فصلنامه محیط زیست جانوری
سال پانزدهم شماره 3 (پاییز 1402)

There is limited information concerning the interaction between grain and protein sources in starter diets on rumen fermentation profile and calf performance. It was hypothesized that calves would respond differently to various grain sources when fed with starter diets containing different protein sources. The objective of current study was to investigate the interactions between grain sources (corn vs barley) and protein sources (soybean meal vs. canola meal) on rumen fermentation profiles and calves’ growth. In a 2 × 2 factorial experiment, 40 calves (5 female and 5 male) were randomly assigned to four treatments to receive starter diets consisting 1. ground corn and soybean meal, 2. ground corn and canola meal, 3. ground barley and soybean meal, and 4. ground barley and canola meal. Volatile fatty acids, blood metabolite and calves’ growth were assessed for 65 days. Corn grain had no significant effect when included by soybean meal and canola meal, but barley grain resulted in higher total volatile fatty acids when canola meal included instead of soybean meal. The lowest starter intake was found for calves received barley-canola meal and the highest was for those received corn-soybean meal. Calves fed with starter diets containing corn soybean meal had greater average daily gain compared with calves fed barley-canola meal. The results revealed that corn grain is better than barley and and soybean meal is better than canola meal for calves starter formulation. The best composition was corn-soybean meal and the worst one was barley-canola meal which had the poorest effect on calves’ growth.

In this research, the characteristics of the distance from the withers to the ground, the back to the ground, the head to the ground, and the tail to the ground in 100 thoroughbred horses in Golestan province, which were randomly selected, and the effect of the ZFAT gene polymorphism on diversity of these traits were evaluated. To prepare blood samples, 5 to 7 ml was taken from the jugular vein of horses. DNA extraction from blood samples was done through the optimized saline method. After extracting DNA and evaluating their quantitative and qualitative characteristics, two regions of exon 13, including a fragment of 476 bp and intron 9 of ZFAT gene with a length of 457 bp, were amplified by PCR. To determine the polymorphism of PCR products, PCR-RFLP and PCR-SSCP methods were used to study regions of the gene. After identification of the genotypes, statistical analysis was performed to check the relationship between the mentioned genotypes and biometric traits, and the statistical analysis was performed with the linear GLM procedure of SAS software. The results of the present study showed that the ZFAT gene was polymorph in the intronic region and based on the number and size of digestive fragments in this gene region, three genotypes CT, TT and CC were observed with frequencies of 0.81, 0.11 and 0.08 respectively. Also, the calculations showed that the frequencies of T and C alleles are 0.86 and 0.14, respectively. The results of vertical electrophoresis of SSCP products showed three different band patterns on polyacrylamide gel, which indicated the existence of polymorphism and genetic diversity in exon 13 of ZFAT gene in thoroughbred horses. In this research, it was found that the frequency of band patterns A, B and C was 0.53, 0.40 and 0.07 respectively in the studied animals. Despite the observation of polymorphism in the above two areas, no association was observed between the studied traits and the types of genotypes, and regardless of this issue, considering the reliable reports that show the significant role of this locus on the height traits of the horse, it is suggested in the future researches, along with other gene loci, association of this gene with economic traits, including body size should be studied.

One of the environmental factors that lead to the reduction of poultry production is heat stress. Quince leaves are an agricultural waste that is a good source of flavonoid compounds and antioxidants. The purpose of this research is to investigate the effect of adding quince leaf in the diet on feed intake, weight gain, feed conversion ratio and blood parameters in broilers under heat stress conditions. This research was conducted using 160 broilers of Ross 308 strain with four treatments in four replications and each replication including 10 birds for 42 days in a completely randomized design. Quince leaf powder was added to the rations at four levels of zero (control), 1.5, 3 and 4.5%. In order to establish heat stress, the temperature of the hall was increased to 33 °C for 8 hours in the middle of the. Every week, the feed intake was measured and the chickens were weighed. In the second week of rearing, a significant increase (P=0.006) in feed intake was observed linearly with the increase in the level of quince leaf added to the feed rations, so that the highest amount of intake was in the treatment containing 4.5% quince leaf. In the third week, the highest weight gain was observed in the treatment with 1.5% quince leaf. In the fourth and fifth weeks, feed intake and feed conversion ratio did not differ significantly between treatments. In the sixth week, feed intake showed a significant decrease linearly (P=0.024) with the increase in the level of quince leaf added to the feed rations, but the feed conversion ratio linearly showed a significant improvement (P=0.017). In the entire rearing period, no significant difference was observed in terms of feed intake, weight gain and feed conversion ratio, although with the increase in the amount of quince leaf added to the feed rations, a relative improvement was seen in the feed conversion ratio, so that this ratio of 2.68 in the control treatment decreased to 2.44 in the treatment with 4.5% leaves. The use of quince leaf in the diets of broiler chickens under heat stress, especially in the early stages of growth, can increase feed intake, weight gain and improve feed conversion ratio, although no significant difference in terms of performance was observed in the entire rearing period, but a relative improvement was observed in the feed conversion ratio.

Selenium, a vital element in the body, plays a crucial role in the functioning of enzymes related to antioxidant defense, fertility, and the immune system. This study seeks to explore how various selenium sources impact the semen quality of aging broilers under lipopolysaccharide stress (LPS). A 2×3 factorial experiment involved 96 Ross 308 strain roosters at 45 weeks of age, organized into four replications of three birds each. The experiment included three selenium sources: mineral selenium (sodium selenite), organic selenium, and nano-bio chelate of selenium, added to the diet. Semen was assessed before LPS injection and after the final LPS injection at the experiment's conclusion. Evaluation indicators comprised malondialdehyde (MDA) concentration in semen, total oxidative capacity, glutathione peroxidase activity in semen, and testosterone levels in blood plasma. Statistical analysis utilized SAS 9.4 through GLM or MIXED procedures.The total antioxidant capacity and glutathione peroxidase activity levels exhibited variations among the groups. Specifically, in the LPS-receiving group, the control group demonstrated significantly lower total antioxidant capacity compared to the Selmax and Bendacel groups that received PBS. Additionally, the control group exhibited lower glutathione peroxidase activity compared to the Selmax group that received PBS, although no differences were observed between this group and others. Moreover, the Selmax group that received PBS displayed the lowest amount of MDA, a significant difference from the control and sodium selenite groups that received LPS. Notably, the testosterone concentration in birds that received Bendacel and sodium selenite, and were challenged with PBS, was significantly higher than in birds that received LPS without any source of selenium. The study demonstrated that using organic selenium from Selmax and Bendacel sources has the potential to enhance the reproductive performance of aged roosters, mitigating the adverse effects of aging. Notably, the effective addition of 0.30 mg/kg of organic selenium emerged as a positive intervention in improving reproductive outcomes in the study's context.

The addition of various substances such as probiotics and prebiotics and synbiotics and herbs and their extracts as possible alternatives to antimicrobial growth stimulants have positive effects on the host.The aim of this experiment was to investigate the effect of different levels of barley extract and synbiotic on yield, carcass characteristics and blood parameters of Ross 308 broilers. The experiment was conducted in a completely randomized design with 5 treatments, 5 replications and 10 chickens in each experimental unit for a total of 250 one-day-old chickens. Experimental treatments including control (without additive), barley extract 0.1%, barley malt extract 0.2%, barley extract 0.3% and soluble synbiotic in water were tested on broilers for 42 days. Feed-intake, weight gain and feed conversion ratio were recorded in initial, growth, final pahse and throughout the experiment. In order to determine the characteristics of the carcass and measurement of blood parameters, at 42 days of age, two male chickens were selected from each experimental unit and slaughtered after weighing. The results showed that the addition of barley malt extract at the levels of 0.1, 0.2, 0.3% and synbiotic alone on feed intake, weight gain and feed conversion ratio of broilers compared to the control was not significant. Also, adding 0.3% barley malt extract to drinking water caused a significant increase in triglyceride and VLDL-c serum levels of broiler chickens compared to the control (p <0.05), but other levels of malt extract barley and synbiotic had no significant effect on other blood parameters of broilers compared to controls. The present study showed that different levels of malt extract and synbiotic alone could not significantly improve the performance index and carcass efficiency throughout the experiment compared to the control group.

Achieving the sustainable development of aquaculture requires the use of new techniques, in which different strategies have been used, and the use of plant extracts, phytochemicals, and plant secondary metabolites due to their cheapness, availability, few side effects, and effective compounds and diverse has increased. This study was conducted to evaluate the growth and survival indicators of goldfish (Carassius auratus) fed with different levels of pomegranate peel powder (Punica granatum). 300 pieces of goldfish (Carassius auratus), apparently healthy, had passed the winter period in the pool environment, based on a completely random design, 20 pieces of goldfish with an average weight of 17.39±1.71 grams were distributed in 12 tanks. Then, they were reared with the basic diet as a control diet and three experimental diets containing 1, 2, and 4% of pomegranate peel powder. The initial weight was not significantly different in any of the treatments (P<0.05), but the highest percentage of body weight increase, specific growth rate, final weight, and body weight increase observed in the 4% treatment, which showed a significant difference with the other treatments. P>0.05); The food conversion ratio decreased in the treatments compared to the control group, and the fourth treatment showed a significant difference from the control (P<0.05); Also, an increase and maintenance of 100% survival were observed in fish (P<0.05). According to the results of the use of herbal supplements such as pomegranate peel powder with antioxidant properties, by increasing the secretion of digestive enzymes, they lead to improved growth performance and increased nutrient absorption, and according to the findings, the amount of 4% pomegranate peel powder in the goldfish diet to improve growth performance and survival is recommended.

This study was done to assess the antimicrobial and anti-inflammatory effect of raw and irradiated bee venom. Bee venom samples were irradiated at doses of 0, 2, 4, 6 and 8 kGy using gamma irradiator. Antimicrobial characteristic of raw and irradiated venom was determined using well diffusion assay. 300 µl of sample was poured in well and diameter of the clear zone of inhibition of growth for the bacteria and fungi was measured. Anti-inflammatory effect of venom was assessed using injection of formalin 2.5% in paw of rats. 24 rats was assigned to 6 treatments and 4 replicates for measurement of IL-6 and IL-10 in blood of rats. Raw and irradiated venom were injected to rats at a dose of 1mg/kg BW and blood sample was taken after 2, 4 and 6h, then serum was separated. Spleen was removed and hold in liquid nitrogen until gene expression analysis of IL-6 and IL-10. Data were analyzed based on randomized complete block design using SAS software. Irradiation of bee venom had no negative effect on antimicrobial and anti-inflammatory characteristics (P>0.05). IL-6 and IL-10 gene expression in spleen samples in rats taken 6, 48 and 72h post injection down regulated for venom irradiated doses of 4, 6 and 8 kGy compared with the control and dose of 2 kGy (P<0.05). Also, IL-6 and IL-10 gene expression down regulated in spleen samples of rats taken after 72h as compared with those taken 6 and 48h (P<0.05). There were no differ among serum levels of IL-6 and IL-10 in raw venom and irradiated at doses of 2, 4 and 6 kGy (P>0.05), but serum level of IL-6 increased (P<0.05) in those received 8 kGy irradiated venom compared with the control and other treatments. Based on the results of this study, gamma irradiation at dose of 6 kGy could applicable for honey bee venom processing without negative effects on positive venom characteristics.