Iranian Sheep Research Articles

Enzymatic determination of lipids in liver extracts

This study was conducted to investigate the relationship between variation within Calpastatin (CAST) gene and meat quality and fatty acid profiles in fat-tailed (Chall) and thin-tailed (Zel) Iranian sheep breeds using PCR–SSCP, DNA sequence, and genotype, haplotype, and SNP effect analyses. Six previously identified SNPs including C24T, G62A, G65T, and T69- located in intron 5 and c.197A > T and c.282G > T localized in exon 6 were observed. These SNPs constituted six haplotypes of CAST-1, CAST-2, CAST-6, CAST-8, CAST-10, and CAST-11, corresponding to six genotypes of “B”, “C”, “D”, “F”, “I”, and “J”. Animals inheriting genotype “I” had lower value of shear force (P < 0.03), concentration of palmitic acid (P < 0.05), cholesterol (P < 0.05), and n−6:n−3 ratio (P < 0.02), and higher content of palmitoleic acid (P < 0.04) compared to those inheriting the other genotypes. Also, animals containing one copy of CAST-10 haplotype showed lower value of shear force (P < 0.005), lower n−6:n−3 ratio (P < 0.02), higher concentration of palmitoleic acid (P<0.04) and total mono-unsaturated fatty acid (P < 0.02) than those containing the other haplotypes. SNP effect analyses showed that three SNPs including G62A, G65T, and c.197A>T had significant effects on the content of some fatty acids and their selected ratios (P < 0.05 to P < 0.001), shear force (P = 0.006 and P < 0.001), and the cholesterol content of longissimus dorsi muscle (P < 0.05). Overall, it seems that genotype “I”, haplotype CAST-10, the “AA” genotype of SNP G62A, and the “GT” genotype of G65T SNP were the most desirable genotypes and haplotype when selecting lambs in terms of both tenderness and fatty acid composition of meat, because selecting these genotypes and this haplotype would increase tenderness and proportion of healthy fatty acids, and also decrease proportion of harmful fatty acids of meat.

Effects of tail fat on induction and recovery of sheep anesthetized with halothane

The study used 12 fat-tailed Iranian sheep, which were mask induced with halothane without premedication and maintained under anesthesia for 1 h. Fourteen days later, eight of these sheep were subjected to fat tail amputation using local epidural anesthesia. Finally, 20 days after tail amputation, all 12 sheep were reanesthetized similarly using the same protocol as the first anesthesia. Removal of stored fat in the tail induced a decrease ( P < 0.05) in recovery time and required less halothane consumption during 1 h of general anesthesia. Activity of AST (aspartate aminotransferase) and ALT (alanine aminotransferase) in blood increased ( P < 0.05) during the first 48 h after recovery in sheep with fat tail compared with sheep without fat tail. In this study fat tail sheep were used as animal model of human obesity. It was concluded that stored fat in fat tail sheep increased recovery time from anesthesia and increased halothane uptake during the anesthetic maintenance period. Therefore precautions should be taken when anesthetizing fat tail sheep.

Observations on cloisonné kidney in sheep

Abstract Extract Cloisonne kidney, though considered to be a non-clinical entity, has a pathological significance in certain animals, as has been reported in goats from many countries (1) (2) . Pigmentation of renal cortical tubules has also been observed in horsesc (4) . However, no reports are yet available on such a condition in sheep. This communication therefore presents observations on cloisonne kidney in an Iranian sheep.

Changes in the Termination of Spinal Cord at Vertebral Levels during Pre- and Postnatal Development of Sheep

Abstract Ghazi, S.R. and Gholami, S. 1993. Changes in the termination of spinal cord at vertebral levels during pre- and postnatal development of sheep. J. Appl. Anim. Res., 4: 61–66. The site of termination of spinal cord in respect of the vertebral level was studied during the pre- and postnatal development in both sexes of local Iranian sheep. The changes in the termination of spinal cord were observed with the age of the animal. In early life of 3 months gestation, the maximum termination was at the level of caudal third of the third sacral vertebra and then it went on changing with the advancement of age during pre- and postnatal life even up to adult age of the animal In the adult sheep, aged 1–4 years, the spinal cord terminated at the level of first and second sacral vertebrae. It was also observed that the recession of the cord was more towards caudal level in female as compared to male animals.

Nephrolithiasis in Iranian sheep.

Out of 500 Iranian sheep examined, six revealed the presence of lithiasis in their kidneys. Nephroliths in three animals were composed of ammonium magnesium phosphates and in the others of calcium carbonates and calcium phosphates. Interestingly sodium and ammonium urate crystals were present in the kidneys of three animals.

A survey of Mycoplasma arginini and other agents from subacute and chronic ovine pneumonia in Iran

This survey was carried out to find the aetiologic agents of subacute to chronic ovine pneumonia which is ranked amongst the most prevalent disease syndromes of sheep in Iran. Mycoplasma arginini was isolated from 79% (49 out of 62) of pneumonic lungs. The higher frequency of M. arginini in pneumonic lungs (79%), compared with its low prevalence in apparently normal ones (6.5%), and the type of histopathologic reactions observed in affected tissues, indicate that this agent might have an important role in producing ovine pneumonia. In some cases, other bacteria such as Pasteurella multocida, Pasteurella haemolytica, Streptococcus sp. and Corynebacterium sp. were isolated. Cultures for viruses were negative and, according to histopathologic examinations, there was no evidence of chlamydial infection. Dictyocaulus filaria and Protostrongylus rufescens were isolated from lungs with verminous pneumonia.

Disruptive mating behavior by subadult Armenian wild sheep in Iran

The mating behavior of an insular Armenian wild sheep population ( Ovis orientalis gmelini) and a Transcaspian urial ( Ovis orientalis arkal) population was quantified during the rutting season in December 1972, and November and December 1973, respectively. Males were grouped into two age classes; Class I (≤ 4 years) and Class II (≥ 5 years). Typically, older rams prevent younger rams from participating in the rut through threatening gestures; subadult rams will not ordinarily challenge adult rams as was the case in the Transcaspian population. In the Armenian population, subadult rams hurriedly approached ewes and chased and mounted ewes. Subadult Armenian rams disrupted the social stability of the population resulting in wasted energy, particularly in ewes, at a critical time of the year. Wildlife managers should monitor wild ungulate populations to determine if such disruptions are occurring and develop preventative management strategies.

Abortion due to Brucella abortus in Sheep in Iran

Summary: A study on natural Brucella abortus infection in sheep was carried out from 1983 to 1987 at the Razi Institute in Iran. A total of 636 fetuses from sheep were examined bacteriologically and B. abortus was isolated from 6 (1%) cases. All isolates were classified by biotype procedures and were B. abortus biotype 3. It was postulated that sheep may act as a reservoir of B. abortus infection for cattle.

Characterization of Clostridium oedematiens Strains Isolated from Cases of Black Disease of Sheep in Iran

Characterization of Clostridium oedematiens Strains Isolated from Cases of Black Disease of Sheep in Iran

Abortion due to Brucella Abortus in sheep in Iran

Summary: A study on natural Brucella abortus infection in sheep was carried out from 1983 to 1987 at the Razi Institute in Iran. A total of 636 fetuses from sheep were examined bacteriologically and B. abortus was isolated from 6 (1%) cases. All isolates were classified by biotype procedures and were B. abortus biotype 3. It was postulated that sheep may act as a reservoir of B. abortus infection for cattle.

Distribution and toxicity of monosodium methanearsonate following oral administration of the herbicide to dairy sheep and goats.

Iranian fat-tailed sheep and dairy goats were administered the herbicide monosodium methanearsonate orally at a dose of 10 mg. MSMA (as arsenic) per kg. of body weight. The concentration time curves of MSMA in the blood of sheep and goats followed a first order composite exponential equation of the form: Cb(t) = Ae- alpha t + Be- beta t - C degrees be-kat. Absorption, distribution and elimination of MSMA, therefore, corresponds to an open two-compartment model. Arsenic from MSMA was readily absorbed from gastrointestinal tract and distributed in the body fluids and the various tissues. Approximately 90% of the arsenic was excreted in the urine within 120 hrs and small amounts were also recovered in feces. Arsenic accumulation in the tissues was low and urinary excretion was the most important exit route. Arsenic concentrations in milk were low when compared to the controls, which indicates that arsenic is not excreted in the milk to significant levels. The absorption, distribution and overall elimination rate constants for the two animal species studied were statistically different at the 0.95 level of confidence which indicates that there are apparently differences in MSMA metabolism by sheep and goats.

Diagnosis of Johne's disease in sheep by counter-immunoelectrophoresis.

The use of counter-immunoelectrophoresis (CIEP) in the diagnosis of Johne's disease was investigated in flocks of sheep in Iran and Libya. In 50 sheep with no history of paratuberculosis none had antibodies to Mycobacterium paratuberculosis. Animals vaccinated as neonates were either negative or had reciprocal titres (RT) of less than 4 at 18 months of age unless exposed to infection. Among 105 non-vaccinated adults in an infected flock 91% had antibodies. Twenty-one animals that either died or were slaughtered were autopsied. Eight animals with RT of 8 or above and one with RT of 4 had gross lesions with demonstrable acid-fast organisms. Two animals with RT of 2 had clinical disease while three with RT of 4 and one with RT of 2 had histopathological lesions only. All animals found negative for M. paratuberculosis infection had RT of 2 or below. The critical interpretation of the test is discussed.

Isolation and typing of Clostridium oedematiens (Cl. novyi) from cases of black disease of sheep in Iran

Abstract Clostridium oedematiens types A, B and D have been isolated from liver lesions of 44 cases of black disease of sheep in Iran. The technique of isolation and identification by using fluorescent labelled antibodies is described. The isolates were typed based on their lecithinase, haemolytic, necrotic and lethal activities.

Histopathology of liver in Iranian sheep naturally infected with Dicrocoelium dendriticum.

The gross pathology and histopathology was investigated in 100 sheep livers heavily infected with Dicrocoelium dendriticum. The livers were indurated, heavily scarred and superficially lumpy. The bile ducts were thickened, dilated and in some areas sacculated. There were no migratory lesions in the liver parenchyma, but extensive proliferation of the glandular structures of the main ducts was seen. The portal areas and the walls of the ducts showed marked infiltration with lymphocytes, plasma cells, macrophages and eosinophils. In smaller ducts with a rather chronic phase of infestation there was considerable papillary proliferation of the mucosa and sometimes the lumen was partially blocked by these papillae. Cholangitis from secondary bacterial infection was observed. In the terminal stages of the disease the gross picture resembles portal cirrhosis with destruction of the liver cells by fibrosis.

Babesia crassa n.sp. (Sporozoa, Babesiidae) of domestic sheep in Iran.

A large Babesia sp., isolated from a sheep in Iran, provided to be serologically and morphologically different from B, motasi and B. ovis. The parasite, designated B. crassa n. sp., is characterized by the frequent occurrence of four organisms in one erythrocyte, which is the result of quadruple division and, in other cases, of two successive binary divisions. Parasited resulting from the first of two successive binary divisions are exceptionally broad. B. crassa appears to be of low pathogenicity for sheep and goats, to which it is also infective. The vector is unknown.

Isolation and typing of Clostridium oedematiens (Cl. novyi) from cases of black disease of sheep in iran

Clostridium oedematiens types A, B and D have been isolated from liver lesions of 44 cases of black disease of sheep in Iran. The technique of isolation and identification by using fluorescent labelled antibodies is described. The isolates were typed based on their lecithinase, haemolytic, necrotic and lethal activities.

The relationships between pre- and post-weaning growth traits in lambs of Iranian fat-tailed sheep and their crosses with Corriedale and Targhee rams

ABSTRACTThe pre-weaning records (birth weight, weaning weight and gain from birth to weaning) of 291 male and female lambs and the post-weaning records (body weight, feedlot gain and food conversion) of 136 male lambs were used to study relationships between different traits. The lambs were derived from three fat-tailed Iranian sheep breeds (Karakul, Mehraban and Naeini) and their crosses with Corriedale and Targhee rams. All lambs were weaned at 75 + 5 days of age and the males were fed in a feedlot for 100 days after weaning. Feedlot measurements were taken at 20-day intervals.Weaning weight and pre-weaning average daily gain showed positive and significant associations with birth weight. Birth weight, weaning weight and gain from birth to weaning were positively associated with body weight at subsequent ages in feedlot as well as with final weight (P&lt;0·01). Birth weight, weaning weight and pre-weaning average daily gain were positively and significantly associated with total feedlot gain.Of the different traits, total gain during the first 20 days in feedlot (adjust period) had the lowest and total gain during the second 20 days had the highest association with total feedlot daily gain. There was no evidence that the heavier lambs at weaning and those showing high growth rate before weaning, were more efficient in the feedlot. Gain during the second 20-day period in the feedlot had a significant negative association with the total food conversion (unit food/unit gain) and therefore was a good predictor for food conversion.When the feedlot period was divided into two 40-day periods, it was found that gain during both had a significant negative association with the corresponding food conversion. A similar association was observed between total feedlot gain and food conversion, indicating that the rate and efficiency of gain improved simultaneously.

Evolution of Wild Sheep in Iran

Evolution of Wild Sheep in Iran

Mycotic dermatitis of sheep in Iran

Mycotic dermatitis of sheep in Iran

Population Decline of an Insular Population of Armenian Wild Sheep in Iran

From 1970 to 1973, an insular population of Armenian wild sheep (Ovis orientalis gmelinii) in an area of 3145 hectares declined from an estimated 3500 to 1000. The dry spring and summer of 1971, the severe winter of 1971-72, and the poor range conditions engendered by heavy overstocking were the major factors contributing to the 1971-72 die-off. During that die-off less than 1 percent of the lamb crop survived. Net productivity during 1971, 1972, and 1973 was 14 percent, less than 1 percent, and 15 percent respectively. Under present poor range conditions, the recommended population level is 500 animals. J. WILDL. MANAGE. 41(4):720-725 Kabudan Island, situated in northwestern Iran (Fig. 1), is inhabitated by a population of Armenian wild sheep which were introduced in unknown numbers from the mainland in the nineteenth century (Nasonov 1923). When the island was declared a wildlife refuge in 1967, all domestic sheep and goat grazing was prohibited. Except for 2 game wardens who patrol the area, there are no permanent human inhabitants on the island. To establish natural predation, an adult male and female leopard (Panthera pardus) trapped in northeastern Iran were introduced on the island in 1969. Limited hunting of wild sheep was allowed on the island until 1973. The population dynamics of the wild sheep population were documented between May 1971 and May 1975. We thank the Iran Department of the Environment field personnel for their assistance and in particular the Director, H. E. Eskandar Firouz, for his support of these studies.