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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Daugiakomponentinio raciono ir raciono mišinio pieno galvijams palyginamasis įvertinimas / Comparision of effective of conventional ration and total mixed ration (TMR) for dairy cattle

Glinskis, Alvydas 17 March 2008 (has links)
Pienininkystė yra svarbi mūsų krašto gyvulininkystės šaka. Pagal Lietuvos žemės ūkio ir kaimo plėtros strategiją pieninė galvijininkystė pripažinta viena iš prioritetinių žemės ūkio šakų. Mūsų šalyje 2006 metais pieno gamyba sudarė 23 % bendrosios žemės ūkio produkcijos. Pieną bei jo produkciją gamina daugiau nei 180 tūkst. ūkio subjektų. Pastaraisiais metais apie 50 proc. perdirbto pieno yra eksportuojama. Todėl labai svarbu gerinti šios gamybos efektyvumą. 2006 metais iš vienos karvės Lietuvoje vidutiniškai primelžta 4484 kg pieno arba 12 proc. daugiau nei 2002 metais. Nors šalyje vidutinis pieno primilžis iš karvės nuolat didėja, bet kol kas yra vienas mažiausių ES. Pienininkystei plėtoti yra palankios gamtinės sąlygos, šalyje veisiami galvijai gerai prisitaikę prie esamos pašarų bazės, jų genetinis produktyvumas gana aukštas. Tačiau dėl konkurencijos augant reikalavimams šalies ir užsienio rinkose, reikia siekti efektyvesnio pieno ūkio vystymo. Pieno gamyboje daugiau nei 60 proc. išlaidų tenka pašarams. Tod��l jų gamybos kaštai, kokybė ir maistingumas daro didžiausią įtaką pieno gamybos ekonomiškumui. Mažinant pieno gamybos savikainą, labai svarbu pasiekti aukštą pašarų maisto medžiagų konversiją. Efektyviau panaudoti pašarus ir, esant tiems patiems ištekliams, gauti daugiau produkcijos padeda įvairių pašarų paruošimo šėrimui būdų taikymas. Todėl, tobulinant produktyvių karvių šėrimo technologijas, ieškoma naujų, pažangesnių pašarų paruošimo būdų ir vienas iš jų gali būti... [toliau žr. visą tekstą] / Dairy farming has always been a primary important branch of cattle breeding in our country. Dairy farming is considered to be the essential direction of the strategy of agricultural development in the country of Lithuania. Dairy production made 23% of total agricultural production during the year of 2006. Milk and dairy production is produced by more than 180 thousands of agricultural subjects. About 50% of produced milk has been exported recently. It explains why economical efficiency of the production is especially important. Despite the fact that an average milk production per cow has been increasing recently, but it remains among the lowest ones in the EU. During the year of 2006 an average milk production per cow made 4484 kg of milk, 13% more than in 2000. It should be stated that our country is distinguished by quite favorable conditions for dairy farming. The cattle bred in the country are adjusted to the existing forage basis and the potential of their genetic productivity is rather high. Nevertheless, the higher requirements caused by the competition on the inner and foreign market force to seek for the more efficient development of dairy farming. About 60% of expenditure in milk production is spent on forage. That is why costs of forage production, quality and nutritional value mainly determine milk production economy. In order to decrease milk production costs it is primarily important to reach high conversion of forage nutritional substances. For more effective... [to full text]
72

Karvių sėklinimo Šiaulių rajone aktualijos. Pieno gamybos stambiuose rajono ūkiuose ypatumai ir problemos / Topicality of cows semination in Siauliai area. Main problems and peculiarity of milk production in large farms

Mockienė, Ligita 30 June 2008 (has links)
Pieninė galvijininkystė ir toliau išlieka pirmaujančia gyvulininkystės produkcijos gamybos kryptimi, o didėjantys reikalavimai šalies ir užsienio rinkose reikalauja gyvulių produktyvumo ir genetinio potencialo didinimo bei produkcijos kokybės gerinimo. Lietuvos ūkininkų pienininkystės ūkiai yra truputį mažesni nei vidutiniai. Pastaraisiais metais jų skaičius padidėjo, jie stambėjo, o jų veiklos rezultatai gerėjo, nes didėjo pieno kaina, primilžis iš karvės ir valstybės parama. Darbe aprašomos kai kurios galvijų veislės: holšteinai, Švedų žalieji, Danų žalieji, airšyrai, anglerai, švicai, Lietuvos žalieji ir Lietuvos juodmargiai. Taip pat kai kurios bulių linijos, kurių palikuonės yra auginamos mano aprašytuose ūkiuose. Šiame magistriniame darbe analizavau penkių vidutinio stambumo ir stambių Šiaulių rajono pienininkystės ūkių (Vitoldo Norkaus, birutės Plenaitienės, Loretos Gabšienės, Antano Mikaičio, Ligitos Mockienės) reprodukcijos ir produktyvumo duomenis: bandų genealoginė analizė, karvių veislių, linijų aprašymas, karvių sėklinimo ypatumai, atskirų linijų bulių panaudojimo dažnis, sėklinimo rezultatai, ūkių produktyvumo ekonominė analizė. Išanalizavusi šiuos duomenis, įvertinau teigiamus ar neigiamus aspektus, pateikiau siūlymus, kaip spręsti ūkyje esančias problemas suplanavau ir pateikiau ūkininkams sėklinimo planus. / Milk breeding is still the main and advanced tendency in whole breeding production. Because of modern aspect, specifications are used to grow in local and abroad market. This situation demands for more productivity , bigger genetic potential and better quality in production. Lithuanias farmers own dairying farms which are mostly smaller than normal. For the last few years the number of such farms has grown up a bit and the farms which already existed became larger. Because of this progress, situation gives better result – milk price came up, to get more yield is accessible, also helps the State support. In this paper are mentioned such cattle kinds as Hosteins, Swedish Reds, Danish Reds, Airshires, Anglers, Shwics, Lithuanian Reds and Lithuanian Black and Whites. Also are discussed few bull lines, which are cultivated in the farms which i already mentioned. In this graduate paper work i am analysing five normal and large size farms in Siauliai area. Those are farms are owned by farmers: Vitoldas Norkus, Birute Plenaitiene, Loreta Gabsiene, Antanas Mikaitis, Ligita Mockiene. I compared reproduction and production facts such as: herds genealogy schemes, herds line, kinds of cows, semination peculiarity and results, different lines of bulls popuarity, economic condition of each farm productivity. I have examined all these facts, pointed positive and negative aspects as well i made some suggestions how the problems in farms could be solved and made some proposition because... [to full text]
73

Effects of a difficult calving on the subsequent health and welfare of the dairy cows and calves

Barrier, Alice Ce´cile Madeleine January 2012 (has links)
Yearly calvings are essential to the sustainability of modern dairy farming. Currently, calving difficulty (or dystocia) affects one in six calvings among UK dairy herds but vary from 2 to 50% internationally. In dairy cows, despite reports of impaired performance, the extent and threshold of the effect of dystocia on health and performance remains unclear. Over the past years, there has also been increasing concerns about the levels of pain experienced by the dystocial cows. Better understanding of their parturition progress and behaviours is needed so that informed decisions on pain mitigation can be taken. Additionally, the impact of dystocia (besides stillbirth) should also be addressed in dairy calves. The objective of this study was to address the effects of a difficult calving on the health and welfare of both dairy cows and calves. Retrospective analyses of an experimental farm’s detailed records were used to relate calving difficulty with health and performance of the dairy cow. The results showed that after any difficulty at calving, dairy producers incur long-lasting shortfalls in milk sales. Dystocial cows also have impaired fertility, are more likely to leave the herd early and have a higher risk of dystocia at the following calving, thus there is a long-term detrimental impact on dystocial cows. Video monitoring of calvings allowed detailed investigation of the parturition progress and behaviours of dystocial Holstein cows giving birth to singleton liveborn calves. The study of calving behaviours and parturition progress indicated longer later stages of parturition, increased restlessness and tail raising in the six hours preceding expulsion of the calf, for dystocial cows receiving farm assistance compared with cows calving unaided. This may relate to the expression of higher levels of pain when dystocia occurs. The onset of maternal behaviour was not delayed following calving difficulty, and firm conclusions could not be drawn from investigation of some behavioural indicators of pain in the first three hours postpartum. Experimental work allowed the monitoring of a cohort of 496 calves born with various degrees of birth difficulty over two years. All but one vet assisted calves were born dead, and farmer assisted calves were more likely to be stillborn than calves born without assistance. Stillborn dystocial calves displayed larger internal damage, than stillborn eutocial calves, but they did not have a different body shape at birth than dystocial calves that survived. Dystocial dairy calves that survived the birth process had lower vigour at birth, had higher salivary cortisol, acquired lower passive immunity and received more health treatments in the neonatal period. Dystocial heifers also had higher mortality rates by weaning but had similar growth to first service. Historical records from the farm also showed that dystocial heifer calves were three times more likely to have died by weaning and by first service than calves born without assistance. For those who survived, there was, however, no indication of altered growth to weaning or subsequent impaired fertility. This may be explained by the early mortality of the most badly affected calves or by farm management. However, their high mortality rates still raise welfare concerns. Altogether, results suggest that dairy calves born with any difficulty have poorer welfare in the neonatal period and possibly beyond. The experience of any calving difficulty in dairy cattle therefore not only impairs the welfare of the cow, but also the welfare from their resulting calf. Any strategy implemented to lower the occurrence and mitigate the effects of dystocia will therefore improve the welfare of the cows, their calves and enhance the farm’s economic sustainability.
74

Pašarų bazės ir karvių produktyvumo analizė LSMU VA Praktinio mokymo ir bandymų centre / The analysis of feed basis and productivity of cows‘ in the centre of practical training and testing at the Lithuanian University of Health Sciences Veterinary Academy

Milius, Justinas 18 June 2013 (has links)
Darbo tikslas: išanalizuoti LSMU VA Praktinio mokymo ir bandymų centro pašarų, naudojamų melžiamų karvių šėrime, kiekybinius ir kokybinius rodiklius bei racionus ir karvių produktyvumą. Darbo uždaviniai: 1. Nustatyti kiek ir kokių pašarų sukaupta ūkyje melžiamų karvių šėrimui per pastaruosius 2 metus. 2. Išanalizuoti ūkio melžiamų karvių šėrimą ganykliniu ir tvartiniu laikotarpiais. 3. Išanalizuoti karvių produktyvumo ir pieno kokybinius rodiklius. Atlikus analizę buvo nustatyta, kad tirtame ūkyje daugiausiai laikoma Vokietijos juodmargių veislės (~50 proc.) ir Lietuvos juodmargių (~30 proc.) karvių. Daugiausiai bandoje buvo 1 – 3 laktacijų karvių (78,6 - 83,5 proc. visos bandos karvių). Vidutinis karvių produktyvumas 6835 kg pieno 4,23 proc. riebumo, 3,3 proc. baltymingumo; vidutinis somatinių ląstelių skaičius - 287 tūkst./ml. Atlikus melžiamų karvių šėrimui pašarų bazės analizę nustatėme, kad ūkis daugiausiai sukaupė vienmečių žolių siloso (873,9 t). Pašarų kokybės parametrų analizė parodė, kad siloso kokybės parametrų fermentacijos rodiklis kokybė ir stabilumas yra geri. Tyrimų metu išanalizuoti karvių racionai pagal mitybinius rodiklius tiek tvartiniu, tiek ganykliniu laikotarpiu buvo praktiškai panašūs ir orientuoti į 21 l pieno primilžį. Išvados: 1. Tirtame ūkyje melžiamų karvių skaičius padidėjo nuo 145 vnt. 2011m. iki 199 vnt. 2012 m. Bandos analizė pagal karvių veisles parodė, kad daugiausiai laikomų karvių yra Vokietijos juodmargių veislės (apie puse bandos... [toliau žr. visą tekstą] / Aim of paperwork: To analize the feed, used for feeding dairy cows at the LUHS VA Practical training and testing centre and to analyze their quantative and qualitative indicators, rations and productivity of cows. The goals: 1. Determine the amount and type of feed accumulated in the farm for dairy cows feeding in the last 2 years. 2. To analyze the feeding of dairy cows on pasture and indoor feeding periods. 3. To analyze the productivity of cows and milk quality indicators. The analysis showed that the studied farm mainly considered German Black & White (~50 per cent.), and the Lithuanian Black and White (~ 30 percent) cows. Most herds were 1 -3 lactation cows (78.6 to 83.5 percent. entire herd of cows). Average productivity of 6835 kg of cow, milk fat - 4.23 percent., mikk protein - 3.3 per cent. The average somatic cell count - 287 thous./ml. Dairy cows feed database analysis found that the farm mainly accumulated perennial grass silage (873.9 t). Feed quality parameters showed that quality parameters of silage fermentation rate quality and stability is good. Studies to analyze the rations by nutritional indicators both indoor and outdoor period was practically similar and focus on the 21 l milk yield.
75

Influence of nutrition and body composition on milk production in the grazing ewe

Geenty, Kennett Gordon January 1983 (has links)
Two experiments were conducted to examine the interrelationships between body composition at parturition, herbage allowance during lactation and milk production. Detailed measurements of feed intake and changes in body composition allowed estimates of maintenance energy requirement and efficiency of use of energy for milk production. Dorset ewes were offered low (L-) or high (H-) herbage allowances during pregnancy to achieve post-partum body weights, respectively, of about 50 and 60-65 kg. During the first 6 weeks of lactation herbage allowances were approximately 2 (-L), 5 (-M and -Mm) and 8 (-H) kg DM/ewe/d and feed intake was determined using chromic oxide dilution. In the first experiment (Expt.A) ewes were machine-milked and in the second (Expt.B) they were suckled by twin lambs with a further group (-Mm) machine-milked. Samples of ewes were slaughtered during early pregnancy, post-partum, and after 6 weeks of lactation. Body weight differences post-partum between L- and H- groups were 10 and 15 kg in Expts.A and B respectively. During lactation body weight changes appeared erratic, particularly in Expt.B, owing to the effects of variation in gut fill. Daily feed intake of machine-milked ewes on -M and -H allowances reached a maximum (1.9-2.2 kg OM/ewe/d) 2-3 weeks after parturition but ewes rearing lambs on similar allowances showed maximum intake (2.5-2.8 kg OM/ewe/d) during the first week. Mean intakes during lactation were 58, 69 and 73 g DOM/kg W•⁷⁵/d respectively for -L, -M and -H groups machine-milked and 51, 75 and 83 g DOM/kg W•⁷⁵/d respectively for -L, -M and -H groups rearing twin lambs. In both experiments ewes in L- groups had approximately 14% greater mean intake (g DOM/kg W•⁷⁵/d) during lactation compared with those in H- groups. Mean daily milk production of ewes rearing lambs was 2.0, 2.5 and 2.7 kg/d respectively in -L, -M and -H groups and was 33-52% greater than that for machine-milked ewes offered similar herbage allowances. In both experiments L- ewes had 14% greater milk yield (g/kg W•⁷⁵/d) compared with H- ewes. Mean lamb growth rates in Expt.B averaged 209, 254 and 268 g/lamb/d in -L, -M and -H groups, respectively. Lambs in the H- group were approximately 11% heavier at birth than those in the L- group and their mean growth rate was 20 g/d greater. Body fat and energy content of live ewes at the start of lactation was predicted using regression relationships from ewes slaughtered post-partum. There was large variation in the energy content of body weight loss during lactation (-37 to +140 MJ/kg) owing to variation in weight of gut fill and changes in chemical composition of the empty body. In Expt.A the body fat content of ewes during early pregnancy was 16.9 kg. Predicted values post-partum were 10.0 and 15.7 kg in L- and H- groups, respectively. During lactation all groups showed body fat losses which ranged from 53 (LH) to 120 g/d (HL). Body fat content during early pregnancy in Expt.B was slightly greater (19.0 kg) than in Expt.A and predicted values post-partum were 11.5 (L-) and 19.7 kg (H-). Fat mobilization during lactation was greater than in Expt.A, and ranged from 157 (LH) to 287 g/d (HL). In both experiments there were losses in body protein during pregnancy in L- ewes (5 and 15 g/d in Expts.A and B respectively). During lactation, protein losses were most evident in H- ewes, being greatest in HL groups (26 and 43 g/d in Expts.A and B respectively). Water: protein ratio in the empty body showed a progressive increase during pregnancy and lactation in both experiments. Estimated maintenance energy requirement for machine-milked ewes tended to be greater for H- (.236 MJ ME/kg W/d) compared with L- ewes (.205 MJ ME/kg W/d) but was similar for both groups of ewe rearing lambs (average of.238 MJ ME/kg W/d). Efficiency of use of ME above maintenance for milk production (K₁) in L- and H- groups was, respectively, .69 and .95 in machine-milked, and .69 and .64 in suckled ewes. Energy from mobilized body tissues was utilized for milk production with respective efficiencies in L- and H- ewes of .23 and .35 in machine-milked, and .40 and .50 in suckled ewes. Efficiency of conversion of total energy available (i.e. ME above maintenance and mobilized tissue energy) to milk energy (K₁(t)) when compared among all groups in both experiments, tended to decrease (from .84 to .51) with increasing body energy mobilization. There was a positive relationship, however, between K₁(t) and the proportion of mobilized energy derived from body protein. Metabolizable energy intakes in the present experiments appeared to be 10-15% greater than calculated requirements from ARC (1980). Estimates of ME requirements for lactating ewes at pasture, in relation to body weight, level of milk production and body energy change, have been calculated based on the present data.
76

Temperament and milk quality in sheep and cattle

Sart, Sarula January 2005 (has links)
[Truncated abstract] It is well known that cows produce more milk if they are comfortable at milking, because stress from milking may cause them milk ejection problems. Temperament is an intrinsic characteristic of the animals so may affect the level of comfort at milking, and stress from the milking process itself may have a greater impact on animals with nervous temperament than on those of nervous temperament. When the milking becomes a stressor, it may affect secretion of milk ejection hormones that, in turn, may affect milk yield and composition. There is little evidence for how animal temperament affects milk quality in different farm animals. In this thesis, I have examined the effects of temperament on quantity and quality of the milk from Merino ewes and Holstein cows. I also tested whether temperament affected the processing performance (clotting properties) of the milk from Merino ewes. The general hypotheses tested were: 1. Calm ewes would produce more milk of better quality than nervous ewes, and, consequently, the clotting properties would be better in the milk from calm ewes than from nervous ewes. 2. Calm cows would produce more milk of better quality than nervous cows.
77

Driving and restraining forces for economic and technical efficiency in dairy farms : what are the effects of technology and management? /

Hansson, Helena, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.
78

Environmental systems analysis of arable, meat and milk production /

Elmquist, Helena, January 2005 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 4 uppsatser.
79

Factors affecting cow behaviour in a barn equipped with an automatic milking system /

Forsberg, Anne-Mari, January 2008 (has links) (PDF)
Lic.-avh. Uppsala : Sveriges lantbruksuniversitet. / Härtill 2 uppsatser.
80

Suplementação com gordura protegida de óleo de palma na alimentação de vacas leiteiras

Zatta, Marcelo Rodrigo 25 August 2014 (has links)
As vacas leiteiras necessitam logo após o parto ingerir grande quantidade de energia para sustentar a síntese de leite que aumenta linearmente. Com isso o objetivo do trabalho foi avaliar o efeito dos níveis de óleo de palma na forma protegida como suplemento na alimentação de vacas leiteiras, sobre a dinâmica corporal, produção e composição do leite, perfil metabólico e reprodução. O experimento foi conduzido nos meses de julho e agosto de 2013 no município de Chopinzinho –Paraná, foram utilizadas 27 vacas da raça Holandesa com peso médio de 651 ±82,7 Kg, distribuídas conforme delineamento em blocos casualizados (DBC) de acordo com a fase de lactação (0 a 90 dias) e três tratamentos de níveis de inclusão de gordura protegida Magnapac® (Madrid, Espanha). Os blocos foram formados a partir da produção média de leite, devidamente equilibrados por peso, idade, número de crias. Os tratamentos constituíram da inclusão de gordura protegida de óleo de palma na proporção de 0, 250 e 500 g/animal/dia. As pesagens de leite e coleta para análise da composição centesimal, bem com as coletas de sangue foram realizadas nos dias 07, 14 e 30 após início da suplementação. Os diagnósticos reprodutivos foram realizados nos dias 0 e 30.Os resultados da produção total de leite não apresentaram efeito significativo (P>0,05) em relação aos diferentes níveis de gordura protegida. Quanto à composição centesimal do leite os parâmetros, gordura, proteína, lactose, extrato seco total, extrato seco desengordurado, ureia e contagem de células somáticas não tiveram efeito significativo (P>0,05). No perfil metabólico as variáveis que apresentaram aumento linear (P<0,05) foram Colesterol Total e Colesterol-LDL as demais variáveis, aspartato amino transferase, gama glutamil transferase, albumina, proteínas totais, uréia, fosfatase alcalina, colesterol hdl e triglicerídeos não foram influenciadas (P>0,05). Em relação a parte reprodutiva a suplementação com gordura promoveu aumento na taxa de prenhez e retorno ao cio nos grupos 250 e 500 gramas, bem como diminui a quantidade de vacas em anestro. A suplementação de gordura protegida de óleo de palma na dieta de vacas leiteiras se mostrou eficiente no aumento dos níveis plasmáticos de colesterol total e colesterol – LDL, promovendo melhorias na reprodução, porém não altera significativamente a produção de leite bem como sua composição. / Dairy cows need to eat right after childbirth lot of energy to support milk synthesis increases linearly. With the objective of this study was to evaluate the effect of levels of palm oil in protected form as a supplement in the diet of dairy cows on body dynamics, production and milk composition, metabolic profile and reproduction. The experiment was conducted in the months of July and August 2013 in the city of Paraná, Chopinzinho, 27 Holstein cows were used with an average weight of 651 ± 82.7 kg, distributed according to a randomized block design (RBD) according to lactation (0-90 days) and three treatments inclusion levels of protected fat Magnapac ® (Madrid, Spain). The blocks were formed from the average milk production, properly balanced for weight, age, number of offspring. The treatments included the Protected fat of palm oil in the proportion of 0, 250 and 500 g / animal / day. The weight of milk and collection for analysis of chemical composition, as well as blood samples were taken on days 07, 14 and 30 after starting supplementation. Reproductive diagnoses were made on days 0 and 30.Os results of total milk production showed no significant effect (P> 0.05) in relation to different levels of protected fat. On proximate composition of milk parameters, fat, protein, lactose, total solids, nonfat dry extract, urea and somatic cell count had no significant effect (P> 0.05). The metabolic profile variables that showed a linear increase (P <0.05) Total Cholesterol and LDL-Cholesterol other variables, aspartate aminotransferase, gamma-glutamyl transferase, albumin, total protein, urea, alkaline phosphatase, HDL cholesterol and triglycerides did not were affected (P> 0.05). Regarding reproductive part supplementation with fat promoted an increase in pregnancy rate and return to estrus in groups 250 and 500 grams, as well as decreases the amount of cows in anestrus. The supplementation of protected fat of palm oil in the diet of dairy cows proved effective in increasing plasma levels of total cholesterol and LDL - cholesterol, promoting improvements in reproduction, but does not significantly alter milk production and its composition. / 5000

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