IRANIAN JOURNAL OF APPLIED ANIMAL SCIENCE
Year:2012 | Volume:2 | Issue:1|Papers Count:15

Induced abortion may be desired during a normal or abnormal pregnancy. The methods of induced abortion dif-fer between species mainly because of different sources for progesterone production during pregnancy between species and within a species according to different stages of gestation. In cows and buffaloes, pregnancy can be effectively terminated from 5 to 150 days by administration of luteolytic doses of prostaglandin F2 alpha (PG). From 150 days onwards and till term bovine and bubaline pregnancies can be safely terminated by administration of a combination of PG and dexamethasone. During the last month of pregnancy in these two species, pregnancy can be successfully terminated by using either a PG or dexamethasone. In goats pregnancy can be terminated during the entire gestation by administration of luteolytic doses of prostaglandins. In sheep pregnancies up to 55 days can be terminated by administration of 100 μg cloprostenol or 10-12 mg of dinoprost. From day 55 onward the termination of sheep pregnancies requires the administration of single or multiple injections of dexamethasone. Early pregnancy (day 5-34) termination in the mare can be achieved by physical methods or ad-ministration of PG. The same treatment is effective in terminating pregnancies between days 35-120 but repeated injections are required and because the endometrial cups continue to exist for a couple of days after pregnancy termination, mares do not return to estrus for prolonged periods. The termination of equine pregnancy after 4 months is difficult till term. The results of administration of PG or corticosteroids is suboptimal and manual disruption of the fetus after dilation of the cervix with PGE2 creams is more reliable method of pregnancy termination.

This study was aimed to evaluate the effect of GnRH injection on semen ejaculate characteristics in Awassi rams collected in breeding and non-breeding seasons. The study was conducted in late summer to early au-tumn when breeding activity commences, and in winter during the non-breeding season. Twelve mature Awassi rams were used in this study. Animals were randomly allocated into two equal groups, the experi-mental group received 50 μg IM of GnRH weekly and the control group received 1 ml of saline. Libido was assessed and semen samples were collected from the Awassi rams 24 hours after IM administration. Scrotal circumference (SC) and testicular volume were measured weekly during the study period. Ejaculates were collected 24 hours after each GnRH/saline administration and assessed for volume, sperm concentration, mass and individual motility, live sperm and sperm abnormalities. Seminal plasma was assayed for the estimation of alanine amino transferase (ALT), aspartate amino transferase (AST), acid phosphatase (ACP), alkaline phosphatase (ALP) and lactic dehydrogenase (LDH). Results show that GnRH treatment improves semen volume, total ejaculated sperm and reaction time in both breeding and non-breeding seasons com-pared to control (P<0.05). However, GnRH treatment reduces the activity of LDH in both seasons. Other seminal traits show similar values for both seasons. In conclusion, GnRH treatment of Awassi rams im-proved libido, semen volume, sperm numbers, but not sperm viability.

A research study was carried out on the indirect selection efforts amongst small scale holders of West African Dwarf (WAD) goats based on coat pigmentation and wattle types in Ogbomoso, Nigeria using personal interviews and structured questionnaires given using simple random on-farm techniques. The questionnaires were focused on the ownership distribution, preferred pigmentation and wattle types, disease susceptibility, death status, kidding status and market sales regarding coat pigmentation and wattle types. The question-naires revealed that WAD goats with black pigmentation and two wattles had the highest ownership distribution, most preferred and better priced. It further revealed that black goats were highly diseased and died more, although this could be as a result of the preponderance of black goats in the study area. However, the respondents revealed that goats with two wattles were not easily susceptible to disease and lower deaths were often recorded. This showed that indirect selection of WAD goats based on coat pigmentation and wattle type is constantly going on amongst the small scale holders of WAD goats and this could be utilized for the breed genetic improvement.

This study was conducted to investigate the hair production and fleece characteristics of hair goats in Fars province. The material of the study included a total data of 84 hair goats, which were between kids and adult in male and female goats, respectively. The overall average for fleece weight, fiber length, staple lengths, washing yield, hair fiber diameter, of fiber diameter, breaking force, tenacity and elongation were 293.3±20.5 g, 5.5±0.3 cm, 8.0±0.5 cm, 73.8±0.5%, 81.0±1.9 um, 20.3±0.5%, 7.8±0.4 kg f, 9.5±0.4 gf/tex and 3.5±0.2%, respectively. It was found that the effect of sex on the hair traits except fleece weight was not statistically significant (P>0.01), whereas the difference between males and females on the fleece weight was significant. Fleece weights in males and females were 331.7±29.8 and 237.4±25.7 g, respectively. However, significant difference (P<0.01) was found in fleece weight, hair length, hair diameter and tenacity between two age groups except for washing yield, coefficient of variation CV of hair diameter and hair elongation. Adult goats had more fleece weight, fiber diameter, fiber lengths, staple length, breaking force and breaking tenacity than those of kids.

A trial was conducted to evaluate the performance of broiler birds which supplemented with a commercial inactivated probiotic. Four hundred and fifty day old broiler chickens were allocated into 3 treatments with 6 replicates each. Each replicate was placed on clean wood shavings in floor pens receiving feed and waterad libitum. In treatment 1, feed was supplemented with 500 g/ton of a heat-inactivated probiotic containing Lactobacillus spp, Bifidobacterium animalis, Pediococus acidilactici and Enterococcus faecium. In treatment 2, the feed was supplemented with 500 g/ton of the same probiotic without the heat-inactivating process (commercial product). In Treatment 3 the feed was supplemented with Zinc Bacitracin at 100 ppm. During the length of the experiment the birds received the following diets: pre-initial 1 to 7 days; initial 8 to 21 days; growth, 22 to 35 days; and finisher, 36 to 40 days. Data were analyzed following the same dietary periods. In addition, data was arranged in two periods of similar length; from 1 to 21 days and from 22 to 40 days. During the pre-initial phase, treatment 2 had higher weight gain compared to treatment 1. During the initial phase, treatments 1 and 2 had lower feed conversion compared to treatment 3. In the finisher, treatments 1 and 2 had higher body weight and lower feed conversion than treatment 3. In conclusion, regular and inactivated probiotics had similar performances which under the conditions of this trial were superior to the treatment containing 100 ppm of zinc bacitracin. These data suggest that not all growth promoting effects are mediated by bacterial metabolites or active colonization of the gastrointestinal tract.

This research was conducted to estimate the amount of microbial protein synthesis in Iranian buffaloes' rumen. Four male swamp buffaloes with average live body weight of 140±10 kg were used in this study. Four diets of 0 (control diet, 100% forage), 15, 30 and 45% concentrate in a 4 × 4 Latin Square were tested. The results indicated that by increasing the concentrate level in the diet of swamp buffaloes. the amount of purine derivatives (PD) excreted in urine. The amount of allantoin excreted in urine increased by increasing concentrate level form 0 to 45% (13.2 and 21.8 mmol/day; P<0.01). There was no significant difference between uric acid excretion from buffaloes fed with diets contained 15 and 30% or 30 and 45% concentrate (P>0.01). However, there was a significant difference between diets containing 45 and 15% concentrate level (P<0.01). The difference between control diet and other diets containing different levels of concentrates were significant (P<0.01). The total purine derivatives excretion and microbial nitrogen synthesis in rumen increased from 14.5 in control diet to 18.11, 21.58 and 24.55 mmol/day and from 38.76 in control diet to 60.44, 81.48 and 99.43 g/day in buffalos fed diets containing 15, 30 and 45% concentrate, respectively. The results of this experiment indicated that increasing the concentrate level in diet of swamp buffaloes increases the amount of microbial protein synthesized in rumen.

The aim of the experiment was to determine the effect of different dry matter content and addition of silage inoculant on the ruminal protein degradability. Alfalfa herbage was collected from two cuts and the fresh matter was sampled two times during each cut (with different dry matter content). During the preparation of experimental micro-silages, the chopped forage was treated with a microbial inoculant or it was left un-treated (control). Thein sacco method was used for the measurement of ruminal protein degradability. The different dry matter content significantly (P<0.05) affected the rate of ruminal protein degradation in alfalfa silages. The average values of ruminal protein degradability of alfalfa silages were at lower dry matter con-tenth of 70.72±1.243%, at higher dry matter content 73.69±0.554% in the first cut. The ruminal protein de-gradability was significantly (P<0.01) different in the second cut. The alfalfa silages had average value of ruminal protein degradability at lower dry matter content of 69.19±1.184%, at higher dry matter content of 72.74±0.637%. The applied ensiling additive had no statistically significant influence on the ruminal pro-tein degradability in alfalfa silages. In first cut, it was measured in control silages as 72.08±1.620% and in inoculated silages as 72.33±1.901%. In second cut, the average values of ruminal protein degradability of control silages were 71.56±1.833% and of inoculated silages as 70.37±2.014%. The using of bacterial in-oculant had no significant effect of ruminal protein degradability, but improved the fermentation process quality.

The aim of this study was to determine the effect of yeast culture (Saccharomyces cerevisiae SC 47) addition in the diet of dairy cows on their rumen fermentation and milk production. Animals received a diet TMR based on good maize silage with a higher dry matter content (14 kg), 14 kg of lucerne-grass haylage, 5 kg of crushed ears of maize, 5 kg of beet pulp silage, 3 kg of crimped wheat, 2 kg of meadow hay, and 7.0 kg feed mixture. The yeast culture (5 g/day) was added to the mixture. The supplementation of yeast culture showed a positive effect on ruminal volatile fatty acids (VFA) production by the experimental group of Holstein cows in comparison with the control, higher production (P<0.05) on sampling days 30 and 60 (114±25.44 vs.125±26.49, and 146±32.47 vs.149±36.64, respectively). The average concentration of ammonia was higher by cows in the control group, and the difference vs. the treated group was significant. The difference in the number of protozoa of cows in the control and experimental groups was significantly (P<0.01) different (353±6.97 vs.386±3.91 ths/1 mL of rumen fluid). Average daily fat corrected milk (FCM) milk production was higher in the experimental group (38±3.33 vs.33±1.64).

The main objective of this study was to evaluate the effect of dietary inclusion of wheat or corn as the main source of starch in prepartum diets on colostrum composition, colostrum IgG1 and IgG2 concentrations, serum IgG1 and IgG2 concentrations of calves and efficiency of IgG1, IgG2 and total Ig absorption. For this purpose, thirty primiparous and twenty multiparous Holstein cows were used in a randomized complete blocks design. Cows were blocked by parity and expected calving dates and assigned to treatments at 27±2.5 d before calving. The dietary treatments contained corn or wheat grain as the main sources of starch. Blood samples of calves were drawn before the first colostrum feeding (0 h) at the birth and 24 h of life. The results indicated that prepartum diets had no effect on daily dry matter intake of cows. Lactose, fat and IgG2 concentrations in colostrum did not respond to dietary treatment, but protein, total solids, IgG1 and total IgG concentrations in colostrum were significantly higher for cows fed the wheat containing diet. At 24 h of age, serum IgG2 concentrations of calves were similar between the two treatments, while serum IgG1 and total IgG concentrations were significantly higher for calves fed colostrum from cows fed wheat containing diet. Prepartum starch source did not affect apparent efficiencies of IgG1, IgG2 and total IgG absorption. Briefly, the results indicated that feeding cows with the wheat containing diet in prepartum period increased colostrum quality and serum IgG1 concentrations in calves which in turn might have a posi-tive effect on health, survival and growth of newborn calves.

Quantitative traits locus for milk production traits has been described on centromeric end of bovine chro-mosome 14. Reports name the acyl coA: diacylglycerol acyltransferase (DGAT1) gene as a potential candi-date gene with dinucleotide substitution (AA to GC) in exon VIII which causes the change of lysine to alanine in amino acid (K232A).The aim of the present study was to estimate the frequency of DGAT1 K232A polymorphism in Iranian Holstein bulls as a potential quantitative trait locus (QTL) for marker as-sisted selection. Sample of 103 Holstein bulls from the Animal Breeding Center of Iran were genotyped for DGAT1 polymorphism (A and K allele). The PCR-RFLP technique was used to study the DGAT1 gene polymorphism. Frequency of KK, KA and AA genotypes were 0.59, 0.41 and zero respectively. The allele frequencies of the DGAT1 gene were 0.7961 and 0.2039 for K and A allele, respectively. The K allele was sequenced and registered in NCBI gene bank with EU075528 accession number.

This study was focused on the effect of wattle trait on body sizes and scrotal dimensions of traditionally reared WAD bucks in the derived savannah environment. Data were collected from 153 bucks ranging from 4 months to 2 years of age and this included, scrotal length, scrotal circumference, body weight, height at withers, body length and chest girth. Parameters for wattle traits included, wattle incidence (presence or absence), wattle shape (oval or cylindrical) and wattle position (under or beside neck). Data obtained were adjusted for age effect and subjected to Analysis of variance. There were significant effects (P<0.05) of wattle incidence, wattle shape and wattle location on body weight, body length, chest girth and scrotal length of WAD bucks. In addition, height at wither was only affected (P<0.05) by wattle shape. Cylindrically shaped wattled bucks whose wattles were located under the neck had more of body weight, body length, chest girth and scrotal length. Meanwhile, the height of goats whose wattles were cylindrical were more than those with oval shaped. Therefore, selection based on wattle traits can be employed as an indirect and affordable means of determining higher body sizes and fertility in WAD bucks.

This experiment was conducted to determine the chemical composition and gross energy of poultry by product meal (PBPM) and the effects of different levels of inclusion of poultry by product meal on broiler chicken performance, serum uric acid and carcass characteristics. Three samples of PBPM produced in Ardabil province located in northwest of Iran, were provided during one month sampling period from ren-dering units of industrial poultry slaughter-houses. About 210 U of industrial poultry slaughter-houses are located in Iran. The proximate analysis showed that the average dry matter (DM), crude protein (CP), ether extract (EE), Ash, calcium (Ca), phosphorus (P), total volatile nitrogen (TVN) and gross energy (GE) of the PBPM samples were 92.00%, 69.63%, 16.53%, 7.86%, 1.30%, 0.56%, 209 mg/100g and 4096.6 kcal/kg respectively. In this experiment 120 eleven days old Ross 308 male broiler chicks were used for feed evaluation of poultry by product meal in four levels of 0 (control), 30, 60 and 90 g/kg in whole diet for the periods of grower (11-32 d) and finisher (33-46 d) period in completely randomized design with 4 treat-ments and 3 replicates. The results showed that feed intake in all stages, body weight gain in finisher phase and overall period, mortality percentage and live weight at 46 d were similar between diets. While body weight gain in grower phase, feed conversion ratio in grower, finisher phase and overall period (11-46 d) of experiment and live weight at 32 d were statistically different (P<0.05). Therefore under the conditions of this study, use of 60 g/kg of poultry by product meal in diet might be more useful and practical in broiler diets.

The effects of chromium methionine supplementation on performance and serum metabolites were evaluated in broiler chickens. Two experiments were conducted at 22oC, thermoneutral, (TN) and 33±2 oC, heat stressed (HS) conditions. Two hundred and eighty eight male broiler chicks (Ross 308) were allocated to four treatments in a completely randomized design. Treatments with 0 (control), 200, 400 or 800 ppb of chromium methionine for 42-d experimental period carried out. Serum metabolites and performance were determined. Supplementing the diet of TN and HS conditions broilers with chromium methionine improved feed intake (FI) and body weight (BW) (P<0.05), but Feed conversion ratio (FCR) of broilers was not affected by different levels of supplemental chromium. Chromium methionine increased serum HDL con-tents, but decreased glucose, (GLU), cholesterol (CHL), triacylglycerol (TG) and LDL concentrations (P<0.05) in both TN and HS temperature. The results of these experiments indicated that supplementation of chromium methionine in the ration improved performance and influenced serum metabolites on thermoneutral and heat-stressed broiler.

This study aimed to decrease the cholesterol content of egg yolk of laying hens through inclusion of barley malt rootlets in the diets. Forty-two, 54-week-old, Lohman laying hens were fed for a 12 weeks laying period on 3 iso-caloric and iso-nitrogenous diets contained 0 (control), 25.5 or 51.1g barley malt rootlets/kg. Inclusion of barley malt rootlets at 25.5 or 51.1g/kg diet significantly decreased (P<0.001) concentrations of plasma cholesterol (by 54.9 and 33.3%, respectively) and triglycerides (by 26.4% and 27.3, respectively) compared with the control. Feeding barley malt rootlets at 25.5 g/kg diet tended to decrease (P>0.05) con-centrations of total lipids, triglycerides, cholesterol, low-density lipoproteins and phospholipids in egg yolk by 4.7, 5.7, 5.2, 3.9 and 5.3% respectively, while its inclusion at 51.1 g/kg diet significantly (P<0.05) de-creased the same respective parameters by 10.4, 10.4, 10.4, 10.6 and 11.22% respectively, compared with the control. It could be concluded that inclusion of barley malt rootlets in laying hen diets at 25.5 g/kg diet tended to decrease cholesterol and low-density lipoproteins in egg yolk (by 5.2 and 3.9%, respectively, while its inclusion at 51.1 g/kg diet decreased cholesterol and triglycerides concentrations in blood plasma and also decreased cholesterol and low-density lipoproteins in egg yolk (by 10.6 and 10.4%, respectively).

The present study was carried out to investigate the effect of different seasons on length and duration of estrus as well as to observe the behavioral changes and physiological peculiarities during estrus period. Three climatic seasons and age groups were considered: summer (March-June), rainy (July-October) and winter (November-February); A (6-9 month), B (9-12 month) and C (>12 month). Estrus behavior was monitored twice a day, using a teaser buck. The estrus were quantified within each season and classified as short (<17 days), normal (17-25 days) and long (>25 days). In case of seasonal effect, the length of estrous cycle did not differ significantly (P>0.05). The higher length of estrous cycle was found in summer (23.50±1.57 days) followed by winter (21.33±1.01 days) and rainy season (20.79±0.61 days), respectively. On the other hand, duration of estrus showed significant (P≤0.05) differences among the three different seasons. The longer duration was observed in winter (44.00±1.95 hours) followed by summer (36.00±0.70 hours) and rainy season (35.54±0.80 hours), respectively. Higher percentage of normal estrus was observed during rainy season (79.31%) when compared to winter (72.73%) and summer (53.33%). On the other hand, a greater percentage of short and long estrous cycle was reported in summer followed by winter and rainy season. Moreover, length of estrus and its duration did not differ significantly (P>0.05) with age. The mean of rectal and vaginal temperature during estrus were recorded as 39.30±0.05 °C and 39.60±0.03 °C, respectively. However, seasonal variation on post-partum heat period did not differ significantly (P>0.05). The mean post-partum heat period of Black Bengal does among the seasons was observed as 84.56±3.28 days. The present result on estrus behavior of Black Bengal goat could help to boost up effective artificial insemination of goat population for optimizing productivity under intensive condition.