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Development And Evaluation Of The Introduction Of Gramineae In Cuba, R Hernandez, R Machado, J Menendez Jul 2026

Development And Evaluation Of The Introduction Of Gramineae In Cuba, R Hernandez, R Machado, J Menendez

IGC Proceedings (1977-2023)

Cuba has a great endemism in its flora, and more than 400 grass species, but not prominent native plants for animal feeding in extensive production conditions. Pasture introduction started in Cuba more than 300 years ago and has been used to improve grasslands, but it was only since 1962 that an organized intro­duction programme has been carried out. In accordance with this programme, more than 2,000 accessions have been introduced, in­cluding 470 grasses. Australia is the country that has supplied most of these introductions, Africa, Asia and America being the continents in which the most outstanding introductions were originated. The …


Grain Supplements For Breeding Ewes In Continuous Grazing Systems, William G. Allden Jul 2026

Grain Supplements For Breeding Ewes In Continuous Grazing Systems, William G. Allden

IGC Proceedings (1977-2023)

Two suppleme.ntary feeding systems were com­pared. When breeding flocks were provided with purchased barley grain during the prelambing and post-lambing periods each year there were significant increases in ewe body weights, lamb weights, lamb production/unit area, and the amount of pasture present. However, when the grain had to be provided from the grazing area there was no suggestion of any advantage in substituting a barley crop for an area of pasture. These contrasting results indicate that the assessment of animal production systems based on the integration of pasture grazing and grain supplementation should take into account the source of grain …


Forage-Animal Systems For Economic Calf Production, R E. Blaser, R C. Hammes Jr, J P. Fontenot, H T. Bryant Jul 2026

Forage-Animal Systems For Economic Calf Production, R E. Blaser, R C. Hammes Jr, J P. Fontenot, H T. Bryant

IGC Proceedings (1977-2023)

Nine forage-cow-calf systems with constant ,stocking but variable grazing pressures to pro­vide for changing nutritional needs of beef cows, and continuous high calf nutrition with creep grazing gave similar high weaning weights of autumn and winter calves for all-year grazing vs. hay feeding and for 2 stocking rates. The all-fescue systems lowered calf weights. Nine forage-cow-calf systems with constant ,stocking but variable grazing pressures to pro­vide for changing nutritional needs of beef cows, and continuous high calf nutrition with creep grazing gave similar high weaning weights of autumn and winter calves for all-year grazing vs. hay feeding and for 2 …


Energy And Nitrogen Metabolisms Of Steers Fed With Coast Cross No. L Bermuda Gniss (Cynodon Dactylon) Or Pangola Grass (Digitaria Decumbens Stent.) Forages, C M. Geerken, A Diaz, R Gonzalez Jul 2026

Energy And Nitrogen Metabolisms Of Steers Fed With Coast Cross No. L Bermuda Gniss (Cynodon Dactylon) Or Pangola Grass (Digitaria Decumbens Stent.) Forages, C M. Geerken, A Diaz, R Gonzalez

IGC Proceedings (1977-2023)

Two groups of 5 crossbred Holstein calves with 80􀂰 120 kg live weight were used to study the effect of feeding with Coast Cross bermuda grass (Cynodon dactylon) or pangola grass (Digitaria decumbens Stent.) on the energy and nitrogen balance of the animals during the dry and rainy seasons. Bermuda grass had nearly twice the crude protein content of pangola grass in both seasons (8.3 vs. 5.0% DM basis). Balance data obtained for bermuda and pan­gola grasses during the dry season were: intake of DM 3.28 and 3.00 kg/day, metabolizable energy 7.44 and 5.30 Meal ME/day, nitrogen 43.8 and 22.3 …


Effect Of Different Levels Of Protein Supplementation To Steers Grazing Pangola Grass (Digitaria Decumbens Stent.) In The Dry Season, A Delgado, A Elias, J L. Veitia, R Dieguez Jul 2026

Effect Of Different Levels Of Protein Supplementation To Steers Grazing Pangola Grass (Digitaria Decumbens Stent.) In The Dry Season, A Delgado, A Elias, J L. Veitia, R Dieguez

IGC Proceedings (1977-2023)

Ninety crossbred steers(¼ Holstein x ¼ Zebu) of approximately 100 kg live weight were used in a randomized block design with 3 replica­tions to study the effect of protein supplemen­tation to pastures. The levels were: 0, 200, 300, 400, 500, and 600 g ofN x 6.25/animal/day. The experiment was carried out during two succes­sive dry periods. Stocking rates of 5 animals/ha were maintained for each treatment, and each area was divided in 4 paddocks for rotation. The protein supplement had a PN: NPN ratio of60:40. During the first dry period the animals in the control treatment gained 100 g/day and …


Comparison Between Coast Cross No. 1 Bermuda ( Cynodon Dactylon L.) And Pangola (Digitaria Decumbens Stent.) Grasses For Milk Production, Irma Jerez, D Herrera Jul 2026

Comparison Between Coast Cross No. 1 Bermuda ( Cynodon Dactylon L.) And Pangola (Digitaria Decumbens Stent.) Grasses For Milk Production, Irma Jerez, D Herrera

IGC Proceedings (1977-2023)

Twelve crossbred cows in their 2nd and 3rd lactations, 120 days after calving, were used in a switch􀃈back design to compare Coast Cross No. l bermuda (Cynodon dactylon L.) and pangola (Digitaria decumbens Stent.) grasses as sole feed for milk production. Pasture avail­ability was determined b


Evaluation Of Quality Factors In Warm Season Forages, Warren G. Monson, Glenn W. Burton, Wayne W. Hanna Jul 2026

Evaluation Of Quality Factors In Warm Season Forages, Warren G. Monson, Glenn W. Burton, Wayne W. Hanna

IGC Proceedings (1977-2023)

Improved forage quality is a feasible objective. Coastcross-1 bermudagrass, Cynodon dactylon (L.) Pers., selected for high dry matter digesti­bility, has consistently enhanced the perform­ance of the animals consuming it. Variation in quality factors of other species, particularly Paspalum notatum var. Saurae Parodi and Pennisetum americanum (L.) K. Schum., makes it possible to improve digestibility. Pearl millet varieties with improved animal­production potential have been developed and released for farmer use. The varieties have

been selected for higher digestibility and short stature, with reduced stem fractions. The assessment of the digestion of fresh forage permits evaluation of the effects of other factors, …


Estimating The Digestibility Of Herbage By Means Of An In Vitro Technique Based On Cellulase, Kurt Nehring Jul 2026

Estimating The Digestibility Of Herbage By Means Of An In Vitro Technique Based On Cellulase, Kurt Nehring

IGC Proceedings (1977-2023)

A rapid method based on cellulase was devised to estimate the digestibility of feeds. The method is easily applicable and readily reproducible; the standard error of the values is small. The digestibility coefficients established by means of cellulase (DCceBJ were found to be somewhat lower than the in vivo values; the differences go up as the vegetation advances. As the lagging behind of the DC reveals a marked dependence on the crude fibre content, it should be possible to translate to the animal the results obtained by means of the cellulase method. On account of its rapidity and sensibility this …


Forage And Feedstuff Analysis With Infrared Reflectance Spectro/Computer System1, J S. Shenk, K H. Norris, R F. Barnes, G W. Fissel Jul 2026

Forage And Feedstuff Analysis With Infrared Reflectance Spectro/Computer System1, J S. Shenk, K H. Norris, R F. Barnes, G W. Fissel

IGC Proceedings (1977-2023)

An infrared reflectance spectro/computer sys­tem (IRSCS) has been established at The Pennsylvania State University to evaluate the nutritional quality of forage and feedstuffs. Studies with alfalfa forage clearly show that the reflectance spectral curve of the forage is a composite curve consisting of various chemical constituents in the forage such as water, protein and cellulose. Chemical constituents are not measured directly by IRSCS but calibration prediction equations are developed from sam­ples with known chemical constituents and animal response data. After this is completed, forage samples can be analyzed for multiple chemical constituents and animal responses in less than 2 minutes. …


Planning And Balancing Of Feed Requirements And Feed Production According To Standards Of The Energy And Protein Requirements Specified In The Gdr Feed Evalua­Tion System, Arthur Chudy Jul 2026

Planning And Balancing Of Feed Requirements And Feed Production According To Standards Of The Energy And Protein Requirements Specified In The Gdr Feed Evalua­Tion System, Arthur Chudy

IGC Proceedings (1977-2023)

"Feed planning and balancing according to standards of the energy and protein require­ments" has been elaborated as an integral part of the GDR Feed Evaluation System to ensure that feed supply can be planned according to actual requirements, and has, by using com­puter techniques, been introduced in the GDR for planning activities at enterprise level as well as for national planning at territorial levels. The standards characterize the feed require­ments encountered under average production conditions for large livestock populations and longer spans of time. They have been derived for all animal species and production objectives from the requirement standards for …


Roughage Quality Estimation In The Gdr Feed Evaluation System, Bernd Hoffmann Jul 2026

Roughage Quality Estimation In The Gdr Feed Evaluation System, Bernd Hoffmann

IGC Proceedings (1977-2023)

The quality of a feed is defined as the sum of the properties characterizing the feed in terms of its employment for animal production pur­poses. It unites parameters for the energy con­centration, contents of specific nutrients, die­tary characteristics, and properties· affecting feed intake. To facilitate roughage quality esti­mation, feed testing and attestation documents have been elaborated in connection with the introduction of the GDR Feed Evaluation Sys­tem. These documents include attestation tables for determining major feed value parameters (energy concentration, protein concentration, energy digestibility), the classification frames for assessing the roughage according to its content of specific nutrients, dietary chara1:­teristics …


How A Drying Plant Influences Intensification In The Development Of Forage Production Along Industrial Lines, Josef Pohl, Manfred Fechner Jul 2026

How A Drying Plant Influences Intensification In The Development Of Forage Production Along Industrial Lines, Josef Pohl, Manfred Fechner

IGC Proceedings (1977-2023)

Since the opening of the Selbelang drying plant, essential changes have occurred in the roughage patterns of the socialist farms in this territory. This development has been charac­terized by a strong decline in hay production, the latter depending strongly on weather con­ditions and involving heavy losses, in favour of the processing and use of dried green crop. Drying of whole plants and straw pelleting have been introduced. Furthermore, the quality of dried roughage has been essentially improved and winter-feeding rations have been stabilized through the use of high-quality dry feeds. Losses from preservation declined. Applying these measures of intensification it …


The Evaluation Of Roughages Under The Gdr Feed Evalua­Tion System, Reinhard Schiemann Jul 2026

The Evaluation Of Roughages Under The Gdr Feed Evalua­Tion System, Reinhard Schiemann

IGC Proceedings (1977-2023)

The purpose and content of the GDR Feed Evaluation System are discussed in the form of a summary report. The GDR Feed Eval­uation System incorporates, in a form suitable for practical application, the following:

Parameters and methods for the complex evaluation of feeds with particular refer­ence to energy and protein (including amino acids), prepared in the form of detailed feed tables for feeding and planning pur­poses [9, 10];

Parameters and methods for determining daily feed requirements and application rates, in the fonn of energy and nutrient • requirement standards for composing op­timum rations according to animal species and performance (9, …


Problems And Possibilities Of Continuous Forage Production In Arid Subtropical Regions, Horst Patzold Jul 2026

Problems And Possibilities Of Continuous Forage Production In Arid Subtropical Regions, Horst Patzold

IGC Proceedings (1977-2023)

The low animal performance and stocking rate in arid subtropical regions mainly depend on the discontinuity of forage production. In winter-raining steppes of North Africa, the cultivation or sod-seeding of adapted grasses, especially for forage production in the dry season. (summer), is recommended. For the dry savannas of West Africa with summer­raining, proposals are made for three different stages depending on the intensity of land use. They include a better use of grazing areas by transhumance, proposals for a ranching system, especially for meat production, and possibil­ities for milk production by stabling of cattle, including forage production under irrigation.


Optimal Combinations Off Our Large Herbivores For Short Grass Prairie, George M. Van Dyne Jul 2026

Optimal Combinations Off Our Large Herbivores For Short Grass Prairie, George M. Van Dyne

IGC Proceedings (1977-2023)

Diets of four large herbivores grazing together on a shortgrass prairie rangeland were studied. Cattle and bison consumed mainly grasses; sheep and antelope consumed mainly forbs. To maximize forage use, optimal grazing deter­mined by nonlinear programming would be 67, 20, 12, and I% of the forage grazed to be taken by cattle, bison, sheep, and antelope, respectively. Historically, this range has been grazed primarily by cattle. This study suggests more animal production could be attained with a mixture of herbivore species.


Aid To Rangeland Management. Mechanical Type Conversion Of Woodland Areas, William Gordon Leavell Jul 2026

Aid To Rangeland Management. Mechanical Type Conversion Of Woodland Areas, William Gordon Leavell

IGC Proceedings (1977-2023)

Efficient land utilization is essential to meet the growing requirements of an expanding population. The large low-producing pinyon­juniper woodland of the United States offers potential for increased production to meet additional livestock, wildlife, and watershed needs. Through a multiple-use planning pro­cess which determines areas suitable for in­creasing production by mechanical conversion of vegetative types and an environmental anal­ysis procedure which determines the benefits and adverse impacts of such actions, decisions can be made to undertake treatment in an environmentally acceptable manner. The Bureau of Land Management has me­chanically converted over 200,000 hectares of pinyon-juniper to a more diversified and pro­ductive …


How To Organize Feeding In Complex Sheep Production Units In Mountain Areas Of The Kirghiz Ssr, K I. Isakov Jul 2026

How To Organize Feeding In Complex Sheep Production Units In Mountain Areas Of The Kirghiz Ssr, K I. Isakov

IGC Proceedings (1977-2023)

In the Kirghiz SSR, the driving-pasture system is conditioned by the vertical zonation of the Tien Shan and Alai mountain ranges. A fun­damentally new form of livestock production must be practiced to meet the present-day material and technical level of agricultural production. Such a new form is sheep fanning without driving. lt can be introduced in many mountainous regions of the USSR, where "inner" and "outer" pastures are available. The major conditions for a pasture system without driving are the creation of complex sheep production units and the establishment of the necessary fodder base. Two types of sheep production units …


The Biological Performance And Efficient Utilization Of Artificial And Natural Grassland Areas In The Valleys And Mountainous Regions Of The Western Part Of Northern Tien Shan, N I. Zakharev, A A. Atabaev, L A. Golovina, L V. Koverga, N G. Kotysheva, I P. Lazarev, N S. Sotnikova, N N. Sycheva Jul 2026

The Biological Performance And Efficient Utilization Of Artificial And Natural Grassland Areas In The Valleys And Mountainous Regions Of The Western Part Of Northern Tien Shan, N I. Zakharev, A A. Atabaev, L A. Golovina, L V. Koverga, N G. Kotysheva, I P. Lazarev, N S. Sotnikova, N N. Sycheva

IGC Proceedings (1977-2023)

Investigations over several years and numer­ous experiments • carried .. out under different aspects and in different geographical zones revealed the fundamentally new importance of perennial legume/grass mixtures under in­tensive cultivation and utilization. The intensive utilization of young plants in several cuts and cycles at a high level of agrotechnics allows to obtain high yields of best-quality green ma­terial that can be fed fresh or used for pro­ducing feeds of high biological value, especially in regard to the protein, carotene, and phos­phorus contents. Intensive cultivation and utilization of legume/grass mixtures allows by different tech­nologies to produce feeds of high value …


Studies Into Uses Of Natural Nardus Stricta L. Pastures, Totyu Totev, Konstantin Koev Jul 2026

Studies Into Uses Of Natural Nardus Stricta L. Pastures, Totyu Totev, Konstantin Koev

IGC Proceedings (1977-2023)

Experiments were conducted over four con­secutive years, with the view to comparing controlled and unrestricted grazing by sheep. Controlled grazing was found to help increas­ing the green matter yield by 13.3 % and the hay yield by 12.5 %. The actual yield levels resulting from controlled grazing exceeded those ob­tained after unrestricted grazing by 32.5 % for green matter and by 31.5 % for hay. The utili­zation coefficient for green matter was higher by 12.5 %- A controlled grazing regime increased the consumption of real forage plants, such as Agrostis vulgaris, Festuca rubra V. Fallax, and Deschamps1a flexuosa, whereas forb …


Utilization Of Soil In Northern Latitudes, Vasil Ivanovich Ustinov Jul 2026

Utilization Of Soil In Northern Latitudes, Vasil Ivanovich Ustinov

IGC Proceedings (1977-2023)

About half of the territory of the Soviet Union is located in the Far North and in regions with similar conditions, including the vast lands of the tundra and forest tundra as well as the various subzones of the taiga. More than 500 million hectares are considered as forage-bearing land: grazing for reindeer and other farm animals, hay land, and potential arable land. Many scientists believe that up to 5 million head of reindeer may be kept grazing these lands. In recent times, great attention has been paid to the rearing of horses, elks, and musk­oxes in northern latitudes. Measures …


Flood Adaptation And Productivity Of Savanna Grasses, E Gonzalez Jimenez, A Escobar Jul 2026

Flood Adaptation And Productivity Of Savanna Grasses, E Gonzalez Jimenez, A Escobar

IGC Proceedings (1977-2023)

Savannas subjected to seasonal flooding occupy· vast areas of the Tropics. Above-ground bio­mass values for Venezuelan flooded savannas are high and related to the longer availability of water. C3 plants colonized the waterlogged unit and showed the highest productivity and nutritive value. This natural system permits a prolonged grazing season. These first results show the great potential for animal production of this ecosystem, stressing the need for coor­dinated research efforts in order to gain a better understanding of it.


Nitrogen Status Of A Shortgrass Prairie, Pasture Ecosystem, Robert G. Woodmansee, Jerrold L. Dodd, Rudolph A. Bowman, Charles E. Dickinson Jul 2026

Nitrogen Status Of A Shortgrass Prairie, Pasture Ecosystem, Robert G. Woodmansee, Jerrold L. Dodd, Rudolph A. Bowman, Charles E. Dickinson

IGC Proceedings (1977-2023)

Nitrogen was partitioned among soil organic matter, living and dead plant material, micro­organisms, above-ground and below-ground animals, and mineral N in a shortgrass prairie, pasture ecosystem in eastern Colorado, USA Soil organic matter contained the largest amount of N (89.5 %), and dead plant material contained 6.8 % of the total N in the system. Living organisms contained 3.4 % of the N in the ecosystem. Mineral N accounted for 0.2 %. Less than 1.0 % of the N in the system was located above ground. The amount of N im­mobilized in animals was small.


Evaluation Of Quality Factors In Warm Season Forages, Warren G. Monson, Gkenn W. Burton, Wayne W. Hanna Jul 2026

Evaluation Of Quality Factors In Warm Season Forages, Warren G. Monson, Gkenn W. Burton, Wayne W. Hanna

IGC Proceedings (1977-2023)

Improved forage quality is a feasible objective. Coastcross-1 bermudagrass, Cynodon dactylon (L.) Pers., selected for high dry matter digest­ibility, has consistently enhanced the perform­ance of the animals consuming it. Variation in quality factors of other species, particularly Paspalum notatum var. Saurae Parodi and Pennisetum americanum (L.) K. Schum., makes it possible to improve digestibility. Pearl millet varieties with improved animal­production potential have been developed and released for farmer use. The varieties have been selected for higher digestibility and short stature, with reduced stem fractions. The assessment of the digestion of fresh forage permits evaluation of the effects of other factors, …


Study Of The Dynamics Of Flowering, Protein And Fibre Content In Varieties Of Kenaf (Hibiscus Cannabinus) In Cuba, C M. Puentes, A Mujica, A Hernandez Jul 2026

Study Of The Dynamics Of Flowering, Protein And Fibre Content In Varieties Of Kenaf (Hibiscus Cannabinus) In Cuba, C M. Puentes, A Mujica, A Hernandez

IGC Proceedings (1977-2023)

The search of sources of protein for animal feed­ing is a very important task the world over. Grasses are the most important sources for animal feeding in the Tropics, their protein and mineral contents are generally low due, among other causes, to climatic conditions. This aspect is a limiting factor in dairy cows. Kenaf (Hibiscus cannabinus) is a tropical plant with high contents of protein and miner­als. It was observed in fields of kenaf sown for fibre purposes that cattle entering these fields ate the plants with pleasure. The work was aimed at studying the dynam­ics of biological …


Intra-Specific Variation Within Trifoliuni Repens L. In Relation To The Early Spring And Late Autumn Growth Of Upland And Marginal Pastures, John H. Ollerenshaw, Willaim S. Stewart, Raad H. Baker Jul 2026

Intra-Specific Variation Within Trifoliuni Repens L. In Relation To The Early Spring And Late Autumn Growth Of Upland And Marginal Pastures, John H. Ollerenshaw, Willaim S. Stewart, Raad H. Baker

IGC Proceedings (1977-2023)

There is an urgent need for a better under­standing of the biology of white clover (Tri­folium repens L.) to improve grassland produc­tion in temperate and other regions of the world. Cultivars of this legume are required which can compete with and provide atmos­pherically fixed N for associated grasses in late autumn and early spring. Such cultivars would also improve the quality of the animal diet during these periods of the year. We have collected populations of white clover from northern maritime regions, some of which ap­pear to be frost hardy and adapted to growth at low temperatures. These populations …


Grazing Values Of The Boreal Forest And Tundra Regions, William L. Pringle Jul 2026

Grazing Values Of The Boreal Forest And Tundra Regions, William L. Pringle

IGC Proceedings (1977-2023)

Grazing values of the Boreal forest and tundra regions of our world offer a tremendous future potential for the production of red meat. One of the only means we have of efficiently utilizing our northern lands is by grazing animals -that are able to forage over extensive areas. The Boreal forest and tundra biomes of the world occupy about 2. 3 billion ha. This area is equal to 85 % of the total potential arable area of the earth's surface. By far the largest portion occurs in the U.S.S.R. which has 1.2 billion ha of forest and 321 million ha …


The Importance Of Ley Farming For Improving The Forage Basis Of Tropical Africa, V A. Oyenuga Jul 2026

The Importance Of Ley Farming For Improving The Forage Basis Of Tropical Africa, V A. Oyenuga

IGC Proceedings (1977-2023)

The concept and practice of including short­duration pasture mixtures or leys in agricultural rotations, particularly for intensive livestock production, are of recent development in tropical Africa. Although mixed farming -the keeping of animals for farm work, producing farmyard manure for the maintenance of soil fertility, and rearing of dairy cows to produce milk for household use - was first introduced as an organized system of settled farming in Nigeria in 1922, intensive animal husbandry, based on intensively maintained pasture mix­tures, be it on a small or large scale, is still in the process of widespread development in many parts of …


Management Of Arid Pastures, Cyrus M. Mckell, Don D. Dwyer Jul 2026

Management Of Arid Pastures, Cyrus M. Mckell, Don D. Dwyer

IGC Proceedings (1977-2023)

Arid pasture, natural grazing land, or rangeland are synonymous terms used to describe the extensive areas of open, non-cultivated arid lands over which domestic livestock and wildlife roam in search of feed. These lands are characteristically low in productivity and if managed, the level of management is extensive and based on ecological principles. The term rangeland originated in the United States of America and is gradually gaining usage in other countries to differentiate between intensively managed pastures of humid and sub-humid regions, and the open steppes, deserts, shrub­lands and dry non-commercial forested lands which, in addition to grazing, provide non­consumptive …


New Objectives And Modern Methods Of Forage Grass Breeding In The German Democratic Republic, Heinrich Baudis Jul 2026

New Objectives And Modern Methods Of Forage Grass Breeding In The German Democratic Republic, Heinrich Baudis

IGC Proceedings (1977-2023)

The objectives of forage grass breeding in the GDR are derived from the social development processes which, in socialist agriculture, find their expression in further intensification, concentration and spezialization of plant and animal production. New aspects which have been recognized only recently, for example, positive response to intensification measures, suitability for industrialized production me­thods, increased yield stability and improved quality in addition to a higher yielding poten­tial, have the decisive say in the breeding tar­gets. The most important traits and properties from the breeder's point of view are dealt with in detail. Explanations on practical breeding work and on some …


Possibilities Of Dry Matter Production From Forage Plants Under Different Climatic Conditions, Th Alberda Jul 2026

Possibilities Of Dry Matter Production From Forage Plants Under Different Climatic Conditions, Th Alberda

IGC Proceedings (1977-2023)

On the basis of the gross photosynthesis of closed green grass swards the net potential dry herbage production of permanent pastures is calculated for the climatic and soil conditions for the so-called broad soil regions and summa­rized per continent. The values thus obtained form the upper level of dry herbage production to be reached on the prevailing permanent pas­ture area. Subsequently the minimum level of dry herb­age production is calculated, based on data on the production of marketed secondary prod­ucts as meat and milk. Since not all these secondary products are marketed and since not all the herbage produced is …