38 research outputs found
the influence of pregnancy and the beginning of lactation on pelage traits in cashmere goats
The aim of this study was to investigate the effect of pregnancy followed by the beginning of lactation on fibre traits incashmere goats. Two groups of cashmere-bearing goats aged between 2-3 years were used. The control group (A) included12 non-lactating, non-pregnant subjects. The experimental group (B) included 12 goats mated during the first weekof June, in order to have pregnancy and the beginning of lactation coincide with the period when cashmere normallygrows. As expected, Liveweight significantly varied in Group B during the last two months of pregnancy, when foetalgrowth reaches its maximum, and following delivery. Hair patch weight, because of the continuous growth of primary andsecondary fibres, increased significantly during the trial (P<0.001). The physiological status considered negatively affected(P<0.05) the total mean growth rate of cashmere fibres and, as a result, their length. Cashmere daily growth ratevalues varied significantly (P<0.05) throughout the experiment, while the effect of the physiological status was notedonly in November – December. Furthermore, this parameter also seems to be influenced by climatic factors and, in particular,environmental temperature, as shown by the negative correlation (r = - 0.28; P<0.05) between cashmere dailygrowth rate and environmental temperature. Guard hair length and growth rate did not differ between the two groups,however, they were influenced by time. Cashmere yield and cashmere production were lower in group B (P<0.05). Nodifferences between groups were observed for cashmere diameter. Overall, pregnancy and the consequent period of lactationnegatively influenced cashmere rather than guard hair fibres. These negative effects were noted in quantitativeterms as yield and production dropped by 37% and 43%, respectively. We hypothesise that the complete overlap of pregnancyand lactation with the period of cashmere growth reduced the number of secondary active follicles and their degreeof activity and caused an increase in competition for the partitioning of nutrients between hair follicles and the graviduterus, first, and then the mammary gland, later
El estornino pinto en Argentina: desafíos y prioridades
El día 11 de septiembre de 2015 se desarrolló la mesa redonda “Invasión del estornino pinto (Sturnus vulgaris) en Argentina”, en el marco de la XVI Reunión Argentina de Ornitología organizada por la Sección Ornitología del Museo de La Plata (Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata). En esa oportunidad se informó acerca de las características de la especie, de las consecuencias de su introducción en distintos países, del estado actual de la invasión en Argentina y de los antecedentes relacionados con su control. Además, se realizó una actividad en la que los participantes propusieron medidas de acción prioritarias para el manejo de la especie a nivel local, regional y nacional. En esta contribución resumimos los aspectos más relevantes de la reunión y las conclusiones de la misma
The influence of pregnancy and the beginning of lactation on pelage traits in cashmere goats
The aim of this study was to investigate the effect of pregnancy followed by the beginning of lactation on fibre traits in
cashmere goats. Two groups of cashmere-bearing goats aged between 2-3 years were used. The control group (A) included
12 non-lactating, non-pregnant subjects. The experimental group (B) included 12 goats mated during the first week
of June, in order to have pregnancy and the beginning of lactation coincide with the period when cashmere normally
grows. As expected, Liveweight significantly varied in Group B during the last two months of pregnancy, when foetal
growth reaches its maximum, and following delivery. Hair patch weight, because of the continuous growth of primary and
secondary fibres, increased significantly during the trial (P<0.001). The physiological status considered negatively affected
(P<0.05) the total mean growth rate of cashmere fibres and, as a result, their length. Cashmere daily growth rate
values varied significantly (P<0.05) throughout the experiment, while the effect of the physiological status was noted
only in November – December. Furthermore, this parameter also seems to be influenced by climatic factors and, in particular,
environmental temperature, as shown by the negative correlation (r = - 0.28; P<0.05) between cashmere daily
growth rate and environmental temperature. Guard hair length and growth rate did not differ between the two groups,
however, they were influenced by time. Cashmere yield and cashmere production were lower in group B (P<0.05). No
differences between groups were observed for cashmere diameter. Overall, pregnancy and the consequent period of lactation
negatively influenced cashmere rather than guard hair fibres. These negative effects were noted in quantitative
terms as yield and production dropped by 37% and 43%, respectively. We hypothesise that the complete overlap of pregnancy
and lactation with the period of cashmere growth reduced the number of secondary active follicles and their degree
of activity and caused an increase in competition for the partitioning of nutrients between hair follicles and the gravid
uterus, first, and then the mammary gland, later
Chemical and fatty acid characteristics of meat of Podolian bulls slaughtered at different ages
Podolian cattle represents one of the most important native Italian breed. This breed was once
dolian
reared in many different Italian regions, whereas in recent years a dramatic reduction of the number
of head has relegated this breed to some marginal areas of southern Italy. For meat production, calves
are dam-reared on pasture for about 8-10 months and, subsequently they are fed a finishing diet in
loose house conditions with external paddock. They usually are slaughtered from 14 to 18 months of
age. The aim of this study was to evaluate the chemical and the fatty acid composition of sample cuts
of Podolian bulls slaughtered at different ages; even if breed, age and sex related to differences in the
fatty acid composition of beef cattle have been widely demonstrated (Einchhorn et al., 1986; Huerta-
Leidenz et al., 1996; Malau-Aduli et al., 2000), few data are available on Podolian cattle. This trial was
carried out on 12 Podolian steers, from the same farm in the Basilicata region. The subjects, at the
age of about 10 months, were moved to a stall for fattening and divided into 2 homogeneous groups of
6 animals each. During the trial period, the animal were fed ad libitum with hard wheat straw and a
complete pellet feed, containing barley, oats, field beans, and a vitamin-mineral integrator. The steers
were slaughtered at the age of 14 months (A group) and 18 months (B group), according to veterinary
police rules. The chemical composition of raw Longissimus lumborum (Ll) of the B group presented a
more higher incidence of protein (22.25% vs. 21.34%; P<0.01) and a lower value of moisture (72.29% vs.
73.92%; P<0.01), data also found in the works of Cifuni et al. (2004) and Marino et al. (2006). No sig-
nificant differences emerged in fat percentage between the two ages. The fatty acid composition of the
fat extracted from the raw Ll was not very different into the two groups. The only significant difference
was showed in the ω6/ω3 ratio, the older animals presented a higher value (7.472 vs. 5.270; P<0.05),
due to the higher percentage of ω6 (2.48% vs. 2.25%) and the lower percentage of ω3 (0.35% vs. 0.47%),
into their fat (Carnovale and Nicoli, 2000; Lengyel et al., 2003). The same results were found in the tri-
als carried out by Enser et al. (1999), Elmore et al. (2004) and Descalzo et al. (2005), where the increase
of percentage of ω6 and of the value ω6/ω3 are due to the cereal-based diet used to feed animals. The
group B showed no increase in the percentage of intramuscular fat during the fattening period from
14 to 18 month and to maintain the fatty acid composition very similar to the group A