Observations   on  the  Breeding  Season  in Sheep and its Artificial Extension

John Hammond

doi:10.1017/s0369852100000063

Observations on the Breeding Season in Sheep and its Artificial Extension

Proceedings of the British Society of Animal Production ◽

10.1017/s0369852100000063 ◽

1944 ◽

Vol 1944 (02) ◽

pp. 55-57 ◽

Cited By ~ 1

Author(s):

John Hammond

Keyword(s):

Breeding Season ◽

Grassland Management

Observations on the normal season were made over several years with a small flock of Suffolk X Border Leicester-Cheviot ewes backcrossed with Suffolk rams. The flock was under grassland management ; rams were kept in the whole year round, the fertile ram being usually replaced in the breeding season by a sterile ochred ram. The lambs were left with the ewes until they had ceased to suck. Two ewes have lambed at a time corresponding to service at the end of July or beginning of August ; but the normal season, on the average, extended from mid-September to mid-March, the extremes being the end of August to early April. Ewes suckling lambs born later than July showed slight delay in onset of the breeding season. After lambing in November the interval to the next heat may be as little as three weeks. If ewes are put to the ram at the beginning of the season, so as to lamb down in early February, about half will come on heat again before the end of the season.

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Low reproductive success of the endangered Iberá Seedeater in its only known breeding site, the Iberá Wetlands, Argentina

The Condor ◽

10.1093/ornithapp/duab008 ◽

2021 ◽

Author(s):

Melanie Browne ◽

Sheela P Turbek ◽

Constanza Pasian ◽

Adrián S Di Giacomo

Keyword(s):

Breeding Season ◽

Migratory Birds ◽

Nest Survival ◽

Breeding Site ◽

Grassland Management ◽

Nest Site Selection ◽

Breeding Biology ◽

Cumulative Probability ◽

Conservation Area ◽

Northeastern Argentina

Abstract Subtropical grasslands are highly susceptible to habitat conversion and number among South America’s most threatened ecosystems. The grasslands of northeastern Argentina have been identified as a priority conservation area for threatened capuchino seedeaters because they constitute the main breeding area of these migratory birds. The Iberá Seedeater (Sporophila iberaensis) is a newly described species in the Iberá Wetlands in Argentina whose biology is still poorly understood. The endangered species inhabits grasslands but has only been reported to breed in the Iberá Wetlands ecoregion of northeastern Argentina. To explore the species’ association with grassland vegetation, we studied the breeding biology (clutch size, hatching success, and fledgling production) of the Iberá Seedeater and the main parameters that influence nest survival and nest-site selection. We conducted nest searches and banded adults and nestlings in Iberá National Park during the breeding seasons of 2016–2018. The breeding season of the Iberá Seedeater was highly synchronous and the cumulative probability of nest survival was 0.16. The daily nest survival rate decreased as the breeding season advanced, survival was lower for nests supported by Rhynchospora corymbosa than Paspalum durifolium, the two main nest substrates, and the main causes of nest failure were nest predation and strong winds. Additionally, the population exhibited male-biased site fidelity and a low female return rate. In contrast to other capuchinos, whose breeding biology is associated with upland grasslands, the Iberá Seedeater nested exclusively in flooded lowland grasslands on marsh plants. Thus, effective lowland grassland management is key to maintain the vegetation structure required for reproduction in the Iberá Seedeater.

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Effect of Melatonin Implantation to Sperm Donor Rams on Post-thaw Viability and Acrosomal Integrity of Sperm Cells in the Breeding and Non-breeding Season

Reproduction in Domestic Animals ◽

10.1046/j.1439-0531.2001.d01-40.x ◽

2001 ◽

Vol 36 (3-4) ◽

pp. 211-215 ◽

Cited By ~ 19

Author(s):

A Kaya ◽

M Aksoy ◽

N Baspınar ◽

C Yıldız ◽

MB Ataman

Keyword(s):

Breeding Season ◽

Sperm Cells ◽

Sperm Donor ◽

Acrosomal Integrity

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Observation on the breeding biology of Polypedates teraiensis (Dubois, 1987) (Amphibia: Rhacophoridae)

Science Vision ◽

10.33493/scivis.17.01.05 ◽

2017 ◽

Vol 17 (1) ◽

pp. 25-32

Author(s):

Jacinta Lalchhanhimi ◽

Lalremsanga H.T.

Keyword(s):

Sexual Dimorphism ◽

Breeding Season ◽

Sound Production ◽

Reproductive Function ◽

Breeding Biology ◽

Tree Frog ◽

University Campus ◽

Morphometric Measurements ◽

Advertisement Calls ◽

Males And Females

The breeding biology of tree frog, Polypedates teraiensis was studied during the breeding season at Mizoram University Campus. It was found that sound production by male during the breeding season was primarily a reproductive function and advertisement calls attract females to the breeding areas and announce other males that a given territory is occupied. The aim of this study was to provide the detailed information on the breeding behaviour and the advertisement calls of Polypedates teraiensis. The morphometric measurements of the amplecting pairs (males and females) for sexual dimorphism along with clutch sizes were also studied.

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DIFFERENT OESTRUS INDUCTION METHODS IN AWASSI EWES DURING THE OUT OF BREEDING SEASON

Basrah Journal of veterinary Research ◽

10.33762/bvetr.2014.98795 ◽

2014 ◽

Vol 13 (2) ◽

pp. 66-74

Author(s):

Jawad .K .Taher

Keyword(s):

Breeding Season ◽

Oestrus Induction

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Plant diversity and species richness of Ljubljana marsh grasslands under the influence of different cutting and fertilizing regimes

Acta Agronomica Hungarica ◽

10.1556/aagr.57.2009.2.11 ◽

2009 ◽

Vol 57 (2) ◽

pp. 197-203 ◽

Cited By ~ 2

Author(s):

T. Sinkovč

Keyword(s):

Species Richness ◽

Plant Diversity ◽

Grassland Management ◽

Botanical Composition ◽

Significant Negative Effect ◽

Negative Effect ◽

Cutting Regimes ◽

N Rates ◽

Exploitation Intensity ◽

Plot Design

The botanical composition of grasslands determines the agronomic and natural values of swards. Good grassland management usually improves herbage value, but on the other hand it frequently decreases the plant diversity and species richness in the swards. In 1999 a field trial in a split-plot design with four replicates was therefore established on the Arrhenatherion type of vegetation in Ljubljana marsh meadows in order to investigate this relationship. Cutting regimes (2 cuts — with normal and delayed first cut, 3 cuts and 4 cuts per year) were allocated to the main plots and fertiliser treatments (zero fertiliser — control, PK and NPK with 2 or 3 N rates) were allocated to the sub-plots. The results at the 1 st cutting in the 5 th trial year were as follows: Fertilising either with PK or NPK had no significant negative effect on plant diversity in any of the cutting regimes. In most treatments the plant number even increased slightly compared to the control. On average, 20 species were listed on both unfertilised and fertilised swards. At this low to moderate level of exploitation intensity, the increased number of cuts had no significant negative effect on plant diversity either (19 species at 2 cuts vs. 20 species at 3 or 4 cuts). PK fertilisation increased the proportion of legumes in the herbage in the case of 2 or 3 cuts. The proportion of grasses in the herbage increased in all the fertilisation treatments with an increased numbers of cuts. Fertiliser treatment considerably reduced the proportion of marsh horsetail ( Equisetum palustre ) in the herbage of the meadows. This effect was even more pronounced at higher cut numbers. The proportion of Equisetum palustre in the herbage was the highest in the unfertilised sward with 2 cuts (26.4 %) and the lowest in the NPK-fertilised sward with 4 cuts (1.4%).

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