Search results for "Lactation"

The effects of different milking intervals and milking times per day in jennet milk production

2012

Abstract In their first 150 days of lactation, nine Ragusana jennets were investigated at the ‘Istituto Sperimentale Zootecnico per la Sicilia’ (ISZS) in Palermo, to study the effects of different milking typologies on milk production. The jennets were kept in a paddock and were fed hay ad libitum and concentrate (3.5 kg jennet/day). From post-foaling day 21, every 3 weeks individual milk amounts were recorded, and individual milk samples were collected and analyzed for the main qualitative parameters. The compared theses were: two daily milking times with 6- and 3-h intervals; and two, three and eight daily milking times with 3-h interval. The jennets were manually milked. The foals were s…

The effect of the foaling season on lactation length and milk production of jennets

2011

On the origins of body size dimorphism in primates

1986

Among many explanations concerning the origins of dimorphism in Primates, none has received as little attention as the differences in energy requirements of the two sexes. It is hypothesised that among Primates, a common strategy for overcoming the extra metabolic load of pregnency and lactation experienced by females during the greater part of their adult lifetimes, is for them to reduce their bodyweights relative to those of males. Such a strategy allows the mother plus infant combination to weight approximately as much as the species target weight or slightly less, preserving the balance between the species and the environment.

Comparison of Sulla-hay and Sulla-silage in the lactating ewes and their effects on milk and cheese characteristics

2002

Abstract Two methods of storage of Sulla- and oat-grass (silage or hay) were compared. Forty-six homogeneous lactating ewes, housed indoors, were divided into two groups and after 35 days of diet adjustment, were fed ad libitum twice a day, either Sulla- ( Hedysarum coronarium L.) and oat-hay (control group) or Sulla- and oat-silage in partial substitution of hay (silage group). Both groups were fed with 0.5 kg of commercial concentrate. The dietary treatment started 60 days post-lambing and lasted for 58 days. Every day, the feeding intake for each group was recorded. Individual milk yield was measured weekly and at the same time, milk samples were collected and analysed by Milko-Scan 605.…

Genetic parameters for somatic cell score according to udder infection status in Valle del Belice dairy sheep and impact of imperfect diagnosis of in…

2010

Abstract Background Somatic cell score (SCS) has been promoted as a selection criterion to improve mastitis resistance. However, SCS from healthy and infected animals may be considered as separate traits. Moreover, imperfect sensitivity and specificity could influence animals' classification and impact on estimated variance components. This study was aimed at: (1) estimating the heritability of bacteria negative SCS, bacteria positive SCS, and infection status, (2) estimating phenotypic and genetic correlations between bacteria negative and bacteria positive SCS, and the genetic correlation between bacteria negative SCS and infection status, and (3) evaluating the impact of imperfect diagno…

Nitration of cathepsin D enhances its proteolytic activity during mammary gland remodelling after lactation

2009

Proteomic studies in the mammary gland of control lactating and weaned rats have shown that there is an increased pattern of nitrated proteins during weaning when compared with controls. Here we report the novel finding that cathepsin D is nitrated during weaning. The expression and protein levels of this enzyme are increased after 8 h of litter removal and this up-regulation declines 5 days after weaning. However, there is a marked delay in cathepsin D activity since it does not increase until 2 days post-weaning and remains high thereafter. In order to find out whether nitration of cathepsin D regulates its activity, iNOS (inducible nitric oxide synthase)−/− mice were used. The expression…

Copper, iron, and zinc contents in human milk during the first three months of lactation: A longitudinal study

2000

The aim of the study has been to analyze the evolution of copper, iron, and zinc contents in human milk, from colostrum to the third postpartum month, following a longitudinal design, under specific conditions of sample collection and to apply an analytical procedure previously optimized to reduce any variation outside physiological lactation. The copper, iron, and zinc concentrations in 144 milk samples from 39 healthy puerpera women, were analyzed in five stages by flame atomic absorption spectrometry, following a standardized protocol. Copper presented a gradual decrease from 0.38 mg/L to 0.19 mg/L by the 90th day; the particular analysis from colostrum to transitional milk manifested th…

Variation in somatic cell count, California mastitis test, and electrical conductivity among various fractions of ewe's milk.

1991

Abstract Variation of three estimates of udder inflammation (SCC, California mastitis test, and electrical conductivity) among the foremilk, machine milk, and hand stripping samples were studied. Foremilk and hand stripping milks were taken from each individual teat; machine milk was taken from the entire udder. For this experiment a total of 30 Manchega ewes were subjected to machine milking during the 9th wk of lactation. Samples were taken in duplicate during two milkings on consecutive mornings. Significant differences were observed in the SCC and electrical conductivity, but not in California mastitis test, between foremilk and stripping milk The stripping fraction had higher SCC (70 ±…

Genetic and environmental sources of variation for milk yield traits in Barbaresca siciliana breed

2001

Abstract Multi-trait animal model procedures were used to calculate variance for milk yield traits in the Barbaresca siciliana breed. The recorded data consisted of 14 791 lactations from 6678 ewes distributed among 44 herds from six provinces in Italy. The data-set with pedigree information used for the estimation of genetic parameters and correlation, included 6678 ewes with records, 757 dams, 4 paternal grandams, 28 maternal grandam and 2 maternal great-grandams, all without records, and additionally 301 sires, 3 paternal grandsires, 11 maternal grandsires and 1 maternal great-grandsires. The variables considered in the present study were the milk yield at 100 days (MY-100), 120 days (MY…

Relationship between beta lactoglobulin and subclinical mastitis in Valle del Belice sheep breed

2010

The objective of the following research was to determine the effect of LGB genotypes on subclinical mastitis in Valle del Belice dairy sheep. Ewes were classified as affected or not by subclinical mastitis within a lactation based on i) a positive culture in one of the test-days and ii) more than 750,000 somatic cells. Generalized linear mixed models were fitted to assess the significance of LGB genotypes on MTB and MTC. The LGB genotypes significantly affected MTB (p=0.0387), and showed a tendency on MTC (p=0.1104). Least square means showed that in the analysis for MTB, individuals with genotypes BB and AB had a higher frequency of subclinical mastitis. Moreover, the least square differen…