line W36 laying hens were used in this experiment. This experiment consisted of three experimental treatments with five replications in each. Experimental treatments included 3 diets with different levels of CP which were 15, 16 and 17% with 0.1, 0.05 and 0.02% L-threonine supplementation, respectively. Experimental period lasted for 5 weeks. In this experiment quantitative factors such as egg mass, egg weight, egg production percentage, feed conversion ratio (FCR), body weight and feed intake were measured. Measured data were analyzed by completely randomized design (CRD). Results indicated that reducing dietary levels of CP to 15% and using L-threonine supplementation had no significant effect (P>0.05) on laying criteria. According to economic analysis, the treatment containing 15% CP and 0.1% L-threonine was the most beneficial treatment.

This study aimed to investigate the relationship between race horse breed and the frequency of limb injuries through the time of training and racing. The study population consisted of 4042 Thoroughbred and 2553 Arabian horses raced at Warsaw race Track, from 2000 to 2008. Among these horses, 94 Thoroughbreds and 32 Arabians had different limb injuries. Based on the achieved results, it is possible to conclude that limb injuries are significantly more common in Thoroughbred race horses than in Arabians. Male horses of both breeds were at significantly higher risk of limb injuries. It was also shown that front legs were injured more often than hind ones in both studied breeds.