مجله علوم دامی ایران
سال پنجاه و چهارم شماره 4 (زمستان 1402)

In order to determine the effects of sodium acetate and conjugated linoleic acid (CLA) on dry matter consumed, feed digestibility, milk yield and milk fat profile, 33 Holstein cows several calving times during days 5-31 after calving in a completely randomized design with Three treatments and 11 replications were used. The experimental diets included 1- basic diet (control), 2- diet containing 300 gr of sodium acetate , 3- diet containing 100 gr of CLA. Daily dry matter intake and milk production, body weight and body condition score were measured at the beginning and end of the experiment. milk samples were taken at regular intervals to determine the amount of milk compounds. Also, on the last day, a sample was taken to determine the profile of fatty acids. Dry matter intake was not significant among dietary treatment (P>0.05). Milk production was increased by supplementing diets with sodium acetate (3.16 kg/d) and CLA (2.46 kg/d) compared to control treatment. CLA supplementing decreased milk fat content significantly and sodium acetate increased it. The yield and content of milk protein and lactose were not significantly different between the treatments. With the consumption of sodium acetate, the amount of milk fat and milk production increased, as probably the hypothesis that sodium acetate is lipogenic for adipose tissue was ignored and Acetate partition nutriunt toward milk fat production. CLA consumtion, negative energy balance did not change between as spared energy partition toward more milk yield. The use of CLA could be beneficial for the health of consumers by increasing the trans-10-cis-12 CLA isomer transfer to milk and reducing thrombogenic and atherogenic indicators.

The present study was conducted to evaluate the effect of supplementing egg yolk multi-antibodies against diarrhea pathogens on growth performance, hematological parameters, and feces microbial culture of Holstein suckling calves. 48 calves (male and female) were randomly assigned to three treatments and kept individually from 1 to 28 days of age. The treatments included the group fed with immunopro supplement (containing egg yolk multi-antibody and various probiotics, prebiotics, vitamins, and electrolytes) (IP), the positive control group containing all components of the treatment group without multi-antibody (C+) and the negative control group (C-). Feed intake was recorded every day, body weight and Skeletal growth parameters of calves was recorded every seven days, hematological parameters were measured on day 1 and 28, and feces microbial culture parameters were measured on day 28. The use of IgY supplements increased body weight, daily weight gain, dry matter intake, and feed efficiency (P < 0.05). Skeletal growth parameters (withers height, hip height, hip width, and Heart girth), hematological parameters, and feces microbial culture parameters were not affected by the experimental treatments. The use of IgY supplement decreased feces score, duration of diarrhea, and body temperature (P <0.05). The results suggested that the consumption of IgY against diarrhea pathogen's for up to 28 days promoted the immunity and health of Holstein's suckling calves.

This research was conducted in order to investigate the effect of peptides extracted from casein on performance, carcass characteristics and antioxidant properties of breast meat on 350 male broiler chicks in a completely randomized design with 7 treatments, 5 replications and 10 birds in each replicate. Treatments included: 1) basic diet without additives (control), 2) basic diet + Avilamycin antibiotic and basic diet + levels of 200 to 1000 mg/kg peptide. The results showed that the use of peptides period had not significant effect on feed intake in any periods of the experiment. Effect of peptides on body weight gain and feed conversion ratio in starter period was not significant. In grower, treatments containing 600, 800 and 1000 and in finisher and whole periods use of 800 and 1000 mg peptides increased body weight gain in compared to control treatment (P<0.05). Adding peptides also improved feed conversion ratio in grower, finisher and whole periods of the experiment. Use of 600, 800 and 1000 mg peptides decreased abdominal fat and increased heart percentage (P<0.05). Small intestine, duodenum, jejunum and ileum percentage in treatments supplemented with peptides significantly reduced (P<0.05). Use of peptides derived from casein improved the antioxidant properties of chicken breast meat (P<0.05). In conclusion, the results of the present study showed that use of  peptides derived from casein improved performance, decreased abdominal fat, small intestine percentages and increased breast meat stability in broiler chicks.

Sperm cryopreservation has become an indispensable tool in reproductive biology. However, maintaining fertility in frozen sperm is very important. The aim of this study is to investigate the effects of selenium nano-particles on the storage of dog semen at 4 ˚C during a period of 48 hours. In this study, 20 ejaculates were collected from 4 mix dogs and diluted in a Tris-based diluent. Then, they were divided into 4 parts in control and treated with 0.5, 1 and 1.5 µg selenium nano-particles groups. Sperm parameters including evaluation of total and progressive motility sperm, motility characteristics and viability of sperm were evaluated for 48 hours. The obtained results showed that in concentrations of 1 µg [progressive sperm (27.03±1.48), total motility (49.48±1.27) and viability (41.40±1.03)] and 0.5 µg [progressive sperm (30.76±1.67), total motility (53.18±1.54) and viability (43.15±1.58)] of selenium nanoparticles compared to the control group, but in the concentration of 1.5 µg was lower than the control group (p< 0.05). As a result, the present study showed that adding selenium nanoparticles in concentrations of 0.1 and 0.5 µg to dog semen can improve the parameters of dog semen after liquid storage, but in concentrations of 1.5 µg it causes toxic effects and overall agitation. And it reduces sperm viability.

In the poultry industry, the heat stress caused by high environmental temperature has a negative influence on broiler chicken performance and has become a major challenge. Transcriptome profile analysis of the data and identification of patterns of differential gene expression in related tissues can be involved in the discovery of molecular mechanisms resistant to heat stress. The main purpose of this study was to use transcriptome profiles of three tissues brain, liver, and leg muscle of two groups of the control and heat stress broiler chickens to identify candidate genes associated with heat stress. By the analysis of microarray data to express the gene differences, 657 significant genes (P<0.05) were extracted, which a total of 94 genes showed significant expression differences (FDR < 0.05, Fold change > ± 2). Then, by studying the ontology of the relevant genes resulting from data analysis and literature mining as well as the reconstructed protein-protein interaction network, hub genes including NSDHL, DHCR24, LSS, FDPS, PCK1, ACTA1, HSP90AA1, HSPA2, HSPB1, HSF1, CRYAB, APOB, and IL6 were identified. Annotation results of these genes indicated that they have a role in the main process of metabolic and signaling pathways related to the ion transport system, steroid, antibodies, cholesterol biosynthesis, lipid metabolism, immune system function, and various signaling pathways such as MAP kinase, RET, and ERK. Overall, the present study can provide new insights into evidence of the pathways activated by these genes to identify effective genes and a better understanding of biological processes related to heat stress.

The aim of this study was to evaluate the effect of limestone particle size and phytase enzyme supplementation on production performance, egg quality traits, and coefficient of apparent digestibility of calcium of commercial laying hens. A total of 216 laying hens were randomly distributed in six treatments, and six replicates per each. The design consisted of a factorial arrangement of three particle sizes of limestone from the same source (fine (<0.5 mm), medium (0.5-2 mm) and coarse (2-4 mm)) and two phytase levels (0 and 300 (FTU)/kg) in a completely randomized design. Egg production and egg mass were not influenced by experimental diets. Phytase inclusion numerically increased egg weight in second (P=0.06) and whole trial period (20-26 wk, P=0.1). Fine and coarse particles of limestone increased shell thickness (P < 0.01), compared to medium particles, also phytase supplementation improved shell percent (P < 0.01). Fine and medium sizes of limestone resulted in a higher apparent digestibility coefficient of Ca compared to coarse size ((P < 0.0001),0.43, and 0.45 vs. 0.33). Diets containing medium limestone size showed lighter yolk color than those containing fine and coarse particles (P˂0.05). Medium size of limestone significantly increased digestibility of DM compared to fine and coarse particles. In conclusion, productive performance of laying hens did not respond to limestone particle size, however, fine and medium sizes of limestone through enhancing effect on Ca digestibility, is more suitable than coarse particles for practical applications in young layers.

Oxidative stress plays a key role in sperm structure and function, semen quality and fertility. In poultry industries lipid peroxidation increases under chronic heat stress, particularly when the temperature exceeds 27 °C. In this situation, some practices are taken. One of important action is using pharmacological plant because of the lowest side effects. There is an increasing interest for applying natural antioxidants compare to synthetic because of the safety and low toxicity problems. The pharmacological plant generally used among foods. The use of natural antioxidant decreases sperm disorders and increases fertility. The rosemary has biological antioxidant mechanisms and belonging to thorny pharmacological plant, which is widely distributed in Europe and South-Eastern Asia. It has used in traditional medicine for its therapeutic properties. The Rosemarinus officinalis L. an evergreen perennial aromatic shrub belonging to the family Labiatae, commonly called rosemary. The rosemary is commonly used as a spice and flavoring agent in food processing. The rosemary contains some antioxidant phenolic that have been shown to provide a defense against oxidative stress from oxidizing agents and free radicals. The antioxidant capacity of rosemary is mainly related to the presence of components like carnosol, rosmanol, isorosmanol, epirosmanol, carnosic and rosmarinic acids. The antioxidant capacity of sperm is low, but enzymatic and non-enzymatic antioxidants in the seminal plasma protect sperm by scavenging the reactive oxygen species (ROS).

The objective of this study was to investigate the effect of vitamin A injection on reproductive performance in repeat breeder cows. One hundred and sixty-two multiparous Holstein cows with at least three consecutive unsuccessful inseminations were randomly assigned to experimental treatments. Treatments included (1) control: twice intramuscular injection 10 ml placebo30 days apart: 0.9% sodium chloride (n=87) and (2) vitamin A:  twice intramuscular injection 10 ml retinol palmitate 30 days apart (n=75). Animals submitted to double-ovsynch protocol and received their experimental treatments on the tenth day of the protocol (the day of the second injection of GnRH). The injection of retinol palmitate significantly increased the number of ovarian follicles larger than 10 mm compared to the control (P <0.05). Plasma concentration of superoxide dismutase enzyme tended to increase (P = 0.09) and malondialdehyde concentration tended to decrease (P = 0.08) under the influence of vitamin A injection. The conception rate at first artificial insemination was 25.29% and 34.66% for control and vitamin A treatments respectively, this difference was not significant (P = 0.19). The odds ratio of conception in the first service for vitamin A treatment was 1.57 times higher than the control treatment but was not statistically significant (P = 0.19). In conclusion, vitamin A injection improved antioxidant function and ovarian function. The reproductive performance improved, although not statistically significant.