Tyrimo problema: Pienininkystei Lietuvoje plėtoti sąlygos yra palankios, pienas žemės ūkio produkcijos struktūroje užima beveik ketvirtadalį, o pieno produktų eksportas sudaro apie penktadalį šalies žemės ūkio ir maisto produktų eksporto. Lietuvoje karvių produktyvumas artimas Lenkijos ir Latvijos karvių produktyvumui, tačiau nuo kitų Europos Sąjungos šalių karvių produktyvumas atsilieka 15 – 20 proc. Todėl norint konkuruoti pasaulinėse rinkose būtina atrasti patikimų būdų gerinti karvių pieno kokybės rodiklius, taip pat didinti primilžį. Darbo tikslas: ištirti melsvadumblio Spirulina Platensis įtaką pieno sudėties rodikliams. Šiam tikslui įgyvendinti keliami tokie darbo uždaviniai: 1. Ištirti Spirulina Platensis papildo vartojimo įtaką primilžiui. 2. Ištirti Spirulina Platensis papildo vartojimo įtaką pieno sudėties rodikliams. 3. Ištirti Spirulina Platensis papildo vartojimo įtaką somatinių ląstelių skaičiui piene. Atlikę bandymą 8-iuose Lietuvos rajonų ūkiuose nustatėme, kad karvių šėrime panaudojus Spirulina Platensis papildą, iš bandomosios grupės karvių per parą primelžta vidutiniškai 2,44 kg arba 14,2 proc., pieno daugiau, nei iš kontrolinės grupės karvių (p<0,05). Vartojant Spirulina Platensis papildą bandomosios karvių grupės pieno riebumas buvo nustatytas vidutiniškai 0,27 proc., mažesnis, nei kontrolinės karvių grupės (p<0,05), tačiau iš bandomosios karvių grupės per parą gaunama 0,07 kg daugiau pieno riebalų. Pieno baltymingumas bandomosios karvių grupės piene... [toliau žr. visą tekstą] / Research problem: The conditions of the dairy development are favorable in Lithuania. The milk production takes up nearly a quarter of the whole agriculture production and the export of dairy products is about one-fifth of the country agricultural and food export. Lithuanian cow productivity is close to the Polish and Latvian cow productivity, but is about 15 – 20 percent lower than in other European Union countries. Therefore, in order to compete in global markets, it is necessary to find ways to improve the quality of milk, as well as to increase the milk yield. Research purpose: To investigate the influence of the blue-green algae (Spirulina platensis) on the milk composition parameters. For this purpose there are the following tasks: 1. Investigationoftheinfluenceof Spirulina platensis onthemilkingyield. 2. Investigationoftheinfluenceof Spirulina platensis onthemilkcompositionparameters. 3. Investigationoftheinfluenceof Spirulina platensis ontheamountofsomaticcellsinmilk. After tests in eight Lithuanian farms, it was found that the use of Spirulina platensis additives in cow feeding increases the average of milk yield of about 2.44 kg or 14.2 percent in compare with the control group (p<0,05). Although the additives of Spirulina platensis reduces the fatness of cow milk of about 0.27 percent, but absolute amount of the milk fat increases of about 0.07 kg pro day. In the similar way, the milk protein in the test group was lower of about 0.14% than in the control groups... [to full text]

Tiriamasis darbas buvo atliktas 2013 metais Lietuvos sveikatos mokslų universiteto Veterinarijos akademijos Gyvulininkystės katedroje. Bandymas buvo atliktas X ūkyje, esančiame Kėdainių rajone. Tyrimui naudota 20 holšteinų veislės karvių ir 20 simentalų x holšteinų F1 kartos mišrūnių. Visi gyvuliai antros laktacijos ir veršiavosi 2013 m. sausio – vasario mėn. Gyvuliai stebėti ir duomenys apie jų produktyvumą registruoti ir vertinti vienerius metus – nuo 2013 m. sausio 1 d. iki 2013 m. gruodžio 31 d. Darbo tikslas – atlikti pieninių simentalų mišrūnių ir holšteinų veislės karvių produkcijos rodiklių ir somatinių ląstelių skaičiaus piene palyginamąją analizę laktacijos eigoje. Uždaviniai: 1. Įvertinti ir palyginti pieninių simentalų mišrūnių ir holšteinų veislės karvių pieno sudėties rodiklius: primelžto pieno kiekį, baltymų, riebalų, laktozės ir urėjos kiekius piene. 2. Įvertinti ir palyginti somatinių ląstelių skaičių piene tarp pieninių simentalų mišrūnių ir holšteinų veislių karvių. 3. Palyginti abiejų veislių parduodamo pieno ekonominius rodiklius. 4. Palyginti pieninių simentalų mišrūnių ir holšteinų veislės karvių mėsos produktyvumo kokybinius ir kiekybinius rodiklius (parduodamų karvių gyvą svorį ir mėsos išeigą), taip pat atlikti abiejų veislių, ekonominį parduodamos mėsos vertinimą. Tyrimo metu nustatyta, kad vidutiniai primilžiai (simentalų mišrūnių – 8951,0 litrų, holšteinų – 8665,7 litrų) metų laikotarpyje buvo panašūs tarp abiejų veislių, tačiau pieninių... [toliau žr. visą tekstą] / Research was done in the Department of Animal Husbandry in the Veterinary Academy of the Lithuanian University of Health Sciences in the year 2013. Experiment was done in the X farm, located in Kedainiai region, Josvainiai district. 20 holstein cows and 20 simmental-holstein F1 generation hybrids were used for the research. All livestock was from the second lactation and were calving in November-December 2012. Livestock was observed and productivity data was registered and evaluated for one year: from 1st of January till 31st of December in 2013. Objective of the research – to perform comparable analysis of dairy simmental hybrids and holstein cows’ milk production composition and quality rate during lactation. Tasks: 1. To compare milk-producing simmental hybrids and holstein cows’ milk production productivity‘s quality and quantity rates: amount of milk yield, milk proteins, fats, lactose amount, number of somatic cells in the milk, amount of urea. 2. To compare milk-producing simmental hybrids and holstein cows’ meat productivity quality and quantity rates: meat weight and carcase mass. 3. To calculate financial rates of milk-producing simmental hybrids and holstein cows’ meat and milk. During the research it was stated that yield (simmental hybrids: 8951.0 l., holstein: 8665.7 l.) during the year was similar in both stocks (no essential differences have been found), but average annual amount of milk fat (0.32 percent unit) and protein (0,2 percent unit) in simmental... [to full text]

Milk contains high concentrations of calcium. It occurs in two forms, a free ionic form, and calcium associated with milk proteins (caseins). The latter association is called colloidal calcium phosphate. New Zealand Dairy Foods of Takanini is marketing a range of commercial milks in supermarkets. The company uses ultra filtration to concentrate milk proteins and calcium in different milk products. During ultra filtration, the fraction that is retained by the membrane is rich in calcium bound to proteins and the portion that passes through the membrane is richer in the free ionic form. The company wanted to develop a quick and an economical method that can be applied in industrial settings to determine calcium in both these fractions and in other milk products. This research aimed to develop a quick, wet chemistry method to measure calcium in milk fractions and to trial it in an industrial environment. Two methods, the so-called EDTA method and the atomic absorption spectrophotometric method (AA) were trialled as potential reference methods against which to compare results obtained by the method to be developed. The AA method was chosen due to its ease, accuracy and precision. (This could not be selected as the industrial method for a number of reasons.) A colorimetric method was favoured over other contenders. Two colorimetric dyes, Arsenazo I and o-cresolphthalein-complexone (CPC) were chosen to work with. Arsenazo I forms a purple complex with calcium in a suitable buffer at a range of pHs. o-Cresolphthalein-complexone also forms purple-coloured complexes at alkaline pHs. During method development with Arsenazo I, different buffers were trialled and a NaOH/ KCl buffer was selected for further development at pH 12. The method worked well during the development phase but with some inconsistent results at times. o-Cresolphthalein-complexone formed clear purple complexes with Clark and Lubs and 2-amino-2-methylpropanol (AMP) buffers. The key advantage of the CPC dye with AMP buffer was that when 8-hydroxyquinoline was included in the reaction mixture, it successfully masked coloured complex formation due to CPC with magnesium, which is present in milk at about 1/3 the calcium concentration. This effect did not work with Arsenazo I. However, the results obtained with the CPC method were lower than claimed values of most milks trialled during development. Both methods were compared for their precision and it was found that CPC method has better precision and was chosen for further development. To improve the accuracy and precision, various denaturing reagents were used to (hypothetically) release calcium from the caseins. Trichloroacetic acid at 25 % was more effective than the several other denaturing treatments tested. The finalised CPC method, using trichloroacetic acid, AMP and 8-hydroxyquinoline, was then used to monitor calcium concentration over four months in three milk products, skim, Xtra (retentate) and permeate. For all milks, the CPC values were lower than the AA reference values, and the values reported by a commercial analytical laboratory. The reasons for this are discussed, as are other changes in calcium concentration in the three milks throughout the trial. The correlation between the CPC and AA values was poor for Xtra, better for skim, and best for permeate. A chemical model to explain this is discussed. The method developed is cheap and quick, and sample and reagent preparation is simple. The method could be applied in an industrial environment, but a proportionality factor would have to be applied to account for the difference in mean values between the CPC and AA methods.

Milk contains high concentrations of calcium. It occurs in two forms, a free ionic form, and calcium associated with milk proteins (caseins). The latter association is called colloidal calcium phosphate. New Zealand Dairy Foods of Takanini is marketing a range of commercial milks in supermarkets. The company uses ultra filtration to concentrate milk proteins and calcium in different milk products. During ultra filtration, the fraction that is retained by the membrane is rich in calcium bound to proteins and the portion that passes through the membrane is richer in the free ionic form. The company wanted to develop a quick and an economical method that can be applied in industrial settings to determine calcium in both these fractions and in other milk products. This research aimed to develop a quick, wet chemistry method to measure calcium in milk fractions and to trial it in an industrial environment. Two methods, the so-called EDTA method and the atomic absorption spectrophotometric method (AA) were trialled as potential reference methods against which to compare results obtained by the method to be developed. The AA method was chosen due to its ease, accuracy and precision. (This could not be selected as the industrial method for a number of reasons.) A colorimetric method was favoured over other contenders. Two colorimetric dyes, Arsenazo I and o-cresolphthalein-complexone (CPC) were chosen to work with. Arsenazo I forms a purple complex with calcium in a suitable buffer at a range of pHs. o-Cresolphthalein-complexone also forms purple-coloured complexes at alkaline pHs. During method development with Arsenazo I, different buffers were trialled and a NaOH/ KCl buffer was selected for further development at pH 12. The method worked well during the development phase but with some inconsistent results at times. o-Cresolphthalein-complexone formed clear purple complexes with Clark and Lubs and 2-amino-2-methylpropanol (AMP) buffers. The key advantage of the CPC dye with AMP buffer was that when 8-hydroxyquinoline was included in the reaction mixture, it successfully masked coloured complex formation due to CPC with magnesium, which is present in milk at about 1/3 the calcium concentration. This effect did not work with Arsenazo I. However, the results obtained with the CPC method were lower than claimed values of most milks trialled during development. Both methods were compared for their precision and it was found that CPC method has better precision and was chosen for further development. To improve the accuracy and precision, various denaturing reagents were used to (hypothetically) release calcium from the caseins. Trichloroacetic acid at 25 % was more effective than the several other denaturing treatments tested. The finalised CPC method, using trichloroacetic acid, AMP and 8-hydroxyquinoline, was then used to monitor calcium concentration over four months in three milk products, skim, Xtra (retentate) and permeate. For all milks, the CPC values were lower than the AA reference values, and the values reported by a commercial analytical laboratory. The reasons for this are discussed, as are other changes in calcium concentration in the three milks throughout the trial. The correlation between the CPC and AA values was poor for Xtra, better for skim, and best for permeate. A chemical model to explain this is discussed. The method developed is cheap and quick, and sample and reagent preparation is simple. The method could be applied in an industrial environment, but a proportionality factor would have to be applied to account for the difference in mean values between the CPC and AA methods.

[Truncated abstract] Previous studies suggest that the milk of the quokka (Setonix brachyurus) could change composition coincident with critical stages of development of the young, and that the milk energy provided by the mother and its utilisation by the joey would determine the young’s growth rate. To test this general hypothesis, quokkas (n = 19) were bred in captivity and milk was collected during lactation. The samples were analysed using specific biochemical assays and sensitive analytical techniques to determine the composition of the milk of the quokka. The stable isotope, deuterium oxide, was employed to estimate the volume of milk consumed by the joeys. The adult females and their young were weighed and body measurements taken periodically, in order to calculate the body condition of the adults and monitor the growth rate of the offspring. Marsupial lactation can be divided in three phases. Phase 1 of lactation covers the period during pregnancy. Phase 2a of lactation in the quokka (0 to 70 days post partum), is the period when the young is permanently attached to the teat, while Phase 2b (70 to 180 days post partum) is when the joey suckles intermittently but is still confined to the pouch. Phase 3 of lactation extends from the time when the young initially emerges from the pouch to the end of lactation (180 to 300 days post partum) ... The metabolism of fatty acids in quokkas appears to be a combination of the processes in monogastric and ruminant mammals. The growth rate of the young quokkas was dependent on the volume and energy content of the milk consumed. The crude growth efficiency indicates that quokkas are equally efficient as other marsupials reported in the literature, in converting milk energy to body mass. It seems that female quokkas maintained energy balance during lactation, most probably by increasing their food intake rather than mobilising body fat stores. In addition, it appears that quokkas are capable of producing young of similar mass, irrespective of their own body weight or condition, when they have access to an adequate supply of food and water. This was the first study to provide detailed information about milk composition and lactational energetics in the quokka. While the results supported the unifying hypothesis in relation to the major changes associated with the transition through the phases of lactation, wide variations were detected between the quokka and other marsupial species in the changes in the detailed composition of milk and milk production.

[Truncated abstract] Mothers who deliver prematurely often have a delay in lactogenesis II and subsequent milk supply. Furthermore, due to the inability of their babies to breastfeed immediately after birth, these mothers are 'pump dependent' during both initiation and establishment of lactation. Apparently, there are no evidence based guidelines for the expression regime but some data suggesting that expression regimes for both breasts should be at least five times per day and at least 100 minutes expressing time per day. The project was set out to document the self selected current expression regimes of the preterm mothers from day 10 to 60 postpartum. It defined how various aspects of breast expression, such as frequency and interval, impact on the synthesis and production of milk. In addition, it determined the variations in the composition of preterm mother's milk. The collection of 24hr expression data and milk samples at each expression of each breast, each day, of 25 preterm mothers (<32 gestation age) from the neonatal intensive care unit in King Edward Memorial Hospital, Western Australia on day 10, 15-20, 30, 40, 50 and 60 postpartum showed that during the 'pump dependent' period (day 10 20), the frequency of expression for both breasts was 6, 6-7, 3-9 times per day (median, IQR, range) and total duration with the pump was 115, 80-160, 32-320 minute per day (median, IQR, range). Furthermore, during the 'transition from exclusively expressing to exclusively breastfeeding' period (day 30-60), frequency of expression/breastfeed and total duration of milk removal (both expressing and breastfeeding) for both breasts were 6, 5-7, 1-9 and 135, 75-170, 25-320, respectively (median, IQR, range). ... These nutrients make up the energy content of milk, thus the energy content of milk also varied greatly between mothers. Therefore, milk from individual preterm mothers varies greatly for individual values for fat, total protein, lactose and energy and this should be taken into account when calculating the level of fortification required for individual babies. The results suggest that when fortifying mother's milk, weekly measurement of fat and protein in milk would provide good estimates on which to base fortification requirements. The concentration of sIgA plus lactoferrin formed 32% of the total proteins in breastmilk. However there was large variations in the concentration of sIgA and lactoferrin (median, IQR, range: 0.82, 0.59-1.13, 0.05-2.93g/l and 2.41, 1.52-3.52, 0.04-8.82g/l, respectively) between mothers. Therefore the level of protection provided by these two proteins could differ greatly between babies. Further research on the relationship between the concentration of sIgA and lactoferrin in milk and the onset of infection would indicate the minimum amount of these proteins needed for the babies to benefit from the immune protection provided by their mother's milk. The hourly breast expression method and regression analysis of actual milk yield and interval since previous expression provides information that identifies the potential milk synthesis capacity of the breasts of the mothers and the impact of the interval between expressions on the milk production of the mothers. This information can be applied to individualize the interval between expression regimes to optimise milk production and minimize the demand on the mother. In addition, determining the changes in the milk composition of individual mothers would provide a more precise base to fortify their milk for their preterm babies.

The aim of thesis was to analyze results of raw bulk milk according to these quality indicators: fat content, protein content, urea content, casein content, solids-not-fat (SNF) content, lactose content and freezing point. Data were evaluated from November 2009 through October 2010 at two breedings. Limits given by European Union and czech legislation were keep in both breedings. In first breeding were mediumly means 4,127 g/100g fat, 3,427 g/100g protein, 2,601 mmol/l urea, 2,688 g/100g casein, 9,015 g/100g solids-not-fat, 4,887 g/100g lactose and freezing point -0,5265 °C.In second breeding were mediumly means 4,045 g/100g fat, 3,319 g/100g protein, 2,462 mmol/l urea, 2,603 g/100g casein, , 8,839 g/100g solids-not-fat, 4,828 g/100g lactose and freezing point -0,5246 °C. Results were compared and causes of difference and milk quality variation were explained.

The aim of this work was to evaluate the quality of raw cow's milk during the year depending on the breed. In two agricultural companies, respectively in three farms there were monitored total bacteria count (TBC), somatic cell count (SCC), residues of inhibitory substances (RIS), freezing point, protein content and fat content in 2015. Limits of TBC given by European Union (100,000/ml) were kept in all farms. Limits set for SCC (400,000/ml) were exceeded in 25% samples in breeding I and the average value was significantly increased (p <0.001) in comparison to breeding II and III. These results suggest a possible occurrence of subclinical mastitis. For the company it means a significant economic loss. RIS has not been found in any sample. Average protein content of monitored breeding was not too different (3.69; 3.70; 3.67%). Fat content in breeding I (3.84%) was statistically significantly decreased (p <0.001) in comparison to breeding II and III (4.18 4.12%).

Objetivou-se verificar a relação entre a contagem de células somáticas do leite bovino ordenhado separadamente de quartos mamários com a qualidade físico-química do leite, em especial com o leite instável não ácido (LINA). Foram utilizadas 21 vacas das raças Holandês e Jersey, sendo selecionados a partir do teste do CMT os animais que apresentaram pelo menos um quarto mamário normal e os demais quartos com mastite subclínica. Realizou-se análise microbiológica, identificação dos agentes e, durante quatro dias consecutivos, as vacas foram ordenhadas com uma ordenhadeira especial de quartos individuais avaliando a produção, composição química, contagem de células somáticas (CCS) e análise física do leite. O principal agente isolado no leite foi o Corynebacterium sp. (27,38%). Ocorreu diminuição de 21,65% na produção de leite dos quartos com CCS acima de 750.000cél/mL. A instabilidade do leite não apresentou variação significativa dos quartos saudáveis em comparação com os quartos mastíticos. Dentre os componentes químicos do leite, o teor de lactose diminuiu à medida que ocorreu o aumento da CCS e não houve variação significativa nos teores de gordura, proteína bruta, sólidos totais e sólidos desengordurados. Houve variação significativa dos componentes do leite nas diferentes raças. Não houve relação entre a mastite subclínica e o LINA. / This study assessed the relationship between milk somatic cell count from different mammary quarters of cows with subclinical mastitis with physical and chemical milk quality, especially unestable non acid milk (UNAM). Twenty-one Holstein and Jersey cows were used which had at least one healthy quarter and the others with subclinical mastitis. Microbiological analysis was performed and the agents were identified. Cows were milked with a special milking machine which separate milk from each quarter for four consecutive days. Milk samples were collected to evaluate production, chemical composition, somatic cell count (SCC) and physical characteristics. The main agent identified in the milk was Corynebacterium sp. (27,38%). There was a decrease of 21,65% in quarter milk production of cows with SCC above 750.000cél/mL. Milk instability did not vary significantly from healthy quarters compared with mastitis. Among milk chemical components, lactose decreased as the SCC increased and there were no significant variation in levels of fat, protein, total solids and non-fat solids. There were significant variations in the components of milk in different breeds. There was no relationship between subclinical mastitis and UNAM.

O experimento foi conduzido no Sistema de Pecuária de Leite (SISPEL), na Embrapa, em Pelotas, Rio Grande do Sul, com 32 vacas em lactação da raça Jersey em lactação, divididas em quatro grupos, de acordo com a produção de leite, peso vivo, escore corporal e tempo de lactação. O estudo teve o objetivo de avaliar o efeito da suplementação de diferentes fontes e níveis de selênio (Se) em vacas em lactação, sobre as características físicoquímicas do leite, produção de leite e concentração desse no sangue e leite, assim como verificar a ocorrência do leite instável não ácido (LINA) e as alterações na composição do leite e sangue decorrentes da instabilidade. Os tratamentos foram determinados como: grupo controle (dieta padrão), Selênio Inorgânico 0,3 (dieta padrão + 0,3mg Selenito de sódio/kg de concentrado), Selênio Orgânico 0,3 (dieta padrão + 0,3 mg Selêniometionina/kg de concentrado) e Selênio Orgânico 0,6 (dieta padrão + 0,6 mg selêniometionina/kg de concentrado). No leite, foram analisadas composição química, características físicas, contagem de células somáticas (CCS) e teores de Se, cálcio iônico e uréia e, no sangue, albumina, uréia, triglicerídeos, colesterol, glicose, proteína total, Ca, Mg, P e Se. A suplementação de selênio aumentou linearmente a concentração do mineral no leite e no sangue, independente da fonte. Porém, não ocorreram alterações expressivas nas características físico-químicas, CCS e produção de leite relacionada com a suplementação. Das 124 amostras de leite analisadas durante o experimento, 101 (81,45%) foram estáveis e 23 (18,55%) precipitaram em concentrações de etanol até 72%. O leite classificado como leite instável não ácido (LINA) apresentou maior concentração de cálcio iônico e menor concentração de lactose que o leite normal. O sangue de animais que produziram LINA apresentou maior concentração de uréia e triglicerídeos. / The trial was lead in the intensive system of milk production - SISPEL, at the Embrapa, in Pelotas, Rio Grande do Sul State, with 32 lactating Jersey cows, distributed in four groups, according to milk production, body weight, body condition score and days in milking. The study had the objective to evaluate the effect of the supplementation with different sources and levels of selenium (Se) for dairy cows, on the physical-chemical characteristics of milk, milk yield and selenium concentration in the blood and milk, as well as, to verify the occurrence of not acid unstable milk (LINA) and the alterations in the composition of milk and blood. The treatments were denominated as follows: control (diet without added selenium), Inorganic Selenium (standard diet + 0,3 mg sodium Selenite /kg concentrate), Organic Selenium 0,3 (standard diet + 0,3 mg Selenomethionine/kg concentrate) and Organic Selenium 0,6 (diet standard diet + 0,6 mg selenomethionine/ kg concentrate). Physical-chemical characteristics, somatic cells count (SCC), concentration of Se, ionic calcium and urea in milk and albumen, urea, triglycerides, cholesterol, glucose, total protein, Ca, Mg, P in blood had been analyzed. Supplementation of selenium increased linearly the concentration of the Se in milk and blood, independently of the source. There were not expressive alterations for physical and chemical characteristics, SCC and milk yield related to supplementation. Of the 124 analyzed milk samples during the experiment, 101 (81,45%) were stable and 23(18,55%) precipitated in alcoholic solutions wirth ethanol concentrations to 72%. Milk samples classified as not acid unstable milk (LINA) presented greater concentration of ionic calcium and lower concentration of lactose that stable milk. The blood of animals that had produced LINA presented greater concentration of lactosis and triglycerides.