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Parental Behavior And Some Histological Features Of Scales In Cichlasoma Citrinellum (Pisces, Cichlidae), David L. G. Noakes Jan 1976

Parental Behavior And Some Histological Features Of Scales In Cichlasoma Citrinellum (Pisces, Cichlidae), David L. G. Noakes

Investigations of the Ichthyofauna of Nicaraguan Lakes

We have described elsewhere the ontogeny of behavior of young Cichlasoma citrinelium, and some aspects of the behavior of the parents during the corresponding period (Noakes and Barlow 1968, 1973a, 1973b). Adults are polymorphic in body color, the "normal" color being grey; the "gold" morphs are more or less xanthic and lack the species typical dark markings (Barlow 1973; and in preparation). The young have a characteristic behavior directed toward the parents in both the laboratory and the field. About 4 days after the young become free-swimming, they begin to feed from the body surfaces …


Movement Of Bull Sharks, Carcharhinus Leucas, Between Carribean Sea And Lake Nicaragua Demonstrated By Tagging, Thomas B. Thorson Jan 1976

Movement Of Bull Sharks, Carcharhinus Leucas, Between Carribean Sea And Lake Nicaragua Demonstrated By Tagging, Thomas B. Thorson

Investigations of the Ichthyofauna of Nicaraguan Lakes

The shark that occurs in the fresh water of Lake Nicaragua and the Rio San Juan was first described (as Eulamia nicaraguensis) by Gill and Bransford (1877). These authors also first proposed the theory that the sharks, as well as the sawfish and tarpon that occur in the lake, were trapped there by late Pleistocene volcanic activity, which isolated a former bay of the Pacific and resulted in the formation of the present lake. The theory of a landlocked, distinct species, of Pacific origin, has en joyed wide popular acceptance and for many years was also accepted by professional …


The Behavior And Ecology Of Herotilapia Multispinosa (Teleostei, Cichlidae), Jeffrey R. Baylis Jan 1976

The Behavior And Ecology Of Herotilapia Multispinosa (Teleostei, Cichlidae), Jeffrey R. Baylis

Investigations of the Ichthyofauna of Nicaraguan Lakes

Because of their complex social behavior and the ease with which they can be manipulated, cichlid fishes have long been of special interest to the ethologist. However, most of the research into cichlid behavior has been on Old World species. The social behavior of New World species is different and deserves more study. This paper will describe the ethology of one of the Central American cichlids, Herotilapia multispinosa.


Studio Istochimico Comparato Della Ghiandoia Digitiforme Rettale Di Selaci Marini E Di Acqua Dolce, Giuseppe Gerzeli, Gian Franco De Stefano Jan 1976

Studio Istochimico Comparato Della Ghiandoia Digitiforme Rettale Di Selaci Marini E Di Acqua Dolce, Giuseppe Gerzeli, Gian Franco De Stefano

Investigations of the Ichthyofauna of Nicaraguan Lakes

La ghiandola reHale dei Selaci secerne notevoli quantita eli elettroliti: I'inelagine istomorfologica e istochimica puo consentire eli documentare I'('sistenza eli elispositivi strutturali e di potenzialita metaboliche collegabili con I'accumulo e la liberazione eli energia utilizzabile per un trasporto ionico attivo, fenomeno che appare alIa base deIl'attivita della ghiandola.


Aspetti Della Ghiandola Rettale E Della Regolazione Osmoticain Selaci Marini E D' Acqua Dolce, Giuseppe Gerzeli, Maria Victoria Gervaso, Gian Francis De Stefano Jan 1976

Aspetti Della Ghiandola Rettale E Della Regolazione Osmoticain Selaci Marini E D' Acqua Dolce, Giuseppe Gerzeli, Maria Victoria Gervaso, Gian Francis De Stefano

Investigations of the Ichthyofauna of Nicaraguan Lakes

In continuazione di ricerche giil pubblicate (GERZELI G., 1967 - 1st. Lombardo Rend. Sc., BIOI: 117 ; GERZELI F. e DE STEFANO G. F., 1968 - Cony. Soc. Ital. Anat.) l'indagine istomorfologica e istochimica sulla ghiandola rettale c stata estes a ad altre specie, integrandola con alcuni dati ehimici su costituenti plasmatici. Sinora sono state esaminate Ie seguenti specie: Scylliorhinus stellaris, Galeus melastomus, Torpedo marmorata, Raja asterias (del Mar Tirreno); Galeorhinus zyopterus (dell'Oceano Pacifico orientale) ; Carcharhinus leucas (del Mar dei Caraibi e del Lago di Nicaragua) ; Pristis perotteti (del Lago di Nicaragua) ; Potamotrygon brachiurus …


Helminths From Elasmobranchs In Central American Fresh Waters, Donald E. Watson, Thomas B. Thorson Jan 1976

Helminths From Elasmobranchs In Central American Fresh Waters, Donald E. Watson, Thomas B. Thorson

Investigations of the Ichthyofauna of Nicaraguan Lakes

Five species of monogeneans and 14 species of cestodes are reported from two elasmobranch species in fresh waters of Guatemala, Nicaragua and Costa Rica. Monogeneans from the bull shark, Carcharhinus leucas (Muller and Henle, 1841), are: Dermophthirius maccallumi n. sp. (Microbothriidae); Heteronchocotyle leucas Hargis, 1955 and Erpocotyle carcharhini n. sp. (Hexabothriidae). Cestodes from the bull shark are: Phyllobothrium lactuca van Beneden, 1850, P. leuci n. sp., P. nicaraguensis n. sp., Anthobothrium cornucopia van Beneden, 1850, A. laciniatum Linton, 1890 (Phyllobothriidae): Platybothrium hypoprioni Potter, 1937, Phoreiobothrium triloculatum Linton, 1901 (Onchobothriidae); Cathetocephalus thatcheri Dailey and Overstreet, 1973 (Cathetocephalidae); Dasyrhynchus variouncinnatus (Linton, 1924) …


Ec76-218 1976 Nebraska Beef Cattle Report Jan 1976

Ec76-218 1976 Nebraska Beef Cattle Report

University of Nebraska-Lincoln Extension: Historical Materials

Extension Circular 76-218 is the 1976 Nebraska beef cattle report.


Farm, Ranch And Home Quarterly Institute Of Agriculture And Natural Resources, University Of Nebraska- Lincoln Jan 1976

Farm, Ranch And Home Quarterly Institute Of Agriculture And Natural Resources, University Of Nebraska- Lincoln

Farm, Ranch and Home Quarterly

In this issue:

2 Scientists Trace Ancient Nitrogen in Deep Nebraska Soils

4 Backyard Farmer

5 Children's Imaginary Playmates

7 New Landscape Design Courses

9 New Wildflower Varieties Released

11 Fabric Softener Stains

12 4.-H'ers Become Trained Communication

14 A New Look at Animal Wastes as Fertilizer

16 Black Layer Signals Maturity

18 Roadside Hay Harvests

19 Protein and Lysine Enriched Bread


G76-325 Sweet Clover Poisoning, I,A. Schipper Jan 1976

G76-325 Sweet Clover Poisoning, I,A. Schipper

University of Nebraska-Lincoln Extension: Historical Materials

Sweet clover poisoning is a problem of varying frequency and intensity in livestock wherever sweet clover grows. The toxic compound produced in sweet clover prevents normal blood clotting resulting in hemorrhages and associated symptoms.

This publication covers which animals are most susceptible, the cause, prevention, management, and treatment of sweet clover poisoning.


Supplemental Value Of Feed Grade Biuret And Urea-Molasses For Cows On Dry Winter Grass, Ivan G. Rush, Robert Totusek Jan 1976

Supplemental Value Of Feed Grade Biuret And Urea-Molasses For Cows On Dry Winter Grass, Ivan G. Rush, Robert Totusek

Panhandle Research and Extension Center

Four trials were conducted to evaluate the supplemental value of feed grade biuret (in dry supplements) and urea (in liquid urea-molasses mixtures) when compared to natural protein and urea in dry supplements for beef cows grazing low quality dry winter range grass. Urea or feed grade biuret provided 50% of the nitrogen in 30% CP dry supplements and urea provided 50% of the nitrogen in 30% CP dry supplements and urea provided 94% of the nitrogen in 30% CP liquid supplements. Dry supplements were self-fed with salt added to limit intake.

Winter weight loss of cows fed dry urea-containing supplements …


Evaluation Of Beef Cattle Range Supplements Containing Urea And Biuret, Ivan G. Rush, R. R. Johnson, Robert Totusek Jan 1976

Evaluation Of Beef Cattle Range Supplements Containing Urea And Biuret, Ivan G. Rush, R. R. Johnson, Robert Totusek

Panhandle Research and Extension Center

Two winter trials were conducted with 304 lactating range cows on dry grass to evaluate non-protein-nitrogen (NPN) in 30% protein supplements containing biuret (pure and feed grade), urea and extruded grain-urea. The NPN sources contributed one-half of the supplemental nitrogen with natural 15 and 30% protein supplements serving as negative and positive controls.
Winter weight loss of cows was greater (P~.02) on the negative than on the positive control in both trials. The apparent utilization of all NPN sources was low and the utilization of urea and extruded grain-urea was less than pure or feed grade biuret. Rumen biuretolytic activity …


Limnology Of The Great Lakes Of Nicaragua, Gerald A. Cole Jan 1976

Limnology Of The Great Lakes Of Nicaragua, Gerald A. Cole

Investigations of the Ichthyofauna of Nicaraguan Lakes

For more than a century, the two largest bodies of water in Nicaragua, Lake Nicaragua and its smaller companion, Managua, have engaged naturalists from several disciplines. Perhaps their appeal has been as curiosities because of the occurrence of fish with marine affinities in the larger lake, especially a dangerous shark. The charm has been in Nicaragua or Cocibolca, rather than Managua, properly called Xolotlán. Even though the latter is saltier, it has no elasmobranchs or tarpons.
The lakes, and specifically the larger, cover the greatest expanse of any body of water between Lake Titicaca, Bolivia-Peru, and the Laurentian …


Geography Of Lake Nicaragua, Jaime Incer Jan 1976

Geography Of Lake Nicaragua, Jaime Incer

Investigations of the Ichthyofauna of Nicaraguan Lakes

The area surrounding Lake Nicaragua is discussed from the standpoints of its history, geological setting, climate and vegetation. A physical description of the lake itself is given, including the nature of its bottom, its shoreline, its islands and volcanoes.


The Status Of The Lake Nicaragua Shark: An Updated Appraisal, Thomas B. Thorson Jan 1976

The Status Of The Lake Nicaragua Shark: An Updated Appraisal, Thomas B. Thorson

Investigations of the Ichthyofauna of Nicaraguan Lakes

Since 1966, an extensive tagging program has demonstrated beyond any further doubt (Thorson, 1971) that the sharks move from the Caribbean Sea to Lake Nicaragua and vice versa. At the time of this writing, of 1450 post-juvenile sharks tagged at the various river mouths on the Caribbean Coast, ten have been recovered in Lake Nicaragua; and of 146 tagged at San Carlos, where the river leaves the lake, 28 have been recovered along the Caribbean Coast, most of them at the various outlets of the Rio San Juan. Except for these basic facts, the results of the tagging program have …


The Midas Cichlid In Nicaragua, George W. Barlow Jan 1976

The Midas Cichlid In Nicaragua, George W. Barlow

Investigations of the Ichthyofauna of Nicaraguan Lakes

Cichlasoma citrinellum (Gunther), the Midas cichlid, is the most important food fish in the Great Lakes Basin of Nicaragua. It occurs in the majority of the lakes, where it is the most ubiquitous cichlid fish, but it is uncommon in the rivers. The fry are carnivorous while the juveniles and adults are omnivorous, eating mostly Aufwuchs, snails, and fish. The Midas cichlids suffer from a number of diseases in nature and in the laboratory, including lymphocystis and nocardiosis. Potential predators vary from sharks and sawfish in Lake Nicaragua, to just one cichlid relative in one crater lake; in Lake …


Calcium And Other Ions In Blood And Skeleton Of Nicaraguan Fresh-Water Shark, Marshall R. Urist Jan 1976

Calcium And Other Ions In Blood And Skeleton Of Nicaraguan Fresh-Water Shark, Marshall R. Urist

Investigations of the Ichthyofauna of Nicaraguan Lakes

The bull shark, Carcharhinus lellcas, employing archaic but effective means of regulating the physical-chemical composition of its body fluids, thrives in tropical fresh-water rivers and lakes. The ionic strength of the serum and the concentrations of total solutes, calcium, urea, and other ions are below the levels found in marine elasmobranchs but higher than the levels in teleosts. The patterns of the calcium deposits of the vertebrae are identical in marine and fresh-water subspecies.


Carcharhinus Nicaraguensis, A Synonym Of The Bull Shark, C. Leucas, Henry B. Bigelow, William C. Schroeder Jan 1976

Carcharhinus Nicaraguensis, A Synonym Of The Bull Shark, C. Leucas, Henry B. Bigelow, William C. Schroeder

Investigations of the Ichthyofauna of Nicaraguan Lakes

Nicaraguensis very closely resembles leucas by the following characters. The anterior margin of the eye is posterior to the front of the mouth by a distance equal to half its own diameter in nicaraguensis; the gill openings are relatively somewhat longer in nicaraguensis, the third being nearly as long as the distance between the nostrils; the free tip of the second dorsal is about two-thirds as long as its base in nicaraguensis.


Reproduction Of The Bull Shark, Carcharhinus Leu Cas , In The Lake Nicaragua-Rio San Juan System, Norman H. Jenson Jan 1976

Reproduction Of The Bull Shark, Carcharhinus Leu Cas , In The Lake Nicaragua-Rio San Juan System, Norman H. Jenson

Investigations of the Ichthyofauna of Nicaraguan Lakes

Carcharhinus leucas, the bull shark, or cub shark, is a member of a large family, the Carcharhinidae, sometimes called requiem sharks. It is of medium size, reaching a maximum of a little more than three meters in some parts of its range, but little more than two and one-half meters in my study area. It is euryhaline, able to live for extended periods of time in both freshwater and marine environments. It is a viviparous shark, retaining the young and nourishing them by means of a yolk-sac placenta.


Namru-3 Translations Of Parasite Literature From Russian, French, Japanese, Etc. Into English (1945-1976) T1101-T1200, United States Naval Medical Research Unit Number Three, Cairo, Medical Zoology Department Jan 1976

Namru-3 Translations Of Parasite Literature From Russian, French, Japanese, Etc. Into English (1945-1976) T1101-T1200, United States Naval Medical Research Unit Number Three, Cairo, Medical Zoology Department

United States Naval Medical Research Unit 3: Publications

T1101. TRANSLATION FROM RUSSIAN. SUMMARY. MIRONOV, P. (1953). Hemorrhagic fever in Burgas Region. Suvrem. Med., Sof., 6:62-73. (In Bulgarian).

T1102. TRANSLATION FROM RUSSIAN. MATEVOSYAN, K. Sh., KARASEVA, P. S., RESHETNIKOV, I. A. and SEMENOV, B. F. (1972). Investigation of arboviruses transmitted through ticks in Armenian SSR. In: Actual problems of virology and prophylaxis of viral diseases, edited by Chumakov, M. P. Tezisy 17. Nauch. Sess. Inst. Posvyashch. Aktual. Probl. Virus. Profilakt. Virus. Zabolev. (Moscow, October 1972), p. 303.

T1103. TRANSLATION FROM RUSSIAN. SKOFERTSA, P. G., GAIDAMOVICH, S. Ya., OBUKHOVA, V. O., KORCHMAR'. N. D., YAROVOI, P. I., KLISENKO, G. A. …


Agricultural Experiment Station News January 1976 Jan 1976

Agricultural Experiment Station News January 1976

Agricultural Research Division: News and Annual Reports

CONTENTS:
FROM THE ACTING DIRECTOR'S DESK
PERSONNEL ACTIONS
GRANTS AND CONTRACTS
GENERAL NOTES
NEBRASKA AGRICULTURAL EXPERIMENT STATION PUBLICATIONS - December 1975
BULLETINS PRINTED


Bottom Sediments Of Lake Nicaragua And Lake Managua, Western Nicaragua, Frederick M. Swain Jan 1976

Bottom Sediments Of Lake Nicaragua And Lake Managua, Western Nicaragua, Frederick M. Swain

Investigations of the Ichthyofauna of Nicaraguan Lakes

Lakes Nicaragua and Managua are large, rather shallow, fresh-water bodies that lie in a late Tertiary and Quaternary graben in western Nicaragua.
The bottom sediments comprise highly organic diatomaceous volcanic silts and clays in which quartz plagioclase feldspar, dioctahedral montmorillonite and volcanic glass are the principal constituents.
Organic nitrogen content of the lake sediments ranges from 0.3-1.2 percent, about the same range as in eutrophic lakes of higher latitudes. Bitumen content is rather low, much like that of oligotrophic lakes. Hydrocarbon fractions of bitumens are similar in amount to an alkaline lake of western U. S. Non-hydrocarbon bitumens are high …


Presence Of The Cichlid Fish Cichlasoma Managuense Gunther In Lake Xiloá, Nicaragua, Jime Villa Jan 1976

Presence Of The Cichlid Fish Cichlasoma Managuense Gunther In Lake Xiloá, Nicaragua, Jime Villa

Investigations of the Ichthyofauna of Nicaraguan Lakes

Villa (1968) included C. managuense in the fauna of Lake Xiloá as a "recently introduced" species since the Ministerio de Agricultura y Ganaderia (Nicaragua) had introduced several hundred young individuals of this species from Lake Managua, hatched at the Estacion Experimental "La Calera." Apparently officials of the Ministerio did not determine whether or not C. managuense occurred in Lake Xiloá prior to its introduction.


Competition Between Color Morphs Of The Polychromatic Midas Cichlid Cichlasoma Citrinellum, George W. Barlow Jan 1976

Competition Between Color Morphs Of The Polychromatic Midas Cichlid Cichlasoma Citrinellum, George W. Barlow

Investigations of the Ichthyofauna of Nicaraguan Lakes

The Midas cichlid, Cichlasoma citrinellum, is a polychromatic fish that occurs in Nicaragua. All of these fish start life as normally colored, cryptic individuals. In some populations a few fish change into conspicuously colored morphs, most frequently gold. When kept in unmixed color groups, golds and normals grow at the same rate; but when they are mixed, growth of the golds becomes taster and that of the normals slower. Golds dominate normals in contests over food, which accounts for their advantage.


Hemoglobin Stability In Bull Sharks, Jack D. Burke Jan 1976

Hemoglobin Stability In Bull Sharks, Jack D. Burke

Investigations of the Ichthyofauna of Nicaraguan Lakes

No significant differences in oxyhemoglobin affinity, or electrophoretic patterns of hemoglobin were found in 18 bull sharks collected in selected regions of Lake Nicaragua, the Rio San Juan, and the Caribbean Sea. The half-saturation of hemoglobin with oxygen (P50) was 11 and 17 mm Hg at pH 7.4 and 6.8, respectively (25° C, 3% hemoglobin solution, potassium phosphate buffer, 0.3 ionic strength). Electrophoresis resolved the hemoglobin into a minor and a major band. P1animetry of densitometric recordings showed that the major band constituted 54% of the total hemoglobin; the minor band, 46%. On the basis of these hemoglobin studies, no …


Body Fluid Solutes Of Juveniles And Adults Of The Euryhaline Bull Shark Carcharhinus Leucas From Freshwater And Saline Environments, Thomas B. Thorson, C. Michael Cowan, Donald E. Watson Jan 1976

Body Fluid Solutes Of Juveniles And Adults Of The Euryhaline Bull Shark Carcharhinus Leucas From Freshwater And Saline Environments, Thomas B. Thorson, C. Michael Cowan, Donald E. Watson

Investigations of the Ichthyofauna of Nicaraguan Lakes

Since the discovery of the phenomenally high urea content of the body fluids of cartilaginous fishes by Staedeler and Frerichs (1858), the unique osmoregulatory system of this vertebrate class has been studied by many investigators. In broad outline, the mechanisms are essentially similar in all three of the major subtaxa: the selachians, the batoids, and the holocephalans. A single exception is the genus Potamotrygon (fresh-water stingrays of South America and Africa), which has apparently lost the ability to concentrate urea even when transferred to salt water.


Rectal Glands Of Marine And Fresh-Water Sharks: Comparative Histology, Mikio Oguri Jan 1976

Rectal Glands Of Marine And Fresh-Water Sharks: Comparative Histology, Mikio Oguri

Investigations of the Ichthyofauna of Nicaraguan Lakes

The rectal glands of elasmobranchs perform the function of salt-excreting organs. These glands are smaller and show regressive changes in specimens of the bull shark, Carcharhinus leucas, found in fresh-water environment, compared with specimens of this and other species from a marine habitat.


Observations On The Reproduction Of The Sawfish, Pristis Perotteti, In Lake Nicaragua, With Recommendations For Its Conservation, Thomas B. Thorson Jan 1976

Observations On The Reproduction Of The Sawfish, Pristis Perotteti, In Lake Nicaragua, With Recommendations For Its Conservation, Thomas B. Thorson

Investigations of the Ichthyofauna of Nicaraguan Lakes

The presently known pristiform fauna of the western Atlantic consists of only two species, one each of Fowler's (1941) subgenera, Pristis and Pristiopsis. The former, characterized by the absence of a subcaudal lobe on the caudal fin, is represented by Pristis pectinatus; the latter, in which the subcaudal lobe is present, by Pristis perotteti. Although several features readily separate the two species, they can most easily be distinguished by the more slender rostrum of P. pectinatus and its larger number of rostral teeth, 24 to 32 on each side, as compared with 14 to 20 in …


Blood And Tissue Identification Of Selected Birds And Mammals, Part Ii: Cross Reaction Patterns Of Birds And Mammals, Using Deer, Bovine, Raccoon, Chicken And Mallard Duck Antiserum, Part 4, David W. Oates, Debra L. Weigel Jan 1976

Blood And Tissue Identification Of Selected Birds And Mammals, Part Ii: Cross Reaction Patterns Of Birds And Mammals, Using Deer, Bovine, Raccoon, Chicken And Mallard Duck Antiserum, Part 4, David W. Oates, Debra L. Weigel

Other Publications in Wildlife Management

Part 4 (pp. 86-114)
Mammals (Figure 10), continued
Horse
Human
Mink
Opossum
Pig
Porcupine.
Prairie Dog
Raccoon
Big Horn Sheep
Domestic Sheep
Striped Skunk
Fox Squirrel
Discussion


Seasonal Changes In Sexual Activity And Serum Levels Of Lh And Testosterone In Finnish Landrace And Suffolk Rams, B. D. Schanbacher, D. D. Lunstra Jan 1976

Seasonal Changes In Sexual Activity And Serum Levels Of Lh And Testosterone In Finnish Landrace And Suffolk Rams, B. D. Schanbacher, D. D. Lunstra

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A procedure for assessing sexual activity (libido) in individual rams is described. Mating activity measured by this procedure and serum levels of luteinizing hormone (LH) and testosterone in Finnish Landrace and Suffolk rams was determined at 8-week intervals from October, 1974 through October, 1975. Seasonal changes were observed for serum LH, testosterone and libido index scores. Mating activity in rams was highest for both breeds during the peak breeding season (October) and declined 50% by late spring and summer before it increased the next October.

Serum LH concentrations were lowest in May (.54 ng/ml) and increased abruptly in July ( …


Availability Of Trypotophan In Some Feedstuffs For Swine, Pedro H. Rivera L., E. R. Peo, Jr., T. Stahly, B. D. Moser, P. J. Cunningham Jan 1976

Availability Of Trypotophan In Some Feedstuffs For Swine, Pedro H. Rivera L., E. R. Peo, Jr., T. Stahly, B. D. Moser, P. J. Cunningham

Department of Animal Science: Faculty Publications

Two experiments were conducted to determine the availability of tryptophan (Try) from corn (NC), opaque-2 corn (OC), milo (M) and freeze dried alfalfa (FDA) when fed to swine. The first experiment consisted of a growth trial involving 96 baby pigs and eight treatments. The basal diet containing .06% Try and 24.5% protein was supplemented with .015%, .030% and .045% L-Try. These four diets were used to establish a standard curve for growth. The other treatments were formed by adding the feedstuffs as the source of Try to the basal diet. Availabilities were determined by comparing growth responses. Try availabilities from …