2 p. / Alfalfa varieties differ in fall dormancy, defined as growth during the fall. Nondormant alfalfa varieties are usually planted in mild winter areas for their ability to grow in the fall. However, fall growth of nondormant alfalfa may be undesirable in areas subject to repeated frosts or freezes. Nondormant, very nondormant, and extremely nondormant alfalfa varieties (fall dormancy class 8, 9, and 10) are adapted to elevations below 4000 feet in Arizona. Other dormancy classes not included in this publication are moderately nondormant varieties (fall dormancy class 7) which may be grown from 3000 to 5000 feet, and semi-dormant and dormant varieties (fall dormancy 6 and below) which are adapted to colder winter areas above 4000 feet.

No description available.

Please read the abstract in the 00front part of this document / Dissertation (MSc (Clinical Epidemiology))--University of Pretoria, 2006. / Clinical Epidemiology / unrestricted

A study was conducted during the period May to September, 1999 to determine the effect of phosphorus (P) supplementation to beef weaners grazing kikuyu (Pennisetum clandestinum) foggage during winter followed by hay towards the end of winter at Dundee in northern KwaZulu-Natal. Foggaging is defined as the practice of allowing herbage to accumulate on a pasture during the growing season (Gertenbach, 1998). This accumulated herbage is then utilized by grazing animals during the dormant season. A total of 200 crossbred beef weaners (average age six months and average weight 175 kg) was used in the trial. Animals were randomly allocated into five groups, each receiving a different supplemental treatment. The treatments were different levels of P supplementation, administered through free-choice P lick supplements, viz. at levels of 0 g P, 2 g P, 4 g P, 6 g P and 8 g P per animal per day. The experiment was divided into two phases. During the first phase (08-06-99 to 20-07-99) the weaners grazed kikuyu foggage and during the second phase (05-08-99 to 16-09-99) they received Smutsfinger(Digitaria eriantha) hay ad libitum. During phase 1 the average weight gain of the animals in Group 1 (receiving 8 g P/animal/day) was significant higher (6 kg/animal during trial) than that of the control group, which received 0 g P/day/animal. Phase 2 which represented a transition from winter to summer showed that Group 1 had an average weight loss of 0.88 kg/animal but the control group lost an average of 5.13 kg/animal. Throughout the trial blood was collected from five animals randomly selected from each group. Plasma inorganic P (Pi) concentrations remained between 1.94 and 2.58 mmol/L. The average trend during phase 1 was that the Pi concentrations increased, while during phase 2, Pi concentrations dropped more (P ¡Ü 0.5) in the animals of Group 1 (8 g P/animal/day) than in the control. This resulted that during the entire experimental period plasma Pi in Group 5 increased while that in Group 1 decreased. Before the animals entered a grazing strip, herbage samples were collected at 14 to 20 day intervals from the five strip grazed kikuyu camps. Samples were divided into leaves and stems which were analysed separately. Mean foggage calcium (Ca) and P concentrations ranged from 25.0 to 29.0 g/kg DM and 20.0 to 27.0 g/kg DM, respectively, while the Ca:P ratios ranged from 1.20:1 to 1.60:1. Calcium concentrations were significantly lower (P = 0.0026) in the stems than in the leaves of the kikuyu foggage, while P concentrations decreased significantly over time, resulting in extremely low foggage P concentrations towards the end of the grazing season. This decrease in P concentrations resulted in Ca:P ratios of above 1:1 instead of the reported ratios of below 1:1 in kikuyu herbage due to low herbage Ca concentrations. The Ca concentrations in the kikuyu in this study were in the same range as herbage concentrations reported in the literature, but P concentrations were much lower than the reported herbage P concentrations. As with the summer pastures we found that magnesium (Mg) concentrations (ranging from 2.1 to 2.6 g/kg DM) were adequate in terms of the requirements of most classes of ruminants. However, potassium (K) concentrations (ranging from 11.4 to 20.3 g/kg DM) were well in excess of animal requirements, and Mg absorption could be severely inhibited by the oversupply of K The sodium (Na) concentration in kikuyu foggage was, as with herbage, inadequate in terms of animal requirements. Zinc (Zn) and manganese (Mn) concentrations were well above animal requirements but below toxic levels. Copper (Cu) concentrations was above animal requirements during May (onset of the study) but decreased significantly to levels below minimum animal requirements. Selenium (Se) concentrations were found to be largely inadequate in terms of animal requirements. The neutral detergent fibre (NDF) levels in kikuyu foggage tended to increase with maturity while acid detergent fibre (ADF) levels did not vary significantly. Crude protein (CP) concentrations decreased as winter progressed to reach levels of < 60 g/kg DM in the dry foggage, indicating that supplementation of CP would be required by animals grazing the kikuyu foggage in mid-winter. It is concluded that if little or no gain is expected from weaners in winter, the Ca and P concentrations in the kikuyu foggage should be adequate. However, if even slight weight gains are required, supplementation of Ca and P would be necessary when the foggage is dry. The P and CP composition of pastures in general were closely correlated and had a seasonal pattern with maximum levels during summer and minimum levels during winter. We can therefore expect that pastures and kikuyu foggage low on protein will also have a P deficiency. In the dry winter we should therefore firstly supplement for protein and energy and then P. The supplementation of P during winter has not only been very positive (in other studies) with positive results on weight gain during the winter period but also during the months thereafter. It is concluded that beef weaners grazing kikuyu foggage in northern KwaZulu-Natal would require supplemental P to maintain their body weights during winter as well as beef weaners on Smutsfinger hay. The recommended level of P supplementation is 8 g P/animal/day. / Dissertation (MSc (Animal Science))--University of Pretoria, 2007. / Animal and Wildlife Sciences / unrestricted

El presente estudio de pre-factibilidad está orientado a la instalación de una planta productora de pellets de heno de alfalfa, localizada en la ciudad de Lima-Perú. Éste estudio es relevante como proyecto de investigación en ingeniería industrial porque integra y relaciona todos los elementos que constituyen un sistema o proceso: personas, tecnología, máquinas, materiales e información, con el fin de optimizar tanto el rendimiento como la calidad de producción del sector industrial de alimentos balanceados para animales pecuarios. Ello permitirá reducir sus costos de producción respetando los factores medioambientales para de un adecuado desarrollo sostenible. / Trabajo de investigación

L’asthme équin est une maladie obstructive récurrente des voies respiratoires. De nombreux facteurs étiologiques ontété déterminés comme pouvant initier ou maintenir l’asthme équin sévère (AES), cependant l’exposition au foin restele facteur de risque principal. L’utilisation de traitements à base de corticoïdes sont efficaces en cas de crise maisinefficaces en l’absence de mesures sanitaires. Ainsi, depuis quelques années un dispositif permettant de « purifier »le foin à la vapeur a été développé, afin de diminuer la teneur en poussières et les antigènes microbiologiques présentsdans le foin. La physiopathologie de l’AES est complexe. Parmi les principaux acteurs de cette réponse immunitaire,les macrophages alvéolaires ont un rôle prédominant dans l’initiation et l’orientation de la réponse immunitaire. Ainsiétudier le rôle des macrophages des chevaux AES permettrait de mieux comprendre l’initiation de la réponseimmunitaire dans l’AES. Dans ce contexte, nous nous sommes interrogés sur l’influence du foin « à la vapeur » surla réponse immunitaire des chevaux AES lors d’un challenge in vivo et lors de la stimulation in vitro des macrophagesalvéolaires. Ainsi nous avons d’abord étudié la réponse systémique et locale des chevaux soumis à un challenged’exposition in vivo à du foin sec ou « à la vapeur ». La première partie de ce travail nous a permis d’observer uneffet bénéfique du foin « à la vapeur » sur le score de mucus trachéal des chevaux CTL et AES cependant nousn’avons pas observé un effet bénéfique significatif du foin « à la vapeur » sur la réponse cytologique et immunitaire.La deuxième partie du travail a permis d’étudier la réponse au foin « à la vapeur » à l’échelle des macrophagesalvéolaires. La microscopie en temps réel a mis en évidence des différences dans le comportement des macrophagesen réponse (1) à différents stimuli, (2) entre les chevaux AES et CTL, (3) entre les HDS provenant de foin sec ou defoin « à la vapeur ». La concentration en IL-1β était significativement plus élevée et la concentration en IL-10significativement plus faible chez les MA des chevaux AES comparés aux chevaux CTL. Une concentration en TNF-α plus élevée après stimulation in vitro a été observée chez les MA des chevaux AES et CTL. Cet état des lieux surla réponse des macrophages alvéolaires stimulés in vivo et in vitro pourra servir de base aux études futures nécessairespour conclure sur le rôle des MA dans le cas de l’AES. Cette triple approche à l’échelle du cheval, du poumon et dela cellule permet une vision globale de la réponse à un challenge d’exposition à du foin sec ou « à la vapeur » etpermet tout de même d’avoir un regard optimiste sur l’utilisation du foin « à la vapeur » pour les chevaux atteintsd’AES. / Equine asthma is a recurrent obstructive disease of respiratory tract. Several aetiologic factors are known to induceor maintain the severe equine asthma (sEA), however the hay exposure is the main risk factor. The use of treatmentswith corticoids are effective in case of crisis, but ineffective in the absence of sanitary measures. So, since severalyears a device allowing to purify the hay with steam was developed, in order to decrease the dust content and themicrobiological antigens within the hay. The pathophysiology of sEA is complex. Among the main actors of thisimmune response, the alveolar macrophages have an important role in the intiatiation and orientation of the immuneresponse. So, investigating the role of the equine alveolar macrophages of sEA horses would allow to betterunderstand the initiation of the immune response in the sEA. In this context, we focused on the influence of steamedhay on the immune response of sEA horses during an in vivo challenge and an in vitro stimulation of the alveolarmacrophages. First, we studied the systematic and local responses of horses submitted to an in vivo challengeexposure to dry and steamed hay. The first part of this work allowed us to show a beneficial effect of the steamedhay on the mucus tracheal score of sEA horses, however we did not observe any beneficial effect of the steamed hayon the cytological and immune response. The second part of the study allowed us to investigate the response of thealveolar macrophages to steamed hay. The real time microscopy showed differences in the behavior of macrophagesin response (1) to various stimuli, (2) between sEA and CTL horses (3) between HDS resulting from dry hay or fromsteamed hay. Moreover, the protein quantification of IL-1β was signifantly higher and the concentration of IL-10significantly lower in AM supernatant of sEA horses compared to CTL. The TNF-α concentration was higher on AMafter in vitro stimulation in sEA and CTL horses. These results on the alveolar macrophages reponse after both invivo challenge and in vitro stimulation, can be used as a basis for future studies in order to further characterize therole of AM in case of sEA. This triple approach on the horse, the lung and the cell scale allows a global vision of theresponse to an exposure challenge to dry or steamed hay and allows having an optimistic preliminary look on the useof the steamed hay for sEA horses.

Water was applied to swaths of cut alfalfa forage with oscillating sprinklers to stimulate rain damage to field drying alfalfa hay to determine the changes in chemical composition, loss of yield, and acceptability of rain damaged hay to sheep. An additional objective was to develop models to estimate yield losses form experimental hay. The experimental hay was prepared with a 2x2x4x4x2 factorial design. The factors were two different cuttings (July and September), two width of swath (3.05 m and 4.27 m), four times of applying artificial rain (3h, 8h, 13h, and 24h after cutting), four levels of artificial rain (no rain, 12.5 mm, 25.0 mm, and 50.0 mm), and two applications of artificial rain (initially and repeated 24h after first application). The hay was dried in favorable weather conditions during the summer season. Fair weather, was observed in the fall season. Chemical composition of the fresh forage at each of the seasons of cutting was closely comparable. Main factors (cut, swath width, time, level, and application of water) and their respective interactions (cut x swath, cut x time, cut x level, time x level) affected chemical composition and voluntary intake of the experimental hay. Samples were analyzed for dry matter, ash, crude protein, plant cell walls, hemicellulose, cellulose, lignin, and acid detergent fiber. No significant changes in the chemical composition occurred when the artificial rain was applied on the fresher forage (<3h after cutting). However, substantial losses were observed after the forage wilted (>13h after cutting). Plant cell contents (100% minus plant cell wall %) decreased while plant cell wall constituents increased with increasing levels of water applied after cutting, and with double application of water. Cell wall content of the hay increased more from rain damage during the fall season than during summer period. Most of the loss of soluble components (cell contents) occurred with the initial application (12.5 mm) of water. Protein content proved to be a poor indicator of rain damage in alfalfa hay. The width of the swather used to harvest the hay (P<.0001), and amount of water applied (P<.0001) were negatively correlated with voluntary intake by lactating ewes. Models for estimating loss of yield from the experimental hay were developed. The amount of rainfall and other descriptive factors were useful to estimate of yield from specific lots of rain damaged alfalfa hay.

This experiment was conducted to determine the effects of corn silage hybrids and nonforage fiber sources (NFFS) in high forage diets formulated with high dietary proportion of alfalfa hay (AH) and corn silage (CS) on ruminal fermentation and productive performance by early lactating dairy cows. Eight multiparous Holstein cows (4 ruminally fistulated) averaging 36 ± 6.2 d in milk were used in a duplicated 4 × 4 Latin square design experiment with a 2 × 2 factorial arrangement of treatments. Cows were fed 1 of 4 dietary treatments during each of the four 21-d periods. Treatments were: 1) conventional corn silage (CCS)-based diet without NFFS, 2) CCS-based diet with NFFS, 3) brown midrib corn silage (BMRCS)-based diet without NFFS, and 4) BMRCS-based diet with NFFS. Diets were isonitrogenous and isocaloric. Sources of NFFS consisted of ground soyhulls and pelleted beet pulp to replace a portion of AH and CS in the diets. In vitro 30-h NDF degradability was greater for BRMCS than CCS (42.3 vs. 31.2%). Neither CS hybrids nor NFFS affected intake of DM and nutrients. Digestibility of N, NDF, and ADF tended to be greater for cows consuming CCS-based diets. Milk yield was not influenced by CS hybrids and NFFS. However, a tendency for an interaction between CS hybrids and NFFS occurred with increasing milk yield due to feeding NFFS with the BMRCS-based diets. Yields of milk fat and 3.5% FCM decreased when feeding the BMRCS-based diet, and there was a tendency for an interaction between CS hybrids and NFFS by further decreased milk fat concentration because of feeding NFFS with BMRCS-based diet. Although feed efficiency (milk/DM intake) was not affected by corn silage hybrids and NFFS, there was an interaction between CS hybrids and NFFS because feed efficiency increased when NFFS was fed only with BMRCS-based diet. Total VFA production and individual molar proportion were not affected by diets. Dietary treatments did not influence ruminal pH profiles except that duration (h/d) of pH < 5.8 decreased when NFFS was fed in CCS-based diet but not in a BMRCS-based diet, causing a tendency for an interaction between CS hybrids and NFFS. Overall measurements in our study reveal that high forage NDF concentration (20% DM on average) may eliminate potentially positive effects of BMRCS. In the high forage diets, NFFS exerted limited effects on productive performance when they replaced AH and CS. Although the high quality AH provided adequate NDF (38.3% DM) for optimal rumen fermentative function, the low NDF concentration of the AH and the overall forage particle size reduced physically effective fiber and milk fat concentration.

Application of fertilizers to soils to increase production yields has raised questions concerning the effect of fertilizer on chemical composition of plants. With the development of accurate, sensitive microbiological methods for the determination of amino acid in protein, speculations concerning amino acid content have been supplanted by acquisition of facts.

A 2 x 3 x 2 factorial arranged split plot experiment was used to determine the decrease of dry matter yield from field-dried alfalfa hay caused by the application of a measured quantity of artificial rain (sprinkling irrigation). The three hay treatment factors were (1) alfalfa hay was cut at late vegetative and early bloom stage of maturity and (2) leached by 0, 5 mm or 20 mm of artificial rain applied by sprinkling and (3) sprinkled in the swath, 24 or 48 hours after cutting. Changes in dry matter yield were not significantly (P<.05) related to stage of maturity of forage, level of artificial rain applied or the time of application of artificial rain. There were no significant interactions for dry matter yield. The non-significant interactions for dry matter yield. The non-significant results were probably due to the variability of the alfalfa stand among the specific areas harvested for each treatment and insufficient replications to control the variability. Forty-eight lambs were fed for 56 days on the twelve experimental hays with four lambs (replications) per treatment. The 56 day feeding period was split into four 14-day pen-type feeding periods. (1, paired feeding in pen; 2, individual feeding in pen; 3, individual feeding in cage; and 4, paired feeding in pen.) There was no significant response of the lamb to alfalfa hay quality (feed intake, weight gain or feed efficiency). Lambs increased feed intake when fed individually compared to pair feeding. The result was increased weight gain and feed efficiency of individually fed lambs. This was particularly evident during period two. There was a significant (P<.05) increase of feed intake associated with advancing maturity of forage during the individual pen feeding period. Feed intake was higher during the second paired pen feeding period relative to the first paired pen feeding, but lower than the single pen feeding. Lambs consumed the rain damaged hay as well as or better than the control hay when fed individually. The also gained faster with the greater feed intake. These results show that sheep will utilize rain leached hay efficiently if it is not heat damaged. The complication of heat damage needs additional study.