Effect of hemoglobin type on the cardiorespiratory system of sheep

Dawson, Terence J.; Evans, J. V.

doi:10.1152/ajplegacy.1965.209.3.593

Cited by 28 publications

(18 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…are similar to those reported for anaesthetized sheep by Dawson and Evans (1967), while those obtained during disturbance (9-6 g/100 ml ± 0-6 S.D.) approximate values published for conscious sheep (Holman, 1944;Tod, Wyant, Stone and Elam, 1952;Dawson and Evans, 1965). In our study the increase in jngular haemoglobin eoneentration during disturbance varied from test to test, ranging between 12^ and 30%.…”

Section: Discussionsupporting

confidence: 92%

Contraction of the Sheep's Spleen

Dooley

Hecker

Webster

1972

Aust J Exp Biol Med

View full text Add to dashboard Cite

Summary Changes in the thickness of the spleen and associated alterations in the haemoglobin concentration in jugular venous blood were studied in undisturbed and excited conscious sheep. Decreases in spleen thickness were induced by single injections of adrenaline (1·4 to 35·5 μg/kg), and by disturbance. The increase in jugular vein haemoglobin concentration following splenic contraction returned to control levels after spleen thickness resumed its control value. However, the responses of these two variables differed markedly among sheep both to a given dose of adrenaline and to progressively higher adrenaline dosage. Respiratory events, feeding, changes in rumen pressure and in posture each induced characteristic variations in spleen thickness. No changes in spleen thickness were observed in conscious undisturbed sheep. Neither disturbance nor adrenaline injections altered the jugular haemoglobin concentration in splenectomized sheep.

show abstract

Section: Discussionsupporting

confidence: 92%

Contraction of the Sheep's Spleen

Dooley

Hecker

Webster

1972

Aust J Exp Biol Med

View full text Add to dashboard Cite

show abstract

“…Other physiological parameters relative to oxygen affinity have been examined. Dawson & Evans (1965) found that both the arterial and venous bloods of sheep with HbA were significantly more saturated with oxygen than those of sheep with HbB. Also the former sheep had a larger blood volume, and higher values for haemoglobin and packed cell volume than the latter.…”

Section: ( 5 ) Possible Signijicance Of Haemoglobin Polymorphismmentioning

confidence: 86%

Genetic Variation in the Sheep Red Blood Cell

Tucker¹

1971

Biological Reviews

View full text Add to dashboard Cite

Summary 1. There are 7 well‐established red‐cell antigen (blood group) loci. The R‐O system has 3 phenotypes, R, O and i, identified by the ‘naturally occurring’ antibodies, anti‐R and anti‐O. The R and O substances are also present in soluble form in some body secretions. The expression of R and O is controlled by a dominant gene I, epistatic in effect, at an independent locus from that of R. The systems, A, C, M‐L, B, D and X‐2 are identified by means of ‘immune‐type’ antibodies, and several of the loci have multiple alleles. An isoenzymic form of serum alkaline phosphatase is associated with the R‐O system. The frequency for the genes at the various loci has been determined in a limited number of breeds. 2. Some sheep red cells have high K+ and low Na+ concentrations (HK type, or Key), others have low K+ and high Na+ concentrations (LK type or Kea). Two other rare forms exist; Key type which is HK but with lower than normal K+ values, and Kep type which has approximately equal Na+ and K+ concentrations. The red cells of foetuses and newborn lambs have high K+ levels irrespective of their potassium genotype. HK cells have 3–4 times greater (Na+‐K+)‐activated ATPase activity, a 3–4 times increased rate of active K+ transport and a larger number of ouabain‐binding sites than LK cells. Antigen M is present on homozygous HK and heterozygous LK red cells, and antigen L is present on homozygous and heterozygous LK red cells. Sensitization of LK cells with anti‐L stimulates active K+ transport and ATPase activity and exposes a larger number of ouabain‐binding sites in these cells. Anti‐M has no effect. The red cells of newborn lambs only show weak L and M antigen activity. It is postulated that L antigen inhibits cation transport in LK cells by masking the pump sites on the membrane. Immature red cells in LK‐type sheep have a high rate of active K+ transport and yet have L antigen present. No satisfactory explanation for this has yet been advanced. There is no conclusive evidence that the potassium types have any significance from the point of view of adaptation or sheep breeding. The potassium‐gene frequencies are known for a large number of breeds. 3. Two allelic genes, Hb4 and HbB control 3 haemoglobin phenotypes, A, AB, and B. Foetal haemoglobin (HbF) is present in foetuses and newborn lambs. Sheep with HbA also synthesize small amounts of another haemoglobin (HbC) and under conditions of severe anaemia, synthesis of HbC takes over from that of HbA. No change in HbB is observed in anaemia. A rare haemoglobin (HbD) has been found in 3 Yugoslavian sheep. Hbs A, B, C and F differ in their physicochemical properties; they share the same alpha chains but their non‐alpha chains differ in a number of amino acids. HbD differs from HbA in one amino acid in the alpha chain. Certain genetic aspects are discussed. There is some evidence that sheep with HbA are less fertile than those with HbB. The gene frequencies for Hb are known for a large number of breeds. 4. Two isoenzymic forms of carbonic anhydrase are found in red‐cel...

show abstract

“…This interesting and concentrated distribution of the HBA allele in the Tibetan sheep surveyed may not be related directly with such a phylogenetic study. Rather, it has long been considered that the hemoglobin A component, which is controlled by the HBA allele, has a high affinity for oxygen (Dawson and Evans, 1965) and is important for survival in mountain areas at altitudes over 3000 m. This physiological adaptability will likely be associated with the specific distribution of the HBA allele in the Tibetan sheep group. According to Zhang et al (1988), it has been demonstrated that the frequency of the HBA allele clearly increases with the rise in the altitude of the grazing areas of the Menyuan Tibetan sheep of Qinghai Province.…”

Section: Discussionmentioning

confidence: 99%

Phylogenetic Relationships among Indigenous Sheep Populations in East Asia based on Five Informative Blood Protein and Nonprotein Polymorphisms

Tsunoda

Chang²,

Sun³

et al. 2006

Biochem Genet

View full text Add to dashboard Cite

The phylogenetic relationships among 23 local sheep breeds and varieties in East Asia were determined based on allele frequency data for five informative and polymorphic blood protein and nonprotein loci (transferrin, arylesterase, hemoglobin-beta, X-protein, and potassium transport) using electrophoresis and ion-densitometric techniques. Comparatively striking differences in the frequency distributions, especially of hemoglobin-beta and X-protein alleles, were seen between the northern population of the Khalkhas, Bhyanglung, Baruwal, Jakar, Sakten, and five Chinese breeds and the southern population of the Bengal, Kagi, Lampuchhre, Myanmar, and Sipsu breeds. Clustering analyses using UPGMA and NJ methods and principal component analysis, using the data of all populations and loci tested, clearly demonstrated the difference. The two population groups are divided by the boundary of the Himalayas, and each diverged into three subgroups: Mongolian, Tibetan, and Himalayan groups in the north and Indian groups I, II, and III in the south. It was noted that the genetic differentiation of populations was more distinct in the northern group. These findings strongly suggest the existence of at least two large and phylogenetically different gene pools of sheep in East Asia.

show abstract

Effect of hemoglobin type on the cardiorespiratory system of sheep

Cited by 28 publications

References 0 publications

Contraction of the Sheep's Spleen

Contraction of the Sheep's Spleen

Genetic Variation in the Sheep Red Blood Cell

Phylogenetic Relationships among Indigenous Sheep Populations in East Asia based on Five Informative Blood Protein and Nonprotein Polymorphisms

Contact Info

Product

Resources

About