Laboratory Manual for Classification and Morphology of Rumen Ciliate Protozoa

B.A. Dehority

• Publisher: CRC Press
• Year: 2018
• ISBN:
  9781351090810
• Edition: 1
• Topic: Medicine
• Subtopic: Veterinary Medicine

The only rumen protozoa lab guide featuring line drawings created by a leading scientist in the field
Laboratory Manual for Classification and Morphology of Rumen Ciliate Protozoa is a unique lab guide for learning how to count and identify rumen protozoa. In this guide, Professor Dehority has created line drawings of rumen protozoa that emphasize morphological features and size measurements. The book also provides keys for identifying genera and species, and it contains classifications and descriptions of the different orders and families of rumen ciliate protozoa. Procedures for counting rumen protozoa and identifying individual species are included as well.Laboratory Manual for Classification and Morphology of Rumen Ciliate Protozoa will be an excellent identification guide for protozoologists, microbiologists, dairy scientists, and any researcher or student working with rumen protozoa.

Family Ophryoscolecidae

Morphological Orientation

Considerable discrepancy has arisen over the terminology used to describe the different cell surfaces in the family Ophryoscolecidae. When asymmetrical organisms are not oriented in relation to the force of gravity, describing body sides as “dorsal” and “ventral” is confusing. The system used in this book has been proposed by Lubinsky (1958), and is presented in detail on the next page. The relationship between this system of terminology and the nomenclature of Dogiel (1927) and Kofoid and MacLennan (1930) are shown in the following table:

Subfamilies of Ophryoscolecidae

Subfamily ENTODINIINAE Lubinsky, 1957 - One ciliary zone; one contractile vacuole; in side view, the macronucleus lies between the micronucleus and nearest body side (Fig. 9-1).

Subfamily DIPLODINIINAE Lubinsky, 1957 - Two ciliary zones located in one transverse plane at anterior end of cell; two or more contractile vacuoles; in side view, micronucleus lies between macronucleus and nearest body side; skeletal plates absent or present; body more or less flattened (Fig. 9-2).

Subfamily OPHRYOSCOLECINAE Lubinsky, 1957 - Two ciliary zones, located in different transverse planes; two or more contractile vacuoles; in side view the micronucleus situated between the macronucleus and nearest body side; skeletal plates present; body more or less cylindrical (Fig. 9-3,4,5,6).

Figure 9 Location of ciliary zones in the family OPHRYOSCOLECIDAE (redrawn from Latteur, 1966 and Hungate, 1978).

Subfamily Entodiniinae

Entodinium is the only genus in this subfamily which commonly occurs in the rumen. General features used to classify rumen protozoa into the genus Entodinium and species within the genus are as follows (also see Fig. 10).

1. The presence of a single oral (adorai) ciliary zone.
2. Lack of skeletal plates.
3. Position of macronucleus - lies between micronucleus and closest body side.
4. Position of the contractile vacuole.
5. Body length - Body length is designated as the distance between the anterior pole of the body and the anal opening.
6. Body width.
7. Ratio of body length to body width (L/W).
8. Length of macronucleus - The distance, on a straight line, between the anterior and posterior tips.
9. Shape of macronucleus.
10. Location of micronucleus.
11. Overall shape of cell.

Figure 10 Cell morphology of protozoa in the genus Entodinium

Figure 11 Variation in caudal spination within an Entodinium species (redraw after Lubinsky, 1957)

Key for Commonly Occurring Species of Entodinium

1. With one or more caudal spine-like projections.................... 2
   Without caudal spine-like projections.................... 7
2. Single heavy spine on posterior left side; contractile vacuole directly anterior of macronucleus.................... Entodinium rostratum
   One long spine on posterior right side; one or more lobes on posterior left side.................... 3
3. Contractile vacuole adjacent to anterior left edge of macronucleus.................... 4
   Contractile vacuole near middle of body to the left of triangular groove on right side of upper surface.................... 5
   Contractile vacuole near middle of body, to the left of distinct narrow groove on right side of upper surface, which extends anteriorly to outer adorai lip.................... 6
4. A pointed to slightly rounded lobe on posterior left side .................... Entodinium caudatum forma loboso-spinosum
   Pointed to slightly rounded lobes on both upper and lower posterior left side.................... Entodinium caudatum forma caudatum
5. A pointed to slightly rounded lobe on posterior left side ..........

Table of contents

• Cover
• Title Page
• Copyright Page
• Contents
• Preface
• Classification of Rumen Ciliate Protozoa
• Key for Identifying Genera of Rumen Protozoa
• Rumen Protozoa in the Orders Prostomatida (Family Buetschliidae) and Trichostomatida (Families Isotrichidae and Blepharocorythidae)
• Rumen Protozoa in the Order Entodiniomorphida
• Family Ophryoscolecidae
• Procedure for Counting Total Protozoan Numbers in Rumen Contents