Development and age estimation of the pouch young of the black-striped wallaby Macropus dorsalis, with notes on reproduction.

2002 ◽  
Vol 24 (2) ◽  
pp. 193
Author(s):  
PM Johnson ◽  
S Delean
Keyword(s):  
Polynomial Growth ◽  
Age Determination ◽  
Mixed Effects Models ◽  
Embryonic Diapause ◽  
Linear Mixed Effects Models ◽  
Linear Mixed Effects ◽  
Growth Equations ◽  
The Relationship ◽  
Age Prediction

Macropus dorsalis was capable of breeding throughout the year. The period of gestation was 33 - 36 days. Birth was usually followed by an oestrus and mating, and a subsequent lactation-controlled embryonic diapause. The period between loss of pouch-young and birth was 29 - 30 days. Pouch life was 192 - 225 days and weaning occurred 81 - 159 days after permanent pouch emergence. Sexual maturity, defined as age at first fertility, occurred at 11.3 months in females and 15.7 months in males. Linear mixed-effects models were used to describe polynomial growth equations for age determination of pouch young using both head and pes length. The relationship between error in age prediction and each body measurement was also defined. Head measurements provided the most accurate estimates of the age of pouch young.

Reproduction of the purple-necked rock-wallaby, Petrogale purpureicollis Le Souef (Marsupialia : Macropodidae) in captivity, with age estimation and development of the pouch young

2002 ◽  
Vol 29 (5) ◽  
pp. 463 ◽  
Author(s):  
Peter M. Johnson ◽  
Steven Delean
Keyword(s):  
Polynomial Growth ◽  
Age Determination ◽  
Mixed Effects Models ◽  
Embryonic Diapause ◽  
Linear Mixed Effects ◽  
In Captivity ◽  
Growth Equations ◽  
The Relationship ◽  
Age Prediction

Reproduction of the purple-necked rock-wallaby, Petrogale purpureicollis, was studied in captivity. The length of the oestrous cycle was 36–38 days followed by a gestation period of 33–35 days. Birth was usually followed by an oestrus and mating, and a subsequent lactation-controlled embryonic diapause. The interval between loss of pouch young and birth was 30–36 days. Pouch life was 178–197 days and weaning occurred 92–171 days after permanent emergence from the pouch. The youngest age at which sexual maturity was reached was 21.8 months for males and 18 months for females. Linear mixed-effects models were used to describe polynomial growth equations for age determination of pouch young using both head and pes length. The relationship between error in age prediction and each body measurement was also defined. Head measurements provided the most accurate estimates of the age of pouch young.

Corrigendum to: Reproduction in the northern bettong, Bettongia tropica Wakefield (Marsupialia : Potoroidae), in captivity, with age estimation and development of the pouch young

2001 ◽  
Vol 28 (6) ◽  
pp. 647 ◽  
Author(s):  
Peter M. Johnson ◽  
Steven Delean
Keyword(s):  
Polynomial Growth ◽  
Mating Behaviour ◽  
Age Determination ◽  
Embryonic Diapause ◽  
Linear Mixed Effects ◽  
In Captivity ◽  
Growth Equations ◽  
The Relationship ◽  
Age Prediction

Reproduction in the northern bettong, Bettongia tropica, was studied in captivity. B. tropica is capable of breeding throughout the year, and mating behaviour is similar to that reported for other Bettongia species. The length of the oestrous cycle was 21–23 days, and the period of gestation was 20–23 days. Birth was usually followed by an oestrus and mating, and a subsequent lactation-controlled embryonic diapause. The interval between loss of pouch young and birth was 19–20 days. Permanent emergence from the pouch occurred at 102–112 days, and young at foot were weaned at 166–185 days of age. Linear mixed-effects models were used to describe polynomial growth equations for age determination of pouch young using both head and pes length. The relationship between error in age prediction and each body measurement was also defined. Pes measurements provided the most accurate estimates of the age of pouch young.

Reproduction in the Proserpine rock-wallaby, Petrogale persephone Maynes (Marsupialia : Macropodidae), in captivity, with age estimation and development of pouch young

1999 ◽  
Vol 26 (5) ◽  
pp. 631 ◽  
Author(s):  
Peter M. Johnson ◽  
J. Steven C. Delean
Keyword(s):  
Polynomial Growth ◽  
Age Determination ◽  
Embryonic Diapause ◽  
Linear Mixed Effects ◽  
In Captivity ◽  
Growth Equations ◽  
The Mean ◽  
The Relationship ◽  
Age Prediction

Reproduction in the Proserpine rock-wallaby, Petrogale persephone, was studied in captivity. Sexual maturity, defined as age at first fertility, was attained at 20.5 months in females whereas males were not mature until 24.8 months. P. persephone is capable of breeding throughout the year. The length of the oestrous cycle was 33–38 days, while the period of gestation was 30–34 days. Birth was usually followed by an oestrus and mating, and a subsequent lactation-controlled embryonic diapause. The mean interval between loss of a pouch young and birth was 31.5 days. Pouch life was 203–215 days and young at foot were weaned 105–139 days after permanent emergence from the pouch. Linear mixed-effects models were used to describe polynomial growth equations for age determination of pouch young using both head and pes length. The relationship between error in age prediction and each body measurement was defined. Head measurements provided the most accurate estimates of the age of pouch young.

Reproduction in the northern bettong, Bettongia tropica Wakefield (Marsupialia: Potoroidae), in captivity, with age estimation and development of pouch young

2001 ◽  
Vol 28 (1) ◽  
pp. 79 ◽  
Author(s):  
Peter M. Johnson ◽  
Steven Delean
Keyword(s):  
Polynomial Growth ◽  
Mating Behaviour ◽  
Age Determination ◽  
Embryonic Diapause ◽  
Linear Mixed Effects ◽  
In Captivity ◽  
Growth Equations ◽  
The Relationship ◽  
Age Prediction

Reproduction in the northern bettong, Bettongia tropica, was studied in captivity. B. tropica is capable of breeding throughout the year, and mating behaviour is similar to that reported for other Bettongia species. The length of the oestrous cycle was 21–23 days, and the period of gestation was 20–23 days. Birth was usually followed by an oestrus and mating, and a subsequent lactation-controlled embryonic diapause. The interval between loss of pouch young and birth was 19–20 days. Permanent emergence from the pouch occurred at 102–112 days, and young at foot were weaned at 166–185 days of age. Linear mixed-effects models were used to describe polynomial growth equations for age determination of pouch young using both head and pes length. The relationship between error in age prediction and each body measurement was also defined. Pes measurements provided the most accurate estimates of the age of pouch young.

Reproduction of Lumholtz's tree-kangaroo, Dendrolagus lumholtzi (Marsupialia : Macropodidae) in captivity, with age estimation and development of the pouch young

2003 ◽  
Vol 30 (5) ◽  
pp. 505 ◽  
Author(s):  
Peter M. Johnson ◽  
Steven Delean
Keyword(s):  
Polynomial Growth ◽  
Post Partum ◽  
Age Determination ◽  
Linear Mixed Effects ◽  
In Captivity ◽  
Growth Equations ◽  
The Relationship ◽  
Dendrolagus Lumholtzi ◽  
Age Prediction

Reproduction in Lumholtz's tree kangaroo, Dendrolagus lumholtzi, was studied in captivity. The length of the oestrous cycle was 47–64 days and the gestation period was 42–48 days. Post partum oestrus and embryonic diapause were not observed in this study. The interval between loss of a pouch young and a return mating was 22 days. Pouch life was 246–275 days long and weaning occurred 87–240 days later. Sexual maturity was obtained in females as early as 2.04 years and in males at 4.6 years. Linear mixed-effects models are used to describe polynomial growth equations for age determination of pouch young using both head and pes length. The relationship between error in age prediction and each body measurement is also defined. Head and pes measurements provide equally accurate estimates of the age of pouch young.

scholarly journals Association of body condition with lameness in dairy cattle: a single-farm longitudinal study

2021 ◽  
pp. 1-4
Author(s):  
Michaela Kranepuhl ◽  
Detlef May ◽  
Edna Hillmann ◽  
Lorenz Gygax
Keyword(s):  
Body Condition ◽  
Body Condition Score ◽  
Mixed Effects ◽  
Mixed Effects Models ◽  
Linear Mixed Effects Models ◽  
Linear Mixed Effects ◽  
Confounding Variables ◽  
Condition Score ◽  
The Impact ◽  
The Relationship

Abstract This research communication describes the relationship between the occurrence of lameness and body condition score (BCS) in a sample of 288 cows from a single farm that were repeatedly scored in the course of 9 months while controlling for confounding variables. The relationship between BCS and lameness was evaluated using generalised linear mixed-effects models. It was found that the proportion of lame cows was higher with decreasing but also with increasing BCS, increased with lactation number and decreased with time since the last claw trimming. This is likely to reflect the importance of sufficient body condition in the prevention of lameness but also raises the question of the impact of overcondition on lameness and the influence of claw trimming events on the assessment of lameness. A stronger focus on BCS might allow improved management of lameness that is still one of the major problems in housed cows.

The Use of Theory of Linear Mixed-Effects Models to Detect Fraudulent Erasures at an Aggregate Level

2021 ◽  
pp. 001316442199489
Author(s):  
Luyao Peng ◽  
Sandip Sinharay
Keyword(s):  
Type I Error ◽  
Real Data ◽  
Mixed Effects ◽  
Error Rates ◽  
Mixed Effects Models ◽  
Type I ◽  
Aggregate Level ◽  
Linear Mixed Effects Models ◽  
Linear Mixed Effects ◽  
Best Linear Unbiased

Wollack et al. (2015) suggested the erasure detection index (EDI) for detecting fraudulent erasures for individual examinees. Wollack and Eckerly (2017) and Sinharay (2018) extended the index of Wollack et al. (2015) to suggest three EDIs for detecting fraudulent erasures at the aggregate or group level. This article follows up on the research of Wollack and Eckerly (2017) and Sinharay (2018) and suggests a new aggregate-level EDI by incorporating the empirical best linear unbiased predictor from the literature of linear mixed-effects models (e.g., McCulloch et al., 2008). A simulation study shows that the new EDI has larger power than the indices of Wollack and Eckerly (2017) and Sinharay (2018). In addition, the new index has satisfactory Type I error rates. A real data example is also included.

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