The influence of crossbreeding and LPL genotype on the yield, composition and quality of goat milk

Cilj ovog istraživanja bio je ispitati utjecaj križanja koza i genotipa LPL na prinos, sastav i kvalitetu kozjeg mlijeka. Istraživanje je provedeno u Litvi na stadu čistih sanskih, anglo-nubijskih i križanaca sanskih i anglo-nubijskih koza (n=37). Križanke sanske i anglo-nubijske koze te sanske koze imaju značajno (P<0,05) više (34,91 % i 16,03 %) prinose mlijeka od anglo-nubijske pasmine koza. U usporedbi s kozama križanih pasmina i sanskim kozama, najveći (P<0,05) udio masti i proteina, kao i najniži (P<0,05) udio laktoze i broj somatskih stanica utvrđeni su za anglo-nubijsku pasminu koza. Najveći prinos mlijeka (P<0,05) utvrđen je u genotipu CC gena LPL (u prosjeku 20,08 % veći nego u genotipu CG i GG) koza. Međutim, mlijeko genotipa CC okarakterizirano je i najnižim (P<0,05) udjelom masti, proteina i uree te najvećim udjelom laktoze u usporedbi s mlijekom genotipa CG. Istraživanje je pokazalo da pasmina i genotip LPL utječu na prinos i sastav kozjeg mlijeka te se čine vrijednim biomarkerima u procesu odabira koza.The aim of this study was to investigate the influence of crossbreeding and the LPL genotype on goat milk yield, composition and quality indicators. This research was carried out in a herd of pure-breed Saanen, Anglo-Nubian, and crossbred Saanen and Anglo-Nubian goats (n=137) in Lithuania. Saanen x Anglo-Nubian crossbred goats and Saanen had a significantly (P<0.05) higher (34.91% and 16.03%, respectively) milk yield compared to Anglo-Nubian goats. The highest (P<0.05) fat and protein and the lowest (P<0.05) lactose percentages and somatic cell count were found in the milk of Anglo-Nubian goats, compared to Saanen x Anglo-Nubian crossbreds and Saanen goats. The highest (P<0.05) milk yield was determined in the CC genotype of the LPL gene (on average 20.08% higher than in the CG and GG genotypes) of goats. However, the milk yield of the CC genotype was characterised (P<0.05) by the lowest fat, protein and milk urea levels, and the highest amount of lactose compared to the milk of the GG genotype. The study showed that breed and LPL genotype affected goat milk yield and composition and appear to be the valuable biomarkers of the goat selection process

Development, productivity and health research of cow udder quarters

Aim of the research: To evaluate the morphological and physiological qualities of cow udder quarters and their relationship to the productivity, milk composition and health. Objectives of the research: 1. To evaluate the morphological indices of the development of cow udder quarters. 2. To carry out a research on the time and speed of milking in cow udder quarters. 3. To evaluate the productivity of udder quarters and the composition of milk. 4. To determine the somatic cell count in milk and to establish the agents of mastitis in cow udder quarters. 5. To evaluate the relationship between the morphological and physiological udder qualities with the productivity and health of cows. For the first time in Lithuania the relationship between the morphological and physiological qualities of black and white cow udder quarters and the productivity, milk composition and health has been established by means of applying statistical modelling. The dependency of the morphological and physiological indices of cow udder quarters from the productivity and health of cows has been established. It shows that it is purposeful to use morphological and physiological indices of cow udder quarters in cow selection. It is especially important when the newest milking systems are installed in the farms of milk producing cattle

Relationship of milking traits and somatic cell count with electrical conductivity of goat milk during different milking phases

The aim of this study was to estimate the relation between milking traits and somatic cell count with electrical conductivity of goat milk during different milking phases. The research was carried out in the herd of Czech White Shorthaired and Saanen goat breeds (n=323) with the help of the electronic milk flow meter LactoCorder®. The milk yield, milking duration, milking flow rate and electrical conductivity of milk in the different phases of milking showed the significant mean differences between the breeds. Almost all (except electrical conductivity during the initial time) investigated indicators of electrical conductivity had a significant positive correlation with SCC. The bimodality of milk flow was determined in 9.69 % of goats and associated with milk yield decrease and SCC increase (P<0.05). The results confirm that the milk flow curve data is a good tool to control milking traits of goats, to predict the prevalence of mastitis and, thus, to improve the health of the udder of goats

Effects of single nucleotide polymorphism markers on the carcass and fattening traits in different pig populations

The objective of this study was to investigate the effect of single nucleotide polymorphisms in 4 different genes: growth hormone (GH), leptin (LEP), growth hormone releasing hormone (GHRH) and myogenic factor 5 (MYF5) on fattening and carcass traits in pigs. The polymorphisms of the porcine genes and their relationships with performance traits were analysed in 143 unrelated pigs, belonging to 5 different breeds (Lithuanian White, old-type Lithuanian White, Large White, Landrace and Yorkshire) and 3 groups of crossbreeds (Large White × Landrace, Yorkshire × Large White, Yorkshire × Pietrain). It was found, that MYF5 polymorphism (Y17154.1: g2200G>C) influenced fattening traits with the highest daily weight gain stated in CC genotype. The most preferable LEP polymorphism (TaqI) (U66254.1: g.1112G>A) was AG genotype with lower age to achieve 100 kg of body weight and average backfat thickness, and higher meatness and weight of ham. It was found that pigs with TT genotype in LEP polymorphism (HinfI) (U66254.1: g.3469T>C) had better carcass properties in comparison to other genotypes. These pigs had also the highest meatness and the lowest average backfat thickness. The preferable GHRH polymorphism (JX435113.1: g.405A>C) genotype was CC with the highest daily weight gain. The most desirable TT genotype of LEP polymorphism (HinfI) (U66254.1: g.3469T>C) was found with the highest frequency in Landrace breed. The highest frequency of the most desirable CC genotype of GHRH gene was found in Yorkshire pig breed. So, from all examined genes LEP and GHRH genes polymorphisms seem to be the most preferable biomarkers of pig selection process

The Association between Charolais Cows’ Age at First Calving, Parity, Breeding Seasonality, and Calf Growing Performance

The objective of this study was to evaluate the impact of cows’ calving ages and newborn calf body weight on the pre-weaning growth rates of calves under the farming conditions of a northeastern European country. The females were purebred Charolais cows that calved between 2019 and 2022. A total of 130 calves (bulls = 76; heifers = 54) were observed during the evaluation. The investigation showed that, based on gender, bulls had a 4.28% higher birth weight than heifers (p p p p p p p p < 0.05)

Association between Milk Electrical Conductivity Biomarkers with Lameness in Dairy Cows

Early identification of lameness at all phases of lactation improves milk yield and reduces the incidence of mastitis in the herd. According to the literature we hypothesized that there are associations of electrical conductivity variables of milk flow with lameness in dairy cows. The aim of this study was to determine if blood cortisol and electrical conductivity in the milk flow phases correlate with each other and whether they are related to cow lameness. On one farm, out of 1500 cows, 64 cows with signs of lameness and 56 healthy cows were selected with an average of 2.8 lactations and 60 days in the postpartum period. A local veterinarian who specializes in hoof care treatments identified and scored lameness. During evening milking, the milk flow of all 120 cows was measured using electronic milk flow meters (Lactocorder®, WMB AG, Balgache, Switzerland). Before each milking, two electronic mobile milk flow meters (Lactocorders) were mounted between the milking apparatus and the milking tube to take measurements. We found that the average cortisol concentration in the blood of the studied cows was significantly correlated with the laminitis score. Results of this study indicate that the number of non-lame cows with a milk electrical conductivity level of <6 mS/cm even reached 90.8–92.3% of animals. Milk electrical conductivity indicators ≥ 6 mS/cm were determined in 17.8–29.0% more animals in the group of lame cows compared to the group of non-lame cows. According to our study, we detected that blood cortisol concentration had the strongest positive correlation with milk electrical conductivity indicators. Cows with a greater lameness score had a higher cortisol content and milk conductivity